dry camping
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12-02-2007, 13:58
Post: #11
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dry camping
The primary drain (through the inverters) is the power to the
refrigerator. It will limit your ability to operate off the grid with an all-electric coach. (My '95 is all electric.) Newer refrigerators are perhaps a bit more economical to operate than the 22 cu ft 2-door Amana that I have in my coach -- but you're likely to experience the similar power drain. For example, I have 6 model 4D AGM-type house batteries. These have about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, that's an overstatement of what's available, as you can't deplete the battery more than 50% for standard wet cell or by more than 60% for AGM batteries. So that would mean there's between 660 and 792 amp hours available from the battery to power all the 120 volt systems that are serviced by the inverters. (I have two, 2500 watt inverters.) Also, don't forget that the inverters cause a loss (10% or more) while changing the 12 vdc to 120 vac. Don't forget that amps X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at 120 v per hour. Convert that to 12 vdc, and its about 83 amps. With the inverter loss, that's about 95 or 100 amps (per hour while the refrigerator is running)... so that suggests about 6 to 8 hours or perhaps 10 hours of operation (since it doesn't run 100% of the time) just for the refrigerator. Add the microwave (high draw, but short period) plus the various lights and the 12 volt stuff... and then you can see that the batteries are kind of limiting! Here's where you have to do some math. First figure out the approximate hourly draw in amps of each appliance that runs on 120 volts. Don't forget that _some_ of the lights run on 120 volts and are powered by the inverters. Of course, all 12 volt items and appliances also draw from the batteries. So, you also have to figure out what 12 volt appliances you have operating. Do not ignore the draw from the Microphor toilet compressor nor from the air-system auxiliary compressor, if you have one (I don't) along with various signal lights, etc. etc. -- well, to be honest, there's a _lot_ of load on a 'bird and without a source to recharge, the batteries can be drawn down to a dangerous level in just a few days, even when everything is "off." So, back to the refrigerator -- the practical situation is to make sure your house batteries are fully charged. If you have an isolation switch to "turn off" everything, it would help. Anyway, when you think your batteries are fully charged, isolate them (and unplug shore power), then check the voltage. (This is the "resting" voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts (wet cell batteries are different). Then, turn on the isolation switch (apply the normal load) -- wait and hour, remove the load, and check the voltage. 12.4 volts is 50% depletion and 12.25 volts is 60% depletion -- do not let the volts drop below 12.25 volts!!! ---this is "resting" voltage measured from the battery terminals. Measurements drawn from other locations (e.g. a fuse panel) are likely to be much lower due to line losses.) My experience has been that "boondocking" isn't especially practical. I can shut down the generator in the evening, but I usually need to restart after about 12 hours or so. So, if I shut down at 8:00 PM, I'll usually need to start the generator by about 8:00 AM the next morning to avoid causing any damage to my batteries. This has caused a fair amount of heart burn when I've stayed in a CA state park that had a generator operation ban between 8 PM and 10 AM ... those two hours were nail biting time and I had to shut down any/all items that made demands on the batteries. My plan (the next time I boondock) is to pull the breakers on the inverters perhaps at 10 PM or so, and see how the batteries are the next morning. The refrigerator won't warm up much during the night, if it is not opened and if we're in a reasonably cool location. I've compared notes with another all-electric Blue Bird owner (just this past weekend at the Lone Star Birds rally in Kerrville, TX) and I'm of the impression that my voltage drain seems to be on the high side (so I may need to further explore possible reasons). The reality is that you can probably turn off the generator in the evening then turn it back on in the morning without major problems. You can run the generator for 3 hours or so to bring the batteries back up to full or near full charge. Then you can shut down the generator for a few hours, then run it for 3 or 4 hours until the time you wish complete quiet at night (or until any required shut down time occurs). The coach can be off the grid without the generator for periods of several hours -- but it will need to have power to recover the batteries rather more often and/or for longer periods than coaches that have LP gas appliances. See Poop Sheets by Phred at: <http://www.phrannie.org/phredex.html> #5 has a thorough discussion of "electrical stuff." Pete Masterson '95 Blue Bird Wanderlodge WBDA 42 aeonix1@... On the road at Lubbock Texas following a great weekend with the Lone Star Birds at Kerrville, TX. On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > Just purchased a 2005 LXi and need some advice on dry camping. I cook > in bbq contests and sometimes no power or 110 only. Dealer says I > will > have to use the generator all the time. Although the unit is all > electric, will not use the stove top or microwave while camping. > It is > hard to believe I can't dry camp any length of time and then use > generator to keep batteries up. > Is the dealers advice right or does anyone have thoughts or > suggestions? > > Jerry Smith > 2005 450 LXI |
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12-02-2007, 14:10
Post: #12
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dry camping
You may have to check the batteries with a multi-tester at the
battery terminals. I have a non-standard Heart Link 2000 R controller installed in my coach that has a digital readout of the battery voltage at all times. (Only problem is that it's misleading as it measures the batteries under load which is a lower reading than when they're not under load. Pete Masterson '95 Blue Bird Wanderlodge WBDA 42 aeonix1@... On the road at Lubbock Texas On Dec 1, 2007, at 4:22 PM, JERRY SMITH wrote: > Thanks for the reply have gone through the manual and the box. Can > find > nothing on the auto start for the generator and see no digital read > out in > the coach as to condition of the batteries. Bought coach at > Parliament. > Previous plastic coaches I had all had digital read out on > condition of > batteries. > Jerry Smith > > -------Original Message------- > > From: WanderlodgeForum@yahoogroups.com > Date: 12/01/07 16:50:51 > To: WanderlodgeForum@yahoogroups.com > Subject: [WanderlodgeForum] Re: dry camping > > Jerry, |
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12-02-2007, 14:59
Post: #13
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dry camping
Pete have you ever considered L16s. Randy has four in his rig and swears by
