Newbie question: What happens if you turn on too many appliances?

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

thelazyl

Well-known member
Joined
Nov 9, 2018
Posts
600
Location
Molalla, Oregon
I have a 2003 Fleetwood DP with an Onan diesel generator.  As part of our pre-purchase inspection we turned on all appliances while the generator was running (including A/C, Microwave, TV and lights).  However I'd like to understand something simple:

What would happen if my generator lacked the juice to power all appliances - is the answer simple such as tripping one of the breakers?  I have a breaker panel inside the RV. 

I have the same question about the inverter.  I assume a breaker would trip?  Or, does the appliance simply not function?

I don't seem to have a manual that covers this specific question.  I have a generator manual and also a coach manual that talks about the breaker panel.  I can find the specific models of the generator and inverter if that would help.
 
First thing you will hear is the generator lugging down.  If you have a diesel generator its probably in the 5000 watt size.  Likely you have more generator than appliances, so I doubt you will see any problem.
Second you mentioned an INverter.  Do you actually have an INverter ot a CONverter?
 
Your generator is likely able to handle your RV just fine...However if you did overload it a breaker would trip either on the generator or on your service panel.

On our inverter...If you overload it it trips and alarms. I have to turn it off to reset and lighten the load then turn it back on.
 
As mentioned you will likely hear the generator lug down, lights may dim, and if you don't turn something off you will probably trip an output breaker on your generator.  Being an Onan diesel generator there are likely 2 output breakers mounted on the generator itself, one or both of these will likely trip if overloaded.  It is also possible that the generator engine will lug down to the point of dying before the breaker trips, this depends on how over-sized the engine is on your particular generator, and the elevation where you are operating it.      Engines loose power the higher the elevation (thinner the air is), so if you are high up in the mountains you may find the generator more prone to lugging down, than if you are at near sea level.  Typically 3.5% power loss for every 1,000 feet of elevation on non-turbo charged diesel or gasoline engines, which explains why my gas Onan 4000 could not power my microwave and air conditioner at the same time when I was camping out at 8,800 in a national forest campground in Wyoming a couple of years ago.
 
Anybody know when Fleetwood began installing the smart EMS systems?  Our coach has it and it has been great for us. We found ourselves plugged into 30 amps for four weeks in southwest Florida and did not trip a breaker once. It sheds loads in order you?ll notice least (rear AC then water heater then fridge then washer/dryer and lastly, front AC).  What?s not a protected circuit is the outlets.  I?m sure we could trip a breaker if we were making toast and coffee while microwaving and hair drying. I?ve seen it shed the rear AC when running the gen set, but not often and not for long.
 
The generator itself has a main breaker(s) that will trip if its max amp capacity is exceeded.  Further, most Onan gensets have internal monitoring that will shut the generator down if overloaded, e.g. voltage begins to fall or amp demand exceeds supply.

As others have mentioned, the genset will "lug down" and make a louder & deeper sound as load increases. This is normal, so it takes an experienced ear to guestimate when the "lug down" is nearly the limits.
 
With a generator it can lug own and stall. though it would be very hard to do that (In theory I can do it with my 5500 watt ONAN. in practice has not happened yet and .. it's a 2005)

IN practice I have had many a breaker to TRIP on me. some for no apparent reason (Vibration will trip the breakers used by ONAN. also Tripp-Lite)

INverter.. Again the breakers should protect but if they don't.. it shuts down and beeps at you.
 
We found out last summer that when running the AC (with compressor active) and turning on the microwave trips our genny breaker nearly instantaneously.  It was quite hot out, with AC cranking, and DW turned on the microwave.  I was sitting outside and nearly leapt from my chair when the genny began lugging (very noticeable).  Heard a bit of a click and it returned to normal, but power died. 

On the good side, I now know exactly where the breaker on the genny is located!

PS:  To be clear, this is NOT a breaker in the distribution panel inside, but rather a breaker right on the genny, behind an access door.  This is a gas Onan 3600, BTW.
 
if I run my AC and my microwave at the same time I throw a breaker on the generator, which is hidden in a rather hard-to-reach place, sadly.
 

Members online

Forum statistics

Threads
131,749
Posts
1,384,209
Members
137,520
Latest member
jeep3501
Back
Top Bottom