More replacing on bus

[Pete Masterson]

It's normal for the Hz to move around a bit as power output of the generator changes. Plus or minus 10% wouldn't be alarming. It might affect motors (but usually the motors draw enough power bring the Hz back to within 2 or 3% of 60) and it definitely affects timing circuits. Expect the AC digital clocks to run fast or slow depending on what side of 60 Hz you're running.

In high school, I was a member of the engineering club that had built a scoreboard for the football field -- but it was too far from the grid, so we also ran a generator to power it. (This was in the early 60s.) It's been way too long, so I don't recall what brand generator or its size but it was an old "surplus" model ... it was mounted on a small trailer and had an air-cooled 2 cyl engine. It was a bear to start with a pull-cord (but we were young).

After several games using their traditional stop-clocks to check against the scoreboard, the timekeepers started using the scoreboard clock for the official time (using a wired remote to start/stop the clock). That's when we discovered we could speed up or slow down the clock with the Hz -- when our team was ahead, we'd speed it up and when the team was behind, we'd slow it down. We could operate the clock by plus or minus 5% or so... because of time outs, etc. nobody ever got wise to what we were doing. After two years, they put in lights for night games, and then wired the scoreboard to the grid, and we were out of the time manipulation business...

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42

El Sobrante CA

"aeonix1@mac.com"

On Apr 26, 2009, at 5:34 PM, Curt Sprenger wrote:

Bob,

You are too busy...

Do you know what the HZ reading is on the Gen. powered AC Legs? Our coach has the Power Management System, and the digital display sometimes shows HZ higher than 60 HZ. Under more load the HZ drops to 60.