ac electrical problems R-29cb
- Thread starter Eloc
- Start date
Do you have any breakers closed on the AC side.
Eloc
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- FMLT2907E617
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- Free Bird
I turned them all off and the panel breaker would not reset. I disconnected shore power and it would reset. When i turned shore power back on it kicked off again.
It sounds as if you have a short to the busbar. Disconnect shore power then I would pull the panel out a bit and see if you can see anything obvious. If it was me I would reconnect shore power see if it trips you may have move the wire tripping the breaker. If you are not comfortable dealing with AC power get a professional in.
Submariner
Channel Surfing
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Try plugging into a different shore power pedestal, assuming your'e on the dock. Also, borrow someone else's shore power cord and try theirs.
Brian John
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The circuit breaker is after the cable connector and feeds to the panel. DO NOT CONSTANTLY reset the CB (circuit breaker) after a trip. If this is a dead short on the load side of the CB (which it has to be if it is tripping). This will damage the CB.
WITH POWER OFF
You need to access the back of the AC Panel and see if there is a short.
Look for any signs of arcing or sparking. If none
Disconnect the load side bus or cable.
With the power off, try to rest the CB. It could be a defective CB.
BE CAREFUL. If the CB resets turn the AC Power from shore on, and with the load side disconnected, turn the CB on and see if you have 120 VAC AC on the line and load side.
Does this tug have dual power cords?
With all the load CBs off and the Parallel CB off, there has to be a short on the load side distribution for the circuit breaker.
WITH POWER OFF
You need to access the back of the AC Panel and see if there is a short.
Look for any signs of arcing or sparking. If none
Disconnect the load side bus or cable.
With the power off, try to rest the CB. It could be a defective CB.
BE CAREFUL. If the CB resets turn the AC Power from shore on, and with the load side disconnected, turn the CB on and see if you have 120 VAC AC on the line and load side.
Does this tug have dual power cords?
With all the load CBs off and the Parallel CB off, there has to be a short on the load side distribution for the circuit breaker.
Mastercraft
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I have an R29 2017. Four years ago, I was sharing shore power with another boat, 24/7 for months. Everything was fine, until it got down to 10 deg. I was tripping the shore power breaker as soon as I turned on the 110v breaker in my boat. Andrew Custis figured it out for me in a few minute call. The two boats were using electric heaters, using too many watts. 10 degrees and no power was freaky.
Eloc
New member
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- Jan 8, 2026
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- R-29 CB
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- FMLT2907E617
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- Free Bird
The boat has 2 30-amp services. I have checked the cords at the boat and both are delivering electric to the boat as they should. I have tripped all the individual breakers on the #1 panel and left the #1 panel breaker on. The #1 panel main breaker will trip once I turn shore power back on. I did have a heater plugged in on that panel. However, I ran a drop cord for that heater and the problem still exists. With all the individual breakers on panel #1 turned off, the main disconnect on that panel will still trip!
I appreciate all the help. Thanks much!
I appreciate all the help. Thanks much!
Rode Trip
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I'm not familiar with that boat's electrical system. Is the main breaker that's tripping an ELCI breaker, or is this a main breaker on the panel after the ELCI at the inlet? If it IS an ELCI breaker, then you need to look at the possibility of a ground fault rather than an overcurrent situation.