them. He says with a little modification he could put six in the available space. They sure pack a lot of amps. On 02/12/2007, Pete Masterson > > The primary drain (through the inverters) is the power to the > refrigerator. It will limit your ability to operate off the grid with > an all-electric coach. (My '95 is all electric.) Newer refrigerators > are perhaps a bit more economical to operate than the 22 cu ft 2-door > Amana that I have in my coach -- but you're likely to experience the > similar power drain. > > For example, I have 6 model 4D AGM-type house batteries. These have > about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, > that's an overstatement of what's available, as you can't deplete the > battery more than 50% for standard wet cell or by more than 60% for > AGM batteries. So that would mean there's between 660 and 792 amp > hours available from the battery to power all the 120 volt systems > that are serviced by the inverters. (I have two, 2500 watt > inverters.) Also, don't forget that the inverters cause a loss (10% > or more) while changing the 12 vdc to 120 vac. Don't forget that amps > X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at > 120 v per hour. Convert that to 12 vdc, and its about 83 amps. With > the inverter loss, that's about 95 or 100 amps (per hour while the > refrigerator is running)... so that suggests about 6 to 8 hours or > perhaps 10 hours of operation (since it doesn't run 100% of the time) > just for the refrigerator. Add the microwave (high draw, but short > period) plus the various lights and the 12 volt stuff... and then you > can see that the batteries are kind of limiting! > > Here's where you have to do some math. First figure out the > approximate hourly draw in amps of each appliance that runs on 120 > volts. Don't forget that _some_ of the lights run on 120 volts and > are powered by the inverters. Of course, all 12 volt items and > appliances also draw from the batteries. So, you also have to figure > out what 12 volt appliances you have operating. Do not ignore the > draw from the Microphor toilet compressor nor from the air-system > auxiliary compressor, if you have one (I don't) along with various > signal lights, etc. etc. -- well, to be honest, there's a _lot_ of > load on a 'bird and without a source to recharge, the batteries can > be drawn down to a dangerous level in just a few days, even when > everything is "off." > > So, back to the refrigerator -- the practical situation is to make > sure your house batteries are fully charged. If you have an isolation > switch to "turn off" everything, it would help. Anyway, when you > think your batteries are fully charged, isolate them (and unplug > shore power), then check the voltage. (This is the "resting" > voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts > (wet cell batteries are different). Then, turn on the isolation > switch (apply the normal load) -- wait and hour, remove the load, and > check the voltage. 12.4 volts is 50% depletion and 12.25 volts is 60% > depletion -- do not let the volts drop below 12.25 volts!!! ---this > is "resting" voltage measured from the battery terminals. > Measurements drawn from other locations (e.g. a fuse panel) are > likely to be much lower due to line losses.) > > My experience has been that "boondocking" isn't especially practical. > I can shut down the generator in the evening, but I usually need to > restart after about 12 hours or so. So, if I shut down at 8:00 PM, > I'll usually need to start the generator by about 8:00 AM the next > morning to avoid causing any damage to my batteries. This has caused > a fair amount of heart burn when I've stayed in a CA state park that > had a generator operation ban between 8 PM and 10 AM ... those two > hours were nail biting time and I had to shut down any/all items that > made demands on the batteries. > > My plan (the next time I boondock) is to pull the breakers on the > inverters perhaps at 10 PM or so, and see how the batteries are the > next morning. The refrigerator won't warm up much during the night, > if it is not opened and if we're in a reasonably cool location. > > I've compared notes with another all-electric Blue Bird owner (just > this past weekend at the Lone Star Birds rally in Kerrville, TX) and > I'm of the impression that my voltage drain seems to be on the high > side (so I may need to further explore possible reasons). > > The reality is that you can probably turn off the generator in the > evening then turn it back on in the morning without major problems. > You can run the generator for 3 hours or so to bring the batteries > back up to full or near full charge. Then you can shut down the > generator for a few hours, then run it for 3 or 4 hours until the > time you wish complete quiet at night (or until any required shut > down time occurs). > > The coach can be off the grid without the generator for periods of > several hours -- but it will need to have power to recover the > batteries rather more often and/or for longer periods than coaches > that have LP gas appliances. > > See Poop Sheets by Phred at: > <http://www.phrannie.org/phredex.html> > #5 has a thorough discussion of "electrical stuff." > > Pete Masterson > '95 Blue Bird Wanderlodge WBDA 42 > aeonix1@... > On the road at Lubbock Texas following a great weekend with the Lone > Star Birds at Kerrville, TX. > > On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > > > Just purchased a 2005 LXi and need some advice on dry camping. I cook > > in bbq contests and sometimes no power or 110 only. Dealer says I > > will > > have to use the generator all the time. Although the unit is all > > electric, will not use the stove top or microwave while camping. > > It is > > hard to believe I can't dry camp any length of time and then use > > generator to keep batteries up. > > Is the dealers advice right or does anyone have thoughts or > > suggestions? > > > > Jerry Smith > > 2005 450 LXI > > > -- Rob, Sue & Merlin Robinson 94 WLWB [Non-text portions of this message have been removed] |
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12-02-2007, 17:43
Post: #14
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dry camping
Not true. My Amana home fridge can run all day on inverters. I
charge in the evening and it runs all night with no problem. Tom 2 Shoes McCarthy Poway CA --- In WanderlodgeForum@yahoogroups.com, "Gary Smith" wrote: > > Jerry, > Dealer is right on for the most part. Your 120v refrigerator gobbles 30-40 > amps of 12v power (via the inverter) each hour, so even a 4-6 hour period > will draw down your house batteries something serious, and that's with > everything else turned off, if you can. > Gary > SOB > ----- Original Message ----- > From: "medpro28" <medpro@...> > To: > Sent: Saturday, December 01, 2007 3:08 PM > Subject: [WanderlodgeForum] dry camping > > > Just purchased a 2005 LXi and need some advice on dry camping. I cook > in bbq contests and sometimes no power or 110 only. Dealer says I will > have to use the generator all the time. Although the unit is all > electric, will not use the stove top or microwave while camping. It is > hard to believe I can't dry camp any length of time and then use > generator to keep batteries up. > Is the dealers advice right or does anyone have thoughts or suggestions? > > Jerry Smith > 2005 450 LXI > |
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12-03-2007, 01:55
Post: #15
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dry camping
Unfortunately, I just replaced the 4Ds this spring. The previous set
