Voltage variation on generator

[nrhareiner]

Good day everyone,

This may or may not be an actual problem, but something I have just noticed. We have been dry camping for many days. Obviously we are running generator for charging batteries, AC etc.

I know that the voltage will vary as the load varies per leg. However, I am noticing that one leg can get to 106 while other leg at 134. First leg using 22 amps power and second 10 amps.

Generator is 17.5KW Powertech.

Just want to make sure that there is no serious problem developing from voltage regulator or stator.

Thank you

[Jon Wehrenberg]

I would have a generator guy check it Kim. Some variation due to loading can be expected, but in both legs you are at or just past allowable limits of 120V +/- 10% which is industry standard.

[nrhareiner]

Jon,

I agree, with no load they read 121, 124 left and right. With loads the difference increases to the point I mentioned earlier. Powertech (make of generator) is only 50 miles from home. I plan to have them check on the status.

thanks,

[nrhareiner]

Hello Jim,

I have Trace inverters, and yes the bus feeds the generators through the inverters. However, everything is fine and normal when plugged in to shore power. The only problem is one generator power. The shore power is feed through the same manner as the generator.

[Kevin Erion]

Jim, I don't think you statement about our generators is true. If it is 220, it will have 2 legs that can produce different voltage. There is a voltage regulator that I think can be adjusted for both sides of the 120, but I could be wrong.

[Jon Wehrenberg]

Jim,

Your issues were on both shore and generator, and Kim's is only on generator.

[dreamchasers]

Concerning the voltage variance on the Powertech generator, I have documentation that mentions this issue. On page 22 of the attached link, Voltage Connections, last paragraph. My generator voltage will also show unbalanced at times. My research of the issue guided to the operators manual and the description of the issue. It seems that this is the normal operation mode of the Powertech.

I see this as "the way it is" for coaches that use both lines of the 120 volts (240 from the generator). Click on the link below for the operator manual for the 17.5 Powertech.

http://www.dreamchasers.us/pog/PTSMH - 15-17.5-20 OPERATORS MANUAL.pdf (http://www.dreamchasers.us/pog/PTSMH%20-%2015-17.5-20%20OPERATORS%20MANUAL.pdf)

Hope this helps.

Hector

[nrhareiner]

Good morning Hector,

I have the manual, and in the past have seen variations on the voltage one side compared to the other. However, over the past couple of days I am seeing much larger variations, and the side with low voltage never gets to the float level on the charger side. I am plugged into shore power now and everything returned to normal. I think something is wrong on the voltage regulator.

[truk4u]

Kim,

This has been a common occurence for me also, both my present Liberty and previous CC. I talked to Powertec and they claim it's normal.

[Jon Wehrenberg]

That sounds a lot like BS.

Both my coach generators had perhaps a 5 volt spread between legs depending on loading, but Kim is describing a 30 degree spread. Phrased another way Powertech is saying everyone else can regulate the voltage on both legs to within a few degrees, but their product can have a spread of 30 degrees and that is OK. They need to bring that stuff they are spreading up here to Knoxville to put on my tomato garden.

[Kevin Erion]

I agree with Jon!

[Coloradobus]

Power Tech seems to have a recollection problem. I called them about our 15KW generator and gave them our serial number, 15PTSKW97250. The guy in Leesburg Fla, said they didn't make it. I said it has Power Tech stamped all over it and the Beaver itemization list in the coach states it a PTS 15KW, listing 97250 as serial #.. Power Tech says its not theirs and I need more numbers in the serial number, so no wonder they don't know what range their generators operate at.:confused:

[nrhareiner]

I spoke to Powertech yesterday. After I described the problem they said that certainly is not normal. I did question whether I had one of there generators. When I again told them the conversion name and year of the bus they confirmed it was their's. Since they are only 55 miles from home I will visit them in the near future. I will post back after that visit hopefully with an easy resolution.

[JIM CHALOUPKA]

Kim, are you any further along on a resolution to your situation?

JIM

[charlie]

would like any info. any one has on power tec gen that runs about 1or 2 minutes then stops in a 2000 cc h345 gen con controler. rebuilt by factor. did not help' charlie.

[sawdust_128]

Somehow in all my travels, I failed to conect with this thread. I have seen similar results to what Kim was describing and resolved it by reseting 2 of the inverter programming parameters.

1. The 17.5K power tech (installed in most Vantare's) is a 60 AMP generator. The default value for this parameter for most brands of inverters in 50 AMP.

2. On the Xantrex inverters, if I have my shore power set to 30 amp and not plugged in and running the generator, the metering gets very erratic.

Why it works this way, well, it's that ignorance and apapthy thing. Igf I see this kind of response from the meters, I check this parameters. I have a 100% incidence of correcting the issue with those actions.

Good luck.

[gmcbuffalo]

I had this two minute problem with a PT17.5 and it turned out to be sucking air in to the fuel line. I diagnosis this by opening the bypass stopcock in the fuel line, which is up high close to the front of the motor, while the engine was running. With this open it didn't stop on me. I then checked all the connections and fuel filter seal, tighten all and things hae been fine since.
GregM

[Pete]

If you have auto-start on your genset, make sure it is in the off position.
I started mine a couple of times not realizing it was on and the genset shuts down thinking the batteries are charged up.
Just a thought.