Just so I understand your problem, are you saying that when you are plugged into shore power, you get surges on your 120V AC outlets unless you turn on all your 12V lights. Is this correct?
Also, when you say that you have tried different electrical outlets, do you mean that you have tried plugging your trailer into different shore power sources, or that you have tried different outlets in your trailer.
the way i found the problem was that i was trying to run the heater at night and the blower on the heater would run fast then slow back and forth quickly. When i turned on all the 12 volt lights in the camper it seemed to help.
yes i have tried different power sources to connect the camper to.
Okay, the first thing you should do is locate your breaker panel and turn off the breaker for the converter. Hopefully it is labeled. Let me know if you need assistance locating the breaker panel.
What other 120V appliances and/or 12V devices do you have turned on at the time?
Also, even though you have tried plugging the trailer into different outlets, make sure some of them are actually on different circuits, as we need to rule out a surge originating from the source.
i have located the breaker for the converter and i don't think i have any other devices turned on when the problem happens.
i have had the trailer plugged at my house and at my deer lease and it does the same thing.
Turn off all the breakers except the main one (the first one - 30A), then turn each of the others on individually until you find the outlet that has your heater plugged in. Make sure your 12V lights are off. This should result in 2 breakers being turned on, the main and the branch circuit that has the heater plugged in.
See if you still get a surge.
Do you have a battery connected to the unit?
I still get the surge and yes i have a battery connected to the unit.
Have you tried any appliances other than the heater?
the vent fan over the stove surges and until i get enough lights turned on the surge happens. Up and down up and down up and down...over and over.
The vent fan over the stove is 12V. I am assuming that the vent fan does not surge if you unplug the shore power?
i have a lamp plugged in and turned on and when the surge happens it does not surge.
that lamp is a 110 lamp.
Is the electric heater you were using 12V or 120V? Does this heater have a blower (motor), or is it a convection heater only?
If the heater is 120V, have you tried it in the same outlet as the lamp is plugged into?
Does your trailer have an inverter (as opposed to a converter)?
If we can rule out bad power, then lets make sure you test the heater in the other outlet, as it COULD be a GFCI issue. It may also be that your trailer is wired backwards (neutral to hot, hot to neutral). It could also be a bad converter transformer module, or a bad inverter, if you have one.
Does your cooktop vent fan surge when the shore power is disconnected? If it does, it is not the converter/inverter, or bad shore cord phasing.
Okay, disconnect your battery leads and see if the surging stops. If it does, your battery is probably the culprit. Your converter does NOT have the capacity to charge your dead battery, you will have to use an automotive battery charger for that, but first you should have the battery tested to see if it's faulty. It may be shorted out, which can cause the system to surge, since it will draw lots of power off the converter.
If the surging does continue with the battery disconnected, you may have a bad converter.
Okay, the only other possibility is bad power or EM interference, but since you have tried your trailer in two different physical locations, this would seem unlikely.
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