Voltage variation

[gcyeaw]

I got my second Cruisair working today and ran them both on the gennie for a while to test the results (it was around 90 degrees in the sun). It got the interior to 73 degrees, which is pretty good I think.

The bad thing was I noticed the AC voltage was bouncing up and down around 7 to 10 volts variation. It is a cheap plug in meter, but even if it is not accurate it shouldn't vary that much. It was probably cycling every second. The engine sound was very constant, so I suspect the regulator. Tomorrow I will hook up the frequency meter and see what gives.

I may be taking advantage of the expertise at Tom Warners rally next week to trouble shoot.

[gcyeaw]

Just for fun I put my ocilloscope on the generator to see what it loooks like. Compared to the house AC it has some differences. I noticed just after the + and - peaks, there is a momentary drop-out. This could be the brushes arcing, but I am not sure. Here ia a picture of the house power, and then one of the generator with two AC's running. It really doesn't make a difference with or without the AC's.

Anyone else ever look at the waveform?

[Bill Pape]

Hmmmmmmmmmm.

Now why did you look at that ??, most folks do not have a O-scope.
I think the brushes or commutator need replaced or atleast cleaned. Although I have never look at the 12.5K generator for clean power. Just an opinion.

[Turbokitty]

Pretty cool Gardner!

Do you know how old the regulator is. I know that there has been several upgrades/improvements with regard to regulators.

I would presume that the engine rpm is not surging/varying?

I have found that a "kill-a-watt" meter works great especially since they also tell Hz. For about 30 bucks I keep one plugged into the outlet by the door and check it first when an electrical issue insues

You scope at Toms rally would be cool to see what other generators are putting out for sine form as well as what some of the inverters look like too?


Handy gadget!

[Ed Wimberley]

Gardner

RutRow that looks BAD,there should not be a break in signal.
Possibly you have caught it in time I suspect the slip-rings on brushes.
Looks like brushes losing contact with Slip Rings.
Good luck Hopefully you caught it prior to explosion.

[fxdwg]

How many hours are on your genny?

[Robert Britton]

That is interesting Gardner, I’ve never seen a scope like that…and the fact you got a picture of it and put it on here for us to see…cool stuff!

[gcyeaw]

The first thing I want to do is look at Shanes. My scope is not calibrated (I paid $50, what do you expect), so it is only good for viewing the waveform. I use my meter for volts and frequency.

Wait till you see the output wave from a non-sinsoidal inverter, it is very scary looking.