Generator Overload

[friz-5TH]

I have a 2004 Keystone Cougar 27 8 5th wheel. I also have a 2500w Champion inverter genset. If the 5th wheel is plugged into shore power, everything works fine. The coffee pot and the microwave overload the genset. Not together, using them separately. The coffee pot plugged into a GCFI outlet on the kitchen counter overloads the genset. The microwave has an outlet in a cabinet next to it. It overloads the genset. If I run an extension cord to a wall outlet, the coffee pot works fine. The same with the micro wave. The converter looks original. It is a Parralax model 7355 55 amp. There are 4 circuit breakers not including the main breaker. There are 5 labels under the breakers? The breakers do not correspond to the labels. It is screwy.
As This 5th wheel is 21 years old, I have owned it for 7, no telling if someone has rewired the breakers in the past.
This is the first trip I have used a genset.
So do I have a wiring/outlet problem or has the converter gone bad or are there bad circuit breakers? Thanks

 

[Viper02]

If you had a clamp on amp meter that measures AC and DC amps you could test the 120 VAC side at the circuit breaker panel at each breaker to determine the actual 120 VAC AMP load on each circuit in the fifth wheel.. Then troubleshoot from there based on your findings.... There are many sources for a multimeter with both AC and DC amp reading using clamp for connection

 

[JRTJH]

There are THREE "things" that you didn't mention that almost always are issues overlooked by owners when using a small generator and experiencing "overload problems"...
1. The water heater electric function, if turned on, is a "silent user of 1100 watts" from the generator.
2. The refrigerator, if it's a "typical RV gas/electric type" will automatically switch from gas to electric as soon as there is a "generator or shore power source". That's another "silent 400 watts" from the generator.
3. The converter/charger will automatically come online as soon as power (generator or shore) in the bulk charge mode for approximately the first hour. That's another "approximately" 950 watts from the generator.

So, the "other stuff that's automatically using generator power" IN ADDITION TO THE MICROWAVE AND COFFEE POT add up to as much as 2450 watts (just below the generator maximum) before you even plug in the coffee pot or attempt to set the microwave clock or power it on.

Check your "hidden generator power "leeches", they're most probably your problem.

 

[NH_Bulldog]

The converter ONLY converts 120v AC to 12v DC. It does not power your microwave or your coffee pot, or any 120v AC appliance in the RV. The converter is actually plugged into the Power Center and runs off a breaker like any other 120v AC circuit.

I agree with what John mentioned in regard to all the loads on that generator (which realistically outputs for 15-20A max). I would suggest turning the converter off at the breaker, then try using the appliances with the generator and see how it handles it. Also keep in mind that a 2500w generator is the surge rating, not the run rating, which is typically only around 1800w. So with that in mind, you can see how easily your generator can become overwhelmed.

As for the broader electrical panel layout, based on your picture, you have 6 labels but only 5 breakers (one of which is the main breaker), so I would guess that a prior individual did some electrical work. MAIN is obviously your main power breaker at 30A. AIR is for the air conditioner and should be a 20A breaker. GFI is for the duplex outlets in the camper and should be a 15A breaker. MICRO is for your microwave and should be a 15A breaker. REC/CON is for the converter and should be a 15A breaker. HOT WATER is for the electric heating element on a gas/electric water heater and should be a 15A breaker. These are "typical" ratings and may not necessarily match how your particular camper was originally wired.

Now, all of that being said, you need to do a little more digging to trace/test the actual circuits to determine what is getting power from what breaker. The size of the breaker also corresponds to the size of the wiring. For example, white Romex wire is 14ga and is matched to a 15A breaker, yellow Romex is 12ga and is matched to a 20A breaker and orange Romex is 10ga and is matched to a 30A breaker. You CANNOT interchange wires and breakers (put a 14ga wire to a 20A breaker). This will create an extreme fire hazard.

If you are not comfortable around electricity, you should consider having a qualified electrician take a look.

 

[flybouy]

Just one other consideration, the rating of the generator. Is the generator rating you posted (2,500 watts), is that running watts or maximum watts? If it's running watts then you have around 21 amps available. If thats MAX watts, then it could be as low as 15 amps depending on the continuous or running Amp rating. If you reference John's post #3 you'll see it doesn't take many items to exceed that generators capacity.

 

[jxnbbl]

I run the following generator:

https://a.co/d/i4Vdmys

with no problem with actually multiple of the items specified. If you have an EMS that gives you the power draw I would plug that in turn off all the breakers and then flip on the circuits you want on for the outlets. With nothing plugged in you should have 0 as the amp/watts used. Then run the microwave and write each down. I suspect something is hard wired to the circuit that you don't know about.

I run one AC on this generator. Additionally if this is new to you...when there is high load (AC in my case)...the 15k unit not the small one....I can not use "eco mode".

last I have installed softstart to make this work with the AC

 

[snoobler]

That 2500W generator is only rated for 1850W continuous, so even just the microwave @ 1600W (for 1000W output microwave) is getting close to the limit.

