Converter tripping

[aatauses]

Hello,
I need a few suggestions and thought this is the best place to get them. Converter. When we move and hook up to a 30 amp all is fine. when we move and hook up to a 50 amp the converter breaker in the Rv will trip--when I reset it all is fine. I have narrowed it down to only when we move and it happens just the instant I flip the 50 amp breaker at the pedestal. After I reset the breaker in the rv all is fine for as long as we stay--only happens after we move and when I flip the 50 amp at the pedestal. Looking for areas to troubleshoot??
thanks
al
currently in MT

 

[Bogie]

Not exactly sure why this only occurs at 50 amp and not 30 amp.

First (with the power disconnected from the trailer) check that the screw holding the wire to the breaker is tight. If yes, you may have a weak breaker.

You say it happens only after you move, so I assume that after it happens the first time, if you cycle the 50 amp breaker again a second time at the pedestal, it doesn't trip. So, it sound like in inrush current issue. What is the condition of your batteries? If they are heavily discharged for some reason at the end of the move, the inrush current would be higher.

If you feel comfortable working in the breaker box, I think the first thing I would try is swapping the converter load to another equal size breaker temporarily to see if the that solves the problem. Be sure all the power is disconnected from the trailer before working in the box. If that resolves the problem, replace the original breaker.

If there is no change after swapping the load, I would check the condition of the batteries. If nothing there, the converter may be on it's way south.

Keep us posted on what you find.

 

[danemayer]

You could have a problem with the neutral leg wiring. A partial open on neutral can cause a voltage differential on the two hot legs, where one is higher than normal and the other is lower. If the power converter is on the lower voltage leg, and it's trying to boost your battery - perhaps because of a weak battery - it will demand a lot of amps. If the voltage is low, the amps drawn is high and could be tripping the breaker.

Why only when you plug in? It may just be that once the Power Converter stops trying to boost the battery, you're ok. And with a partial open neutral, things may be working almost well enough not to notice.

When on 30 amp, there is only 1 hot leg from the pedestal that's in use. So the voltage differential doesn't happen - although other problems can show up.

At this point, I'd suggest checking several things:

• Condition of your shore power cord at both ends. Look for heat damage or charring. If you have a powered cord reel, before taking it apart, you'll probably want to use a meter to check voltage on both power legs.
• If you have an automatic transfer switch that would have come as part of Generator Prep, the connections inside could be loose or the wires could be damaged from heat. Check with power disconnected.
• The incoming L1, L2, and Neutral wires on the back side of the main circuit breaker panel inside the coach.
• Connections at an inline EMS/Surge Protector if you have one.
• Voltage at outlets or devices assigned to L1 and L2. The hot legs alternate in the breaker panel.

Our Electrical User Guide has pictures and drawings that may help you through some of these checks.

If you do have a partial open on the neutral, it can lead to serious damage to devices inside the trailer. You should run this down sooner rather than later.

Let us know what you find.

 

[aatauses]

Thanks, I now have a few places to check--I had checked the wires on the converter breaker, but not the main breaker so will check that. I also had considered a weak breaker so not will also check that--really appreciate the suggestions
al

 

[wdk450]

Do you have an Electrical Management System protector or generator transfer switch (generator prep)? These have contacts that switch, and can arc&pit upon initial load activation/deactivations (turning ON the shorepower and turning OFF the shorepower). This could cause electrical problems that blow the breaker as you describe.

I personally have adopted a protocol of turning OFF the inside mains breaker BEFORE turning off the shorepower breaker when departing a RV site: so I arrive at the next RV site with the inside mains breaker turned OFF BEFORE I connect and turn on the Shorepower breaker. THEN I go inside and turn ON the inside mains breaker. This causes NO electrical loads (current draw) to be present on the EMS and Transfer switch relays (and even the RV site pedestal circuit breaker), preventing arcing and pitting. This way the electrical load arcing and pitting is limited to the inside mains breakers. These are readily available at hardware stores, easy to replace, and low cost. I carry a spare one with me.