were (apparently) damaged by an improper controller setting that occurred while the coach was in various dealer's hands. (It was reset to the default settings, so it thought it was charging wet cell batteries -- which over charged the AGMs.) I'll check into the L16s... I did look at some various alternatives, but I wasn't able to find anything that would (1) fit (2) provide at least as much AH capacity as the 4Ds. (i.e. "better" batteries wouldn't fit to allow enough to match/improve on the 4Ds.) Thanks. Pete Masterson '95 Blue Bird Wanderlodge WBDA 42 aeonix1@... On the road at Lubbock TX where it's 26 degrees this morning. On Dec 2, 2007, at 8:59 PM, Rob Robinson wrote: > Pete have you ever considered L16s. Randy has four in his rig and > swears by > them. He says with a little modification he could put six in the > available > space. They sure pack a lot of amps. > > On 02/12/2007, Pete Masterson >> >> The primary drain (through the inverters) is the power to the >> refrigerator. It will limit your ability to operate off the grid with >> an all-electric coach. (My '95 is all electric.) Newer refrigerators >> are perhaps a bit more economical to operate than the 22 cu ft 2-door >> Amana that I have in my coach -- but you're likely to experience the >> similar power drain. >> >> For example, I have 6 model 4D AGM-type house batteries. These have >> about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, >> that's an overstatement of what's available, as you can't deplete the >> battery more than 50% for standard wet cell or by more than 60% for >> AGM batteries. So that would mean there's between 660 and 792 amp >> hours available from the battery to power all the 120 volt systems >> that are serviced by the inverters. (I have two, 2500 watt >> inverters.) Also, don't forget that the inverters cause a loss (10% >> or more) while changing the 12 vdc to 120 vac. Don't forget that amps >> X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at >> 120 v per hour. Convert that to 12 vdc, and its about 83 amps. With >> the inverter loss, that's about 95 or 100 amps (per hour while the >> refrigerator is running)... so that suggests about 6 to 8 hours or >> perhaps 10 hours of operation (since it doesn't run 100% of the time) >> just for the refrigerator. Add the microwave (high draw, but short >> period) plus the various lights and the 12 volt stuff... and then you >> can see that the batteries are kind of limiting! >> >> Here's where you have to do some math. First figure out the >> approximate hourly draw in amps of each appliance that runs on 120 >> volts. Don't forget that _some_ of the lights run on 120 volts and >> are powered by the inverters. Of course, all 12 volt items and >> appliances also draw from the batteries. So, you also have to figure >> out what 12 volt appliances you have operating. Do not ignore the >> draw from the Microphor toilet compressor nor from the air-system >> auxiliary compressor, if you have one (I don't) along with various >> signal lights, etc. etc. -- well, to be honest, there's a _lot_ of >> load on a 'bird and without a source to recharge, the batteries can >> be drawn down to a dangerous level in just a few days, even when >> everything is "off." >> >> So, back to the refrigerator -- the practical situation is to make >> sure your house batteries are fully charged. If you have an isolation >> switch to "turn off" everything, it would help. Anyway, when you >> think your batteries are fully charged, isolate them (and unplug >> shore power), then check the voltage. (This is the "resting" >> voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts >> (wet cell batteries are different). Then, turn on the isolation >> switch (apply the normal load) -- wait and hour, remove the load, and >> check the voltage. 12.4 volts is 50% depletion and 12.25 volts is 60% >> depletion -- do not let the volts drop below 12.25 volts!!! ---this >> is "resting" voltage measured from the battery terminals. >> Measurements drawn from other locations (e.g. a fuse panel) are >> likely to be much lower due to line losses.) >> >> My experience has been that "boondocking" isn't especially practical. >> I can shut down the generator in the evening, but I usually need to >> restart after about 12 hours or so. So, if I shut down at 8:00 PM, >> I'll usually need to start the generator by about 8:00 AM the next >> morning to avoid causing any damage to my batteries. This has caused >> a fair amount of heart burn when I've stayed in a CA state park that >> had a generator operation ban between 8 PM and 10 AM ... those two >> hours were nail biting time and I had to shut down any/all items that >> made demands on the batteries. >> >> My plan (the next time I boondock) is to pull the breakers on the >> inverters perhaps at 10 PM or so, and see how the batteries are the >> next morning. The refrigerator won't warm up much during the night, >> if it is not opened and if we're in a reasonably cool location. >> >> I've compared notes with another all-electric Blue Bird owner (just >> this past weekend at the Lone Star Birds rally in Kerrville, TX) and >> I'm of the impression that my voltage drain seems to be on the high >> side (so I may need to further explore possible reasons). >> >> The reality is that you can probably turn off the generator in the >> evening then turn it back on in the morning without major problems. >> You can run the generator for 3 hours or so to bring the batteries >> back up to full or near full charge. Then you can shut down the >> generator for a few hours, then run it for 3 or 4 hours until the >> time you wish complete quiet at night (or until any required shut >> down time occurs). >> >> The coach can be off the grid without the generator for periods of >> several hours -- but it will need to have power to recover the >> batteries rather more often and/or for longer periods than coaches >> that have LP gas appliances. >> >> See Poop Sheets by Phred at: >> <http://www.phrannie.org/phredex.html> >> #5 has a thorough discussion of "electrical stuff." >> >> Pete Masterson >> '95 Blue Bird Wanderlodge WBDA 42 >> aeonix1@... >> On the road at Lubbock Texas following a great weekend with the Lone >> Star Birds at Kerrville, TX. >> >> On Dec 1, 2007, at 2:08 PM, medpro28 wrote: >> >>> Just purchased a 2005 LXi and need some advice on dry camping. I >>> cook >>> in bbq contests and sometimes no power or 110 only. Dealer says I >>> will >>> have to use the generator all the time. Although the unit is all >>> electric, will not use the stove top or microwave while camping. >>> It is >>> hard to believe I can't dry camp any length of time and then use >>> generator to keep batteries up. >>> Is the dealers advice right or does anyone have thoughts or >>> suggestions? >>> >>> Jerry Smith >>> 2005 450 LXI >> >> >> > > > > -- > Rob, Sue & Merlin Robinson > 94 WLWB > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > |
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12-03-2007, 01:58
Post: #16
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dry camping
Pete, great explanation. A big help to a guy like me that is electrically
challenged. Thank you for the help. Jerry Smith 2005 450 LXi Sarasota, Fl. -------Original Message------- From: WanderlodgeForum@yahoogroups.com Date: 12/02/07 20:59:42 To: WanderlodgeForum@yahoogroups.com Subject: Re: [WanderlodgeForum] dry camping The primary drain (through the inverters) is the power to the refrigerator. It will limit your ability to operate off the grid with an all-electric coach. (My '95 is all electric.) Newer refrigerators are perhaps a bit more economical to operate than the 22 cu ft 2-door Amana that I have in my coach -- but you're likely to experience the similar power drain. For example, I have 6 model 4D AGM-type house batteries. These have about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, that's an overstatement of what's available, as you can't deplete the battery more than 50% for standard wet cell or by more than 60% for AGM batteries. So that would mean there's between 660 and 792 amp hours available from the battery to power all the 120 volt systems that are serviced by the inverters. (I have two, 2500 watt inverters.) Also, don't forget that the inverters cause a loss (10% or more) while changing the 12 vdc to 120 vac. Don't forget