The converter is also powering DC loads at only about 85% efficiency, so 85W of DC loads is going to consume 100W of generator power.

Lastly, generators lose power with altitude. There's about a 3.5% loss of power per 1000' above sea level.

 

[jxnbbl]

I looked at this again this morning. Can you describe what you mean as "overload". One thing that has been bugging me - "If I run an extension cord to a wall outlet, the coffee pot works fine." When looking at the pictures it looks like you are using a light duty ungrounded extension cord.

 

[friz-5TH]

The converter ONLY converts 120v AC to 12v DC. It does not power your microwave or your coffee pot, or any 120v AC appliance in the RV. The converter is actually plugged into the Power Center and runs off a breaker like any other 120v AC circuit.

I agree with what John mentioned in regard to all the loads on that generator (which realistically outputs for 15-20A max). I would suggest turning the converter off at the breaker, then try using the appliances with the generator and see how it handles it. Also keep in mind that a 2500w generator is the surge rating, not the run rating, which is typically only around 1800w. So with that in mind, you can see how easily your generator can become overwhelmed.

As for the broader electrical panel layout, based on your picture, you have 6 labels but only 5 breakers (one of which is the main breaker), so I would guess that a prior individual did some electrical work. MAIN is obviously your main power breaker at 30A. AIR is for the air conditioner and should be a 20A breaker. GFI is for the duplex outlets in the camper and should be a 15A breaker. MICRO is for your microwave and should be a 15A breaker. REC/CON is for the converter and should be a 15A breaker. HOT WATER is for the electric heating element on a gas/electric water heater and should be a 15A breaker. These are "typical" ratings and may not necessarily match how your particular camper was originally wired.

Now, all of that being said, you need to do a little more digging to trace/test the actual circuits to determine what is getting power from what breaker. The size of the breaker also corresponds to the size of the wiring. For example, white Romex wire is 14ga and is matched to a 15A breaker, yellow Romex is 12ga and is matched to a 20A breaker and orange Romex is 10ga and is matched to a 30A breaker. You CANNOT interchange wires and breakers (put a 14ga wire to a 20A breaker). This will create an extreme fire hazard.

If you are not comfortable around electricity, you should consider having a qualified electrician take a look.

Very good info and yes I am quite comfortable around AC and DC. "I would suggest turning the converter off at the breaker, then try using the appliances with the generator and see how it handles it.". I had a misconception about the converter and the Main breaker. I thought the Main breaker controlled AC and DC. Apparently not by your statement. It only controls the DC which is what the name implies. Thanks for the info about Romex colors. I never noticed that 2 of the breakers are 15A and 2 20 amps. Thanks again.

 

[wiredgeorge]

I have a 2004 Keystone Cougar 27 8 5th wheel. I also have a 2500w Champion inverter genset. If the 5th wheel is plugged into shore power, everything works fine. The coffee pot and the microwave overload the genset. Not together, using them separately. The coffee pot plugged into a GCFI outlet on the kitchen counter overloads the genset. The microwave has an outlet in a cabinet next to it. It overloads the genset. If I run an extension cord to a wall outlet, the coffee pot works fine. The same with the micro wave. The converter looks original. It is a Parralax model 7355 55 amp. There are 4 circuit breakers not including the main breaker. There are 5 labels under the breakers? The breakers do not correspond to the labels. It is screwy.
As This 5th wheel is 21 years old, I have owned it for 7, no telling if someone has rewired the breakers in the past.
This is the first trip I have used a genset.
So do I have a wiring/outlet problem or has the converter gone bad or are there bad circuit breakers? Thanks

Somebody replaced the original 30/20A breaker which is MAIN/AIR CONDITIONER with a single 30A. If your air conditioner works, then they messed around with the wiring to the breakers. When I first bought our 2002 with a Parralax AC panel/converter it was 45A but basically the same as your's. I swapped the 30/20 (main and A/C) for a 30/15 and connected the GFI to the 15 and moved the 20A A/C to pair with another dual breaker. My power center ended up melting this past year and I installed a WFCO WF-8955 which is pretty much a replacement for the old Parralax which is very obsolete. Fit right in where the old one went and all wiring could be done with the AC/DC distro and converter outside the cabinet where it mounts so install wasn't horrible.

I bought the WFCO unit on eBay for $188 and found out that WFCO won't honor warranties unless you buy it from one of their approved dealers/sellers and eBay ain't that. Hopefully won't have an issue and it has been in use for a few months. Only issue I had was one of the burnt fuse red idiot lights stays lit even though the fuse is fine and that DC circuit works fine. Not a big thing but thought I would mention this.

 

[NH_Bulldog]

That makes perfect sense George, and now that you said that, I can decipher exactly what I see on the OP's photo. Where the breaker labels are, there are solid lines and dotted lines between each of the labels. The solid lines indicate a physical breaker space, and the dotted lines indicate that it is a split dual breaker (I call them piggyback breakers, but they also go by tandems or twins).

It is definitely worth opening that panel up and seeing what kind of wiring the prior owner rigged up in there.