Community Forums

Ghostman · 10-01-2019, 10:46 PM

I have a 2011 Fleetwood Expedition 38B with an Onan 8k generator. Recently I was dry camping and noticed the coach was cool. I realized my AC was not working. I then noticed the generator was running and according to the command center inside the coach it's producing 66 amps but there was no load on it. I then noticed the lights on the surge guard automatic transfer switch was not on indicating it was not getting power. This surge guard is only a few months old as I changed it last spring after I was not getting shore power but was getting generator power.

I checked all the breakers and nothing. I can't locate the junction box to check that. It appears the issue is between the generator and transfer box.

jelag · 10-02-2019, 06:07 AM

There is a main breaker on the generator....

Remember that most Surge protectors are serviceable when the cover is removed... These are nothing more than commercial contacts designed for heavy electrical loads installed in a RV...

One other thought.... almost all high voltage failures in an RV (110-220) side of the electrical system are from loose connectors... vibration is the cause of most of these connectors coming loose... in most cases the torque on the fasteners is 35 in lbs.... of course you never see this problem in a home or commercial application because the fastener is tightened and there is never the vibration...
There is another blog I follow written by a retired electrical engineer who specializes in RV systems... he writes a very interesting news letter...

Remember if there is heat at an electrical connection its either a bad connection or pitted contacts that cause a change in the resistance valve of the connection and heat.... and later a failure will occur....

Take a volt meter, check the electrical connections where your generator power is switched to the RV.... One side is shore power, the other side is generator power... and these contactors... if there is no incoming power go back to the generator and see if the main breaker is tripped..

spdracr39 · 10-02-2019, 06:19 AM

How can you have amps without a load ?

twinboat · 10-02-2019, 06:25 AM

Maybe it was producing 66 volts.

That's not enough to switch over the auto transfer switch.

Where is the surge guard wired in, before or after the auto transfer switch ? If before it, like most, its not a factor in generator power.

Have you had the generator fuel filters serviced lately ? Could be a fuel problem not letting the generator turn up to the proper RPMs.

okcnewbie · 10-02-2019, 06:45 AM

If it was 66VAC here is a possible explanation from the troubleshooting guide at flightsystems.com

per guide;

Q. The voltage at the AC outlet is too low (below 112 VAC at no load) or goes down more than a few volts when a load is added. What causes this?
A. First, make sure that the generator is running at rated speed. This can be done with a multi-meter that has a “fre-quency” or a “Hz” range. Make sure the slip rings are clean. Check the connections between pins 4 and 5
(or pins 1 and 5 on Microlite 2.8KW) on the regulator, as this can cause an output voltage of 55-60 VAC, even with a good regulator. When these causes have been eliminated, the regulator is likely defective.

Ghostman · 10-02-2019, 09:00 AM

NO it's definitely reading 66 amps. That's why I'm curious as to why nothing going to the surge guard. My unit is all in one surge guard auto transfer switch all in one. Going to recheck the generator side to make sure everything is tight.

Quote:

Originally Posted by twinboat

Maybe it was producing 66 volts.

That's not enough to switch over the auto transfer switch.

Where is the surge guard wired in, before or after the auto transfer switch ? If before it, like most, its not a factor in generator power.

Have you had the generator fuel filters serviced lately ? Could be a fuel problem not letting the generator turn up to the proper RPMs.

Ghostman · 10-02-2019, 09:02 AM

Surge guard has the auto transfer switch all in one. It definitely reads 66 amps. I must have a loose connection somewhere. Everything else has been checked. The generator runs fine and was recently serviced.

Quote:

Originally Posted by twinboat

Maybe it was producing 66 volts.

That's not enough to switch over the auto transfer switch.

Where is the surge guard wired in, before or after the auto transfer switch ? If before it, like most, its not a factor in generator power.

Have you had the generator fuel filters serviced lately ? Could be a fuel problem not letting the generator turn up to the proper RPMs.

Ghostman · 10-02-2019, 09:03 AM

The command center shows the amps being produced by the generator and the load that's put on it. It's showing 66 amps being produced but no load being put on the generator.

Quote:

Originally Posted by spdracr39

How can you have amps without a load ?

okcnewbie · 10-02-2019, 09:26 AM

Quote:

Originally Posted by Ghostman

The command center shows the amps being produced by the generator and the load that's put on it. It's showing 66 amps being produced but no load being put on the generator.

After reading up on the command center I think I can help clear up some confusion. I believe the command center just senses what the input is and then displays what is available based on this and the switch settings.
So in your case it likely believes that it has 66 amps available before it has to start shedding some devices.
It sounds like you're on the right track tracing through the transfer switch, etc.

twinboat · 10-02-2019, 10:52 AM

Then its displaying the " potential " to output 66 amps. Odd.

Its not outputting 66 amps unless everything is on and running.

Amps, like HP, are produced under load.

Solo_RV_Guy · 10-02-2019, 11:44 AM

Quote:

Originally Posted by Ghostman

The command center shows the amps being produced by the generator and the load that's put on it. It's showing 66 amps being produced but no load being put on the generator.

Uh... no. Generators produce voltage, and do so until their current capacity is reached (amperes). I think the semantics need review:

Amperes are a measurement of current flow. Watts measure the amount of current needed to perform mechanical work (motors, for example) or create heat (Newton's laws) whether the heat is the work product or a byproduct of the work. Voltage is *potential*. Georg Ohm may be long dead but his Ohm's Law is not...

I'm not intimately familiar with the exact unit that is reporting what you are seeing but based on the replies you've gotten so far I believe it is showing you the load-shedding point.

Are you handy (and safe) with a volt meter? Check for full voltage at the generator's circuit breaker terminals (load side), then again at the transfer switch or whatever device performs this function. Then apply a load (turn on the toaster or a waffle iron) and see if the voltage changes up or down or does not change. Let us know what you find.

bhammond1980 · 10-02-2019, 09:01 PM

Just had a similar situation. Started the generator but air conditioners would not start. I noticed coach power was still running off the inverter. After several minutes looking for the most complicated answer I found the breaker on the generator had flipped. Turned it on and everything worked. Hope your situation is simple.

Ghostman · 10-15-2019, 01:12 PM

Found my problem. All indications it was something simple and it was. Thanks for all the suggestions. I tried to highlight the wire that worked it's way loose on the generator side in the Surge Guard Auto Transfer box.