that amps X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at 120 v per hour. Convert that to 12 vdc, and its about 83 amps. With the inverter loss, that's about 95 or 100 amps (per hour while the refrigerator is running)... so that suggests about 6 to 8 hours or perhaps 10 hours of operation (since it doesn't run 100% of the time) just for the refrigerator. Add the microwave (high draw, but short period) plus the various lights and the 12 volt stuff... and then you can see that the batteries are kind of limiting! Here's where you have to do some math. First figure out the approximate hourly draw in amps of each appliance that runs on 120 volts. Don't forget that _some_ of the lights run on 120 volts and are powered by the inverters. Of course, all 12 volt items and appliances also draw from the batteries. So, you also have to figure out what 12 volt appliances you have operating. Do not ignore the draw from the Microphor toilet compressor nor from the air-system auxiliary compressor, if you have one (I don't) along with various signal lights, etc. etc. -- well, to be honest, there's a _lot_ of load on a 'bird and without a source to recharge, the batteries can be drawn down to a dangerous level in just a few days, even when everything is "off." So, back to the refrigerator -- the practical situation is to make sure your house batteries are fully charged. If you have an isolation switch to "turn off" everything, it would help. Anyway, when you think your batteries are fully charged, isolate them (and unplug shore power), then check the voltage. (This is the "resting" voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts (wet cell batteries are different). Then, turn on the isolation switch (apply the normal load) -- wait and hour, remove the load, and check the voltage. 12.4 volts is 50% depletion and 12.25 volts is 60% depletion -- do not let the volts drop below 12.25 volts!!! ---this is "resting" voltage measured from the battery terminals. Measurements drawn from other locations (e.g. a fuse panel) are likely to be much lower due to line losses.) My experience has been that "boondocking" isn't especially practical. I can shut down the generator in the evening, but I usually need to restart after about 12 hours or so. So, if I shut down at 8:00 PM, I'll usually need to start the generator by about 8:00 AM the next morning to avoid causing any damage to my batteries. This has caused a fair amount of heart burn when I've stayed in a CA state park that had a generator operation ban between 8 PM and 10 AM ... those two hours were nail biting time and I had to shut down any/all items that made demands on the batteries. My plan (the next time I boondock) is to pull the breakers on the inverters perhaps at 10 PM or so, and see how the batteries are the next morning. The refrigerator won't warm up much during the night, if it is not opened and if we're in a reasonably cool location. I've compared notes with another all-electric Blue Bird owner (just this past weekend at the Lone Star Birds rally in Kerrville, TX) and I'm of the impression that my voltage drain seems to be on the high side (so I may need to further explore possible reasons). The reality is that you can probably turn off the generator in the evening then turn it back on in the morning without major problems. You can run the generator for 3 hours or so to bring the batteries back up to full or near full charge. Then you can shut down the generator for a few hours, then run it for 3 or 4 hours until the time you wish complete quiet at night (or until any required shut down time occurs). The coach can be off the grid without the generator for periods of several hours -- but it will need to have power to recover the batteries rather more often and/or for longer periods than coaches that have LP gas appliances. See Poop Sheets by Phred at: <http://www.phrannie.org/phredex.html> #5 has a thorough discussion of "electrical stuff." Pete Masterson '95 Blue Bird Wanderlodge WBDA 42 aeonix1@... On the road at Lubbock Texas following a great weekend with the Lone Star Birds at Kerrville, TX. On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > Just purchased a 2005 LXi and need some advice on dry camping. I cook > in bbq contests and sometimes no power or 110 only. Dealer says I > will > have to use the generator all the time. Although the unit is all > electric, will not use the stove top or microwave while camping. > It is > hard to believe I can't dry camp any length of time and then use > generator to keep batteries up. > Is the dealers advice right or does anyone have thoughts or > suggestions? > > Jerry Smith > 2005 450 LXI [Non-text portions of this message have been removed] |
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12-03-2007, 04:25
Post: #17
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dry camping
Great explanation of the amp hour figure, Pete. Your refrigerator
shouldn't use that much juice though. If you can keep the door shut most of the time, it should run about 30% of the time. The duty cycle goes up a lot if you're fanning the door. Also, the defrost heater uses a lot of juice when it cycles. It will normally occur once or twice a day and last for about 12 or 15 minutes. Then the refrigeration system has to run longer to cool things back off. You can improve things a lot with a domestic refrigerator by keeping the condenser coils clean and keeping the doors shut as much as possible. Also, if there is a switch on its control panel for "humidity control" or some such, you might want to keep it in the off or normal or whatever it's labeled position. This is for some electrical heating elements that are in the mullions around the door openings to keep them from sweating in high humidity areas. The humidity probably doesn't get that high inside your coach anyway. They use a fair amount of electricity 24/7 when turned on. Not a big issue on shore power, but could be significant when dry camping. A lot of the newer refrigerators solve the sweating issue by routing the hot gas piping from the compressor through the mullions before going to the condenser; that's why you'll notice the mullions feeling hot to the touch. I'd like to see what the actual running amp draw is on one of these. I work on appliances for a living; maybe I can remember to put an Amprobe on one and see. I have a digital data logger that I can leave in a refrigerator for a couple of days and tell you exactly how long it's running and when it defrosts. Guess I need to find out how much current it's drawing. Never been an issue in a home, but would be good to know for when running on batteries. Travis, the Newell guy in Lubbock, Texas On Dec 2, 2007, at 7:58 PM, Pete Masterson wrote: > The primary drain (through the inverters) is the power to the > refrigerator. It will limit your ability to operate off the grid with > an all-electric coach. (My '95 is all electric.) Newer refrigerators > are perhaps a bit more economical to operate than the 22 cu ft 2-door > Amana that I have in my coach -- but you're likely to experience the > similar power drain. > > For example, I have 6 model 4D AGM-type house batteries. These have > about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, > that's an overstatement of what's available, as you can't deplete the > battery more than 50% for standard wet cell or by more than 60% for > AGM batteries. So that would mean there's between 660 and 792 amp > hours available from the battery to power all the 120 volt systems > that are serviced by the inverters. (I have two, 2500 watt > inverters.) Also, don't forget that the inverters cause a loss (10% > or more) while changing the 12 vdc to 