No Inverter charge with shore but OK with genset

[dentmac]

With the genset off and post plugged in, I have 2 phase 120 V displayed on the gauges above door, Inverters are on with 120V coming through as everything runs and 120 V lights work (Bath rooms and galley table). But the Inverters do not charge. So I have power from post.. but no charge.
With genset... all normal.. chargers work.
What is different between 120 V post supply to Inverters and 120V gen supply to inverters? Post supply gives no charge.

I have reset inverters, cut all power/ shutoffs and rebooted..

Help appreciated

[davidbrady]

Ross,

Have you gotten any insight into this problem? We have complete M450 electrical schematics in our Document Library.

I looked at the power distribution schematics and everything after the first priority transfer switch is common to both systems, genny power or house power.

I keep thinking there's something going on with the energy management system. But that seems odd because you said you have two legs of 120VAC shore power making its way to the house loads. There may be something happening at the shore power, perhaps reverse polarity, or both legs actually being wired to only one in-phase source. Could the energy management system detect this and prune back the battery chargers? I'd check the poll for 2 separate legs of 120VAC. Put a voltmeter across the red and black leads to see if you're getting 240VAC.

[dentmac]

Thanks for the schematics.. Power seems OK to inverters..and OK through the bypass.
Possibly need 115 V input?? Could that cause inverters to not charge??

Meters above door read 110 V not 115 as I posted earlier.
Ross



Latest :
Bypass inverter 2 puts shore power directly EMS panel 3 which then does not shed and works normally.
So allowing power to go through inverter causes the EMS issue.
But still no charge with inverter one. (Last night both inverters charged for a while) Very unlikely that both inverters toasted at the same time.
John .. I think the power input from post is suspect. I'll find/borrow an accurate meter. My new one is crap.

Borrowed a good meter -- 110, 111 on post .. each line and 224 across. Inverter outputs on inverter recept. reads 105 V !
No line V drop when coach attached ( meter with plug part way out).

(01-22-2015 15:36)davidbrady Wrote:  Ross,

Have you gotten any insight into this problem? We have complete M450 electrical schematics in our Document Library.

I looked at the power distribution schematics and everything after the first priority transfer switch is common to both systems, genny power or house power.

I keep thinking there's something going on with the energy management system. But that seems odd because you said you have two legs of 120VAC shore power making its way to the house loads. There may be something happening at the shore power, perhaps reverse polarity, or both legs actually being wired to only one in-phase source. Could the energy management system detect this and prune back the battery chargers? I'd check the poll for 2 separate legs of 120VAC. Put a voltmeter across the red and black leads to see if you're getting 240VAC.

[davidbrady]

105V at the inverter receptacles with shore power plugged in means the inverters are inverting, not charging. 105V is normal because you have modified sine wave inverters. Without a true-rms voltmeter the triangular waveform will be read as 105V rms.

[cmillsap]

I'm not familiar with the M450's Multiplex system but in looking at the schematics, the 120vac power sources (Gen & Shore) through the transfer is typical. So the inverters/chargers don't care which is the power source and should work the same on both power sources.

If the Genset is supplying a strong 120VAC and everything works as it should, I would question the power supplied from the shore post.
I would try another shore power source before I would tear into anything in an effort to "fix" the problem. The bus may not have a problem.

[dentmac]

Thank you everyone,
I have decided not to start tearing things open (Done that too many times).
I agree/believe/hope that is the weak power at the post. I have checked other posts and they have same power. One maintenance gent said there was another coach in the park with some power problems too...another problem causing Canuck.
Tomorrow , we move . I'll post the results.
Thanks,
Ross

The Oaks at Sacred Rocks
Boulevard CA

(01-22-2015 17:14)cmillsap Wrote:  I'm not familiar with the M450's Multiplex system but in looking at the schematics, the 120vac power sources (Gen & Shore) through the transfer is typical. So the inverters/chargers don't care which is the power source and should work the same on both power sources.

If the Genset is supplying a strong 120VAC and everything works as it should, I would question the power supplied from the shore post.
I would try another shore power source before I would tear into anything in an effort to "fix" the problem. The bus may not have a problem.

[dentmac]

Hi,
Everything OK ! At a new resort with reasonable electricity and having NO issues.

My gauges over the door read 115 and 112 (They have always been slightly different but was never concerned about exact reading)
At The Oaks at Sacred Rocks park, they showed 111 and 110. Both lines were lives and ~220 accross. There could have been a frequency issue also.
At ~ 1:00 AM my chargers would start up for a while. No doubt the quality or voltage improved.

So the inverters are very critical about the input power quality. More then the manuals indicate.

Always more to learn... AND buy a GOOD accurate meter. A new Fluke 115 is being shipped NOW.

Thank you for the help,Saved me from starting to rip into things.
Ross