120 vac. Don't forget that amps > X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at > 120 v per hour. Convert that to 12 vdc, and its about 83 amps. With > the inverter loss, that's about 95 or 100 amps (per hour while the > refrigerator is running)... so that suggests about 6 to 8 hours or > perhaps 10 hours of operation (since it doesn't run 100% of the time) > just for the refrigerator. Add the microwave (high draw, but short > period) plus the various lights and the 12 volt stuff... and then you > can see that the batteries are kind of limiting! > > Here's where you have to do some math. First figure out the > approximate hourly draw in amps of each appliance that runs on 120 > volts. Don't forget that _some_ of the lights run on 120 volts and > are powered by the inverters. Of course, all 12 volt items and > appliances also draw from the batteries. So, you also have to figure > out what 12 volt appliances you have operating. Do not ignore the > draw from the Microphor toilet compressor nor from the air-system > auxiliary compressor, if you have one (I don't) along with various > signal lights, etc. etc. -- well, to be honest, there's a _lot_ of > load on a 'bird and without a source to recharge, the batteries can > be drawn down to a dangerous level in just a few days, even when > everything is "off." > > So, back to the refrigerator -- the practical situation is to make > sure your house batteries are fully charged. If you have an isolation > switch to "turn off" everything, it would help. Anyway, when you > think your batteries are fully charged, isolate them (and unplug > shore power), then check the voltage. (This is the "resting" > voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts > (wet cell batteries are different). Then, turn on the isolation > switch (apply the normal load) -- wait and hour, remove the load, and > check the voltage. 12.4 volts is 50% depletion and 12.25 volts is 60% > depletion -- do not let the volts drop below 12.25 volts!!! ---this > is "resting" voltage measured from the battery terminals. > Measurements drawn from other locations (e.g. a fuse panel) are > likely to be much lower due to line losses.) > > My experience has been that "boondocking" isn't especially practical. > I can shut down the generator in the evening, but I usually need to > restart after about 12 hours or so. So, if I shut down at 8:00 PM, > I'll usually need to start the generator by about 8:00 AM the next > morning to avoid causing any damage to my batteries. This has caused > a fair amount of heart burn when I've stayed in a CA state park that > had a generator operation ban between 8 PM and 10 AM ... those two > hours were nail biting time and I had to shut down any/all items that > made demands on the batteries. > > My plan (the next time I boondock) is to pull the breakers on the > inverters perhaps at 10 PM or so, and see how the batteries are the > next morning. The refrigerator won't warm up much during the night, > if it is not opened and if we're in a reasonably cool location. > > I've compared notes with another all-electric Blue Bird owner (just > this past weekend at the Lone Star Birds rally in Kerrville, TX) and > I'm of the impression that my voltage drain seems to be on the high > side (so I may need to further explore possible reasons). > > The reality is that you can probably turn off the generator in the > evening then turn it back on in the morning without major problems. > You can run the generator for 3 hours or so to bring the batteries > back up to full or near full charge. Then you can shut down the > generator for a few hours, then run it for 3 or 4 hours until the > time you wish complete quiet at night (or until any required shut > down time occurs). > > The coach can be off the grid without the generator for periods of > several hours -- but it will need to have power to recover the > batteries rather more often and/or for longer periods than coaches > that have LP gas appliances. > > See Poop Sheets by Phred at: > <http://www.phrannie.org/phredex.html> > #5 has a thorough discussion of "electrical stuff." > > Pete Masterson > '95 Blue Bird Wanderlodge WBDA 42 > aeonix1@... > On the road at Lubbock Texas following a great weekend with the Lone > Star Birds at Kerrville, TX. > > On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > > > Just purchased a 2005 LXi and need some advice on dry camping. I > cook > > in bbq contests and sometimes no power or 110 only. Dealer says I > > will > > have to use the generator all the time. Although the unit is all > > electric, will not use the stove top or microwave while camping. > > It is > > hard to believe I can't dry camp any length of time and then use > > generator to keep batteries up. > > Is the dealers advice right or does anyone have thoughts or > > suggestions? > > > > Jerry Smith > > 2005 450 LXI > > > [Non-text portions of this message have been removed] |
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12-03-2007, 07:56
Post: #18
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dry camping
I had no idea that there even was an RV of any type that did not have
propane tanks? Guess that shows how out of touch I am. How about heat in cold conditions? I guess you would certainly be running the generator then? I guess you pays your money and takes your choice. Gasoline or propane. Makes not a lot of difference? John Heckman central Pa 1973 FC > > Great explanation of the amp hour figure, Pete. Your refrigerator > shouldn't use that much juice though. If you can keep the door shut > most of the time, it should run about 30% of the time. The duty cycle > goes up a lot if you're fanning the door. Also, the defrost heater > uses a lot of juice when it cycles. It will normally occur once or > twice a day and last for about 12 or 15 minutes. Then the > refrigeration system has to run longer to cool things back off. You > can improve things a lot with a domestic refrigerator by keeping the > condenser coils clean and keeping the doors shut as much as possible. > Also, if there is a switch on its control panel for "humidity > control" or some such, you might want to keep it in the off or normal > or whatever it's labeled position. This is for some electrical > heating elements that are in the mullions around the door openings to > keep them from sweating in high humidity areas. The humidity probably > doesn't get that high inside your coach anyway. They use a fair > amount of electricity 24/7 when turned on. Not a big issue on shore > power, but could be significant when dry camping. A lot of the newer > refrigerators solve the sweating issue by routing the hot gas piping > from the compressor through the mullions before going to the > condenser; that's why you'll notice the mullions feeling hot to the > touch. > > I'd like to see what the actual running amp draw is on one of these. > I work on appliances for a living; maybe I can remember to put an > Amprobe on one and see. I have a digital data logger that I can leave > in a refrigerator for a couple of days and tell you exactly how long > it's running and when it defrosts. Guess I need to find out how much > current it's drawing. Never been an issue in a home, but would be > good to know for when running on batteries. > > Travis, the Newell guy in Lubbock, Texas > > > On Dec 2, 2007, at 7:58 PM, Pete Masterson wrote: > > > The primary drain (through the inverters) is the power to the > > refrigerator. It will limit your ability to operate off the grid with > > an all-electric coach. (My '95 is all electric.) Newer refrigerators > > are perhaps a bit more economical to operate than the 22 cu ft 2- door > > Amana that I have in my coach -- but you're likely to experience the > > similar power drain. > > > > For example, I have 6 model 4D AGM-type house batteries. These have > > about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, > > that's an overstatement of what's available, as you can't deplete the > > battery more than 50% for standard wet cell or by more than 60% for > > AGM batteries. So that would mean there's between 660 and 792 amp > > hours available from the battery to power all the 120 volt systems > > that are serviced by the inverters. (I have two, 2500 watt > > inverters.) Also, don't forget that the inverters cause a loss (10% > > or more) while changing the 12 vdc to 120 vac. Don't forget that amps > > X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at > > 120 v per hour. Convert that to 12 vdc, and its about 83 amps. With > > the inverter loss, that's about 95 or 100 amps (per hour while the > > refrigerator is running)... so that suggests about 6 to 8 hours or > > perhaps 10 hours of operation (since it doesn't run 100% of the time) > > just for the refrigerator. Add the microwave (high draw, but short > > period) plus the various lights and the 12 volt stuff... and then you > > can see that the batteries are kind of limiting! > > > > Here's where you have to do some math. First figure out the > > approximate hourly draw in amps of each appliance that runs on 120 > > volts. Don't forget that _some_ of the lights run on 120 volts and > > are powered by the inverters. Of course, all 12 volt items and > > appliances also draw from the batteries. So, you also have to figure > > out what 12 volt appliances you have operating. Do not ignore the > > draw from the Microphor toilet compressor nor from the air-system > > auxiliary compressor, if you have one (I don't) along with various > > signal lights, etc. etc. -- well, to be honest, there's a _lot_ of > > load on a 'bird and without a source to recharge, the batteries can > > be drawn down to a dangerous level in just a few days, even when > > everything is "off." > > > > So, back to the refrigerator -- the practical situation is to make > > sure your house batteries are fully charged. If you have an isolation > > switch to "turn off" everything, it would help. Anyway, when you > > think your batteries are fully charged, isolate them (and unplug > > shore power), then check the voltage. (This is the "resting" > > voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts > > (wet cell batteries are different). Then, turn on the isolation > > switch (apply the normal load) -- wait and hour, remove the load, and > > check the voltage. 12.4 volts is 50% depletion and 12.25 volts is 60% > > depletion -- do not let the volts drop below 12.25 volts!!! --- this > > is "resting" voltage measured from the battery terminals. > > Measurements drawn from other locations (e.g. a fuse panel) are > > likely to be much lower due to line losses.) > > > > My experience has been that "boondocking" isn't especially practical. > > I can shut down the generator in the evening, but I usually need to > > restart after about 12 hours or so. So, if I shut down at 8:00 PM, > > I'll usually need to start the generator by about 8:00 AM the next > > morning to avoid causing any damage to my batteries. This has caused > > a fair amount of heart burn when I've stayed in a CA state park that > > had a generator operation ban between 8 PM and 10 AM ... those two > > hours were nail biting time and I had to shut down any/all items that > > made demands on the batteries. > > > > My plan (the next time I boondock) is to pull the breakers on the > > inverters perhaps at 10 PM or so, and see how the batteries are the > > next morning. The refrigerator won't warm up much during the night, > > if it is not opened and if we're in a reasonably cool location. > > > > I've compared notes with another all-electric Blue Bird owner (just > > this past weekend at the Lone Star Birds rally in Kerrville, TX) and > > I'm of the impression that my voltage drain seems to be on the high > > side (so I may need to further explore possible reasons). > > > > The reality is that you can probably turn off the generator in the > > evening then turn it back on in the morning without major problems. > > You can run the generator for 3 hours or so to bring the batteries > > back up to full or near full charge. Then you can shut down the > > generator for a few hours, then run it for 3 or 4 hours until the > > time you wish complete quiet at night (or until any required shut > > down time occurs). > > > > The coach can be off the grid without the generator for periods of > > several hours -- but it will need to have power to recover the > > batteries rather more often and/or for longer periods than coaches > > that have LP gas appliances. > > > > See Poop Sheets by Phred at: > > <http://www.phrannie.org/phredex.html> > > #5 has a thorough discussion of "electrical stuff." > > > > Pete Masterson > > '95 Blue Bird Wanderlodge WBDA 42 > > aeonix1@... > > On the road at Lubbock Texas following a great weekend with the Lone > > Star Birds at Kerrville, TX. > > > > On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > > > > > Just purchased a 2005 LXi and need some advice on dry camping. I > > cook > > > in bbq contests and sometimes no power or 110 only. Dealer says I > > > will > > > have to use the generator all the time. Although the unit is all > > > electric, will not use the stove top or microwave while camping. > > > It is > > > hard to believe I can't dry camp any length of time and then use > > > generator to keep batteries up. > > > Is the dealers advice right or does anyone have thoughts or > > > suggestions? > > > > > > Jerry Smith > > > 2005 450 LXI > > > > > > > > > > [Non-text portions of this message have been removed] > |
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12-03-2007, 10:00
Post: #19
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dry camping
John, in my case I have not filled the propane tank in three years. It
operates the cook top, reefer, and outside grill. It is still half full. Up until recently, we used the coach quite often. Heat comes from Wabasto, (hot). We (5 of us) can dry camp without significant problems operating the genset about 4 hours per day if we are conservative. Otherwise, the genset runs longer. --- In WanderlodgeForum@yahoogroups.com, "bubblerboy64" > > I had no idea that there even was an RV of any type that did not have > propane tanks? Guess that shows how out of touch I am. How about > heat in cold conditions? I guess you would certainly be running the > generator then? I guess you pays your money and takes your choice. > Gasoline or propane. Makes not a lot of difference? > John Heckman > central Pa > 1973 FC > > > Great explanation of the amp hour figure, Pete. Your refrigerator > > shouldn't use that much juice though. If you can keep the door > shut > > most of the time, it should run about 30% of the time. The duty > cycle > > goes up a lot if you're fanning the door. Also, the defrost heater > > uses a lot of juice when it cycles. It will normally occur once or > > twice a day and last for about 12 or 15 minutes. Then the > > refrigeration system has to run longer to cool things back off. > You > > can improve things a lot with a domestic refrigerator by keeping > the > > condenser coils clean and keeping the doors shut as much as > possible. > > Also, if there is a switch on its control panel for "humidity > > control" or some such, you might want to keep it in the off or > normal > > or whatever it's labeled position. This is for some electrical > > heating elements that are in the mullions around the door openings > to > > keep them from sweating in high humidity areas. The humidity > probably > > doesn't get that high inside your coach anyway. They use a fair > > amount of electricity 24/7 when turned on. Not a big issue on > shore > > power, but could be significant when dry camping. A lot of the > newer > > refrigerators solve the sweating issue by routing the hot gas > piping > > from the compressor through the mullions before going to the > > condenser; that's why you'll notice the mullions feeling hot to > the > > touch. > > > > I'd like to see what the actual running amp draw is on one of > these. > > I work on appliances for a living; maybe I can remember to put an > > Amprobe on one and see. I have a digital data logger that I can > leave > > in a refrigerator for a couple of days and tell you exactly how > long > > it's running and when it defrosts. Guess I need to find out how > much > > current it's drawing. Never been an issue in a home, but would be > > good to know for when running on batteries. > > > > Travis, the Newell guy in Lubbock, Texas > > > > > > On Dec 2, 2007, at 7:58 PM, Pete Masterson wrote: > > > > > The primary drain (through the inverters) is the power to the > > > refrigerator. It will limit your ability to operate off the grid > with > > > an all-electric coach. (My '95 is all electric.) Newer > refrigerators > > > are perhaps a bit more economical to operate than the 22 cu ft 2- > door > > > Amana that I have in my coach -- but you're likely to experience > the > > > similar power drain. > > > > > > For example, I have 6 model 4D AGM-type house batteries. These > have > > > about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, > > > that's an overstatement of what's available, as you can't deplete > the > > > battery more than 50% for standard wet cell or by more than 60% > for > > > AGM batteries. So that would mean there's between 660 and 792 amp > > > hours available from the battery to power all the 120 volt systems > > > that are serviced by the inverters. (I have two, 2500 watt > > > inverters.) Also, don't forget that the inverters cause a loss > (10% > > > or more) while changing the 12 vdc to 120 vac. Don't forget that > amps > > > X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at > > > 120 v per hour. Convert that to 12 vdc, and its about 83 amps. > With > > > the inverter loss, that's about 95 or 100 amps (per hour while the > > > refrigerator is running)... so that suggests about 6 to 8 hours or > > > perhaps 10 hours of operation (since it doesn't run 100% of the > time) > > > just for the refrigerator. Add the microwave (high draw, but short > > > period) plus the various lights and the 12 volt stuff... and then > you > > > can see that the batteries are kind of limiting! > > > > > > Here's where you have to do some math. First figure out the > > > approximate hourly draw in amps of each appliance that runs on 120 > > > volts. Don't forget that _some_ of the lights run on 120 volts and > > > are powered by the inverters. Of course, all 12 volt items and > > > appliances also draw from the batteries. So, you also have to > figure > > > out what 12 volt appliances you have operating. Do not ignore the > > > draw from the Microphor toilet compressor nor from the air-system > > > auxiliary compressor, if you have one (I don't) along with various > > > signal lights, etc. etc. -- well, to be honest, there's a _lot_ of > > > load on a 'bird and without a source to recharge, the batteries > can > > > be drawn down to a dangerous level in just a few days, even when > > > everything is "off." > > > > > > So, back to the refrigerator -- the practical situation is to make > > > sure your house batteries are fully charged. If you have an > isolation > > > switch to "turn off" everything, it would help. Anyway, when you > > > think your batteries are fully charged, isolate them (and unplug > > > shore power), then check the voltage. (This is the "resting" > > > voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts > > > (wet cell batteries are different). Then, turn on the isolation > > > switch (apply the normal load) -- wait and hour, remove the load, > and > > > check the voltage. 12.4 volts is 50% depletion and 12.25 volts is > 60% > > > depletion -- do not let the volts drop below 12.25 volts!!! --- > this > > > is "resting" voltage measured from the battery terminals. > > > Measurements drawn from other locations (e.g. a fuse panel) are > > > likely to be much lower due to line losses.) > > > > > > My experience has been that "boondocking" isn't especially > practical. > > > I can shut down the generator in the evening, but I usually need > to > > > restart after about 12 hours or so. So, if I shut down at 8:00 PM, > > > I'll usually need to start the generator by about 8:00 AM the next > > > morning to avoid causing any damage to my batteries. This has > caused > > > a fair amount of heart burn when I've stayed in a CA state park > that > > > had a generator operation ban between 8 PM and 10 AM ... those two > > > hours were nail biting time and I had to shut down any/all items > that > > > made demands on the batteries. > > > > > > My plan (the next time I boondock) is to pull the breakers on the > > > inverters perhaps at 10 PM or so, and see how the batteries are > the > > > next morning. The refrigerator won't warm up much during the > night, > > > if it is not opened and if we're in a reasonably cool location. > > > > > > I've compared notes with another all-electric Blue Bird owner > (just > > > this past weekend at the Lone Star Birds rally in Kerrville, TX) > and > > > I'm of the impression that my voltage drain seems to be on the > high > > > side (so I may need to further explore possible reasons). > > > > > > The reality is that you can probably turn off the generator in the > > > evening then turn it back on in the morning without major > problems. > > > You can run the generator for 3 hours or so to bring the batteries > > > back up to full or near full charge. Then you can shut down the > > > generator for a few hours, then run it for 3 or 4 hours until the > > > time you wish complete quiet at night (or until any required shut > > > down time occurs). > > > > > > The coach can be off the grid without the generator for periods of > > > several hours -- but it will need to have power to recover the > > > batteries rather more often and/or for longer periods than coaches > > > that have LP gas appliances. > > > > > > See Poop Sheets by Phred at: > > > <http://www.phrannie.org/phredex.html> > > > #5 has a thorough discussion of "electrical stuff." > > > > > > Pete Masterson > > > '95 Blue Bird Wanderlodge WBDA 42 > > > aeonix1@ > > > On the road at Lubbock Texas following a great weekend with the > Lone > > > Star Birds at Kerrville, TX. > > > > > > On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > > > > > > > Just purchased a 2005 LXi and need some advice on dry camping. > I > > > cook > > > > in bbq contests and sometimes no power or 110 only. Dealer says > I > > > > will > > > > have to use the generator all the time. Although the unit is all > > > > electric, will not use the stove top or microwave while camping. > > > > It is > > > > hard to believe I can't dry camp any length of time and then use > > > > generator to keep batteries up. > > > > Is the dealers advice right or does anyone have thoughts or > > > > suggestions? > > > > > > > > Jerry Smith > > > > 2005 450 LXI > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > |
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12-03-2007, 11:12
Post: #20
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dry camping
Leroy what coach and year do you have?
On 03/12/2007, Leroy A. Eckert > > John, in my case I have not filled the propane tank in three years. It > operates the cook top, reefer, and outside grill. It is still half > full. Up until recently, we used the coach quite often. Heat comes > from Wabasto, (hot). We (5 of us) can dry camp without significant > problems operating the genset about 4 hours per day if we are > conservative. Otherwise, the genset runs longer. > > --- In WanderlodgeForum@yahoogroups.com > "bubblerboy64" > > > > I had no idea that there even was an RV of any type that did not have > > propane tanks? Guess that shows how out of touch I am. How about > > heat in cold conditions? I guess you would certainly be running the > > generator then? I guess you pays your money and takes your choice. > > Gasoline or propane. Makes not a lot of difference? > > John Heckman > > central Pa > > 1973 FC > > > > > Great explanation of the amp hour figure, Pete. Your refrigerator > > > shouldn't use that much juice though. If you can keep the door > > shut > > > most of the time, it should run about 30% of the time. The duty > > cycle > > > goes up a lot if you're fanning the door. Also, the defrost heater > > > uses a lot of juice when it cycles. It will normally occur once or > > > twice a day and last for about 12 or 15 minutes. Then the > > > refrigeration system has to run longer to cool things back off. > > You > > > can improve things a lot with a domestic refrigerator by keeping > > the > > > condenser coils clean and keeping the doors shut as much as > > possible. > > > Also, if there is a switch on its control panel for "humidity > > > control" or some such, you might want to keep it in the off or > > normal > > > or whatever it's labeled position. This is for some electrical > > > heating elements that are in the mullions around the door openings > > to > > > keep them from sweating in high humidity areas. The humidity > > probably > > > doesn't get that high inside your coach anyway. They use a fair > > > amount of electricity 24/7 when turned on. Not a big issue on > > shore > > > power, but could be significant when dry camping. A lot of the > > newer > > > refrigerators solve the sweating issue by routing the hot gas > > piping > > > from the compressor through the mullions before going to the > > > condenser; that's why you'll notice the mullions feeling hot to > > the > > > touch. > > > > > > I'd like to see what the actual running amp draw is on one of > > these. > > > I work on appliances for a living; maybe I can remember to put an > > > Amprobe on one and see. I have a digital data logger that I can > > leave > > > in a refrigerator for a couple of days and tell you exactly how > > long > > > it's running and when it defrosts. Guess I need to find out how > > much > > > current it's drawing. Never been an issue in a home, but would be > > > good to know for when running on batteries. > > > > > > Travis, the Newell guy in Lubbock, Texas > > > > > > > > > On Dec 2, 2007, at 7:58 PM, Pete Masterson wrote: > > > > > > > The primary drain (through the inverters) is the power to the > > > > refrigerator. It will limit your ability to operate off the grid > > with > > > > an all-electric coach. (My '95 is all electric.) Newer > > refrigerators > > > > are perhaps a bit more economical to operate than the 22 cu ft 2- > > door > > > > Amana that I have in my coach -- but you're likely to experience > > the > > > > similar power drain. > > > > > > > > For example, I have 6 model 4D AGM-type house batteries. These > > have > > > > about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However, > > > > that's an overstatement of what's available, as you can't deplete > > the > > > > battery more than 50% for standard wet cell or by more than 60% > > for > > > > AGM batteries. So that would mean there's between 660 and 792 amp > > > > hours available from the battery to power all the 120 volt systems > > > > that are serviced by the inverters. (I have two, 2500 watt > > > > inverters.) Also, don't forget that the inverters cause a loss > > (10% > > > > or more) while changing the 12 vdc to 120 vac. Don't forget that > > amps > > > > X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at > > > > 120 v per hour. Convert that to 12 vdc, and its about 83 amps. > > With > > > > the inverter loss, that's about 95 or 100 amps (per hour while the > > > > refrigerator is running)... so that suggests about 6 to 8 hours or > > > > perhaps 10 hours of operation (since it doesn't run 100% of the > > time) > > > > just for the refrigerator. Add the microwave (high draw, but short > > > > period) plus the various lights and the 12 volt stuff... and then > > you > > > > can see that the batteries are kind of limiting! > > > > > > > > Here's where you have to do some math. First figure out the > > > > approximate hourly draw in amps of each appliance that runs on 120 > > > > volts. Don't forget that _some_ of the lights run on 120 volts and > > > > are powered by the inverters. Of course, all 12 volt items and > > > > appliances also draw from the batteries. So, you also have to > > figure > > > > out what 12 volt appliances you have operating. Do not ignore the > > > > draw from the Microphor toilet compressor nor from the air-system > > > > auxiliary compressor, if you have one (I don't) along with various > > > > signal lights, etc. etc. -- well, to be honest, there's a _lot_ of > > > > load on a 'bird and without a source to recharge, the batteries > > can > > > > be drawn down to a dangerous level in just a few days, even when > > > > everything is "off." > > > > > > > > So, back to the refrigerator -- the practical situation is to make > > > > sure your house batteries are fully charged. If you have an > > isolation > > > > switch to "turn off" everything, it would help. Anyway, when you > > > > think your batteries are fully charged, isolate them (and unplug > > > > shore power), then check the voltage. (This is the "resting" > > > > voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts > > > > (wet cell batteries are different). Then, turn on the isolation > > > > switch (apply the normal load) -- wait and hour, remove the load, > > and > > > > check the voltage. 12.4 volts is 50% depletion and 12.25 volts is > > 60% > > > > depletion -- do not let the volts drop below 12.25 volts!!! --- > > this > > > > is "resting" voltage measured from the battery terminals. > > > > Measurements drawn from other locations (e.g. a fuse panel) are > > > > likely to be much lower due to line losses.) > > > > > > > > My experience has been that "boondocking" isn't especially > > practical. > > > > I can shut down the generator in the evening, but I usually need > > to > > > > restart after about 12 hours or so. So, if I shut down at 8:00 PM, > > > > I'll usually need to start the generator by about 8:00 AM the next > > > > morning to avoid causing any damage to my batteries. This has > > caused > > > > a fair amount of heart burn when I've stayed in a CA state park > > that > > > > had a generator operation ban between 8 PM and 10 AM ... those two > > > > hours were nail biting time and I had to shut down any/all items > > that > > > > made demands on the batteries. > > > > > > > > My plan (the next time I boondock) is to pull the breakers on the > > > > inverters perhaps at 10 PM or so, and see how the batteries are > > the > > > > next morning. The refrigerator won't warm up much during the > > night, > > > > if it is not opened and if we're in a reasonably cool location. > > > > > > > > I've compared notes with another all-electric Blue Bird owner > > (just > > > > this past weekend at the Lone Star Birds rally in Kerrville, TX) > > and > > > > I'm of the impression that my voltage drain seems to be on the > > high > > > > side (so I may need to further explore possible reasons). > > > > > > > > The reality is that you can probably turn off the generator in the > > > > evening then turn it back on in the morning without major > > problems. > > > > You can run the generator for 3 hours or so to bring the batteries > > > > back up to full or near full charge. Then you can shut down the > > > > generator for a few hours, then run it for 3 or 4 hours until the > > > > time you wish complete quiet at night (or until any required shut > > > > down time occurs). > > > > > > > > The coach can be off the grid without the generator for periods of > > > > several hours -- but it will need to have power to recover the > > > > batteries rather more often and/or for longer periods than coaches > > > > that have LP gas appliances. > > > > > > > > See Poop Sheets by Phred at: > > > > <http://www.phrannie.org/phredex.html> > > > > #5 has a thorough discussion of "electrical stuff." > > > > > > > > Pete Masterson > > > > '95 Blue Bird Wanderlodge WBDA 42 > > > > aeonix1@ > > > > On the road at Lubbock Texas following a great weekend with the > > Lone > > > > Star Birds at Kerrville, TX. > > > > > > > > On Dec 1, 2007, at 2:08 PM, medpro28 wrote: > > > > > > > > > Just purchased a 2005 LXi and need some advice on dry camping. > > I > > > > cook > > > > > in bbq contests and sometimes no power or 110 only. Dealer says > > I > > > > > will > > > > > have to use the generator all the time. Although the unit is all > > > > > electric, will not use the stove top or microwave while camping. > > > > > It is > > > > > hard to believe I can't dry camp any length of time and then use > > > > > generator to keep batteries up. > > > > > Is the dealers advice right or does anyone have thoughts or > > > > > suggestions? > > > > > > > > > > Jerry Smith > > > > > 2005 450 LXI > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > -- Rob, Sue & Merlin Robinson 94 WLWB [Non-text portions of this message have been removed] |
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