330 Express- Upgrade Shore Power Connection?

themikehyde

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I was wondering if anyone has upgraded the shore power connection. Mine apparently has the factory 30amp, and running with the Cabin and Cockpit AC last weekend tripped the 30amp breaker on the marina pedestal twice. The surveyor recommended we upgrade to a 50 amp. Wondering how difficult it would be to pull a heavier wire and replace the breakers.
Mike
 

journeyman

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Since it was the marina pedestal breaker that tripped, that could be your problem. Bad breaker.

Was the AC the only thing running? Amps add up. My manual gives a general idea of what each thing draws for power. Plus there's the unknown draw on the outlets, hair driers etc.

If you upgrade your boat, you still have a 30 amp marina source. Just sayin...
 

Bayhouse

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^^^ X2 on the marina pedestal

I have a 2003 330 and in the marina routinely have the AC blasting, Fridge, HW heater on and using the stove at the same time. If I get greedy and try to use the microwave, i may trip to circuit breaker but not all the time. I couldn't justify upgrading to 50amp and I like to make upgrades to my boat.
 

themikehyde

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We were only running the two AC units (Cabin and helm). We have not had a problem at our marina, but we are under cover so have not had to run them as much as we did last weekend. It was very hot. I believe I will monitor it for a while.
Thanks,
Mike
 

Stampr

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I just bought a 330 grady express and would like to put cockpit air in , can u tell me the btu and the location of the ac and did u add a new pump and strainer .
Thx Bill
 

SkunkBoat

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as was said before, the marina has a 30 amp supply. Changing your boat to a 50 amp panel won't change that.

It IS possible that the marina breaker is tripping at less than 30 amps. You could try another outlet?
It is possible that you are drawing more than 30 amps at some moment when both AC units kick on and other things are on.

You could test that with a clamp on current meter and a wire splitter.
 

Fishtales

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We were only running the two AC units (Cabin and helm). We have not had a problem at our marina, but we are under cover so have not had to run them as much as we did last weekend. It was very hot. I believe I will monitor it for a while.
Thanks,
Mike

Not having the issue at your marina indicates it could be the marina's issue. As stated, maybe a weak breaker or something else on the supply side. If you have enough cord, try a neighboring outlet.
 

seasick

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One factor to take into account is that appliances that have a mechanical load like AC units, will draw more current if the supply voltage is less than normal. The supply voltage at the device will be lower due to voltage drop in the service feed ( in your case the shore power cord and / plugs and outlets). A too small gauge shore cord or a too long one will add to the drop causing AC units to draw excessive current. That can often lead to motor overheating and damage unless the device has protection circuitry).
The voltage drop is easy to check. Use a multimeter to measure the voltage at the dock receptacle, it should be 115 to 120 volts typically. Now connect your power cord and turn on your loads like the AC. Now measure the voltage at a 120 receptacle on the boat that doesn't have anything plugged in. Compare the voltage to the supply voltage. If more than 4% or about 5 volts, you may be getting into the risky area.
You boat's power panel may also display voltage. If it does checking is easier: Just turn off everything and note the reading. Then turn on the loads and see how much the voltage drops.

It is also possible that the supply voltage at your marina is low during certain times because you and OTHERS are running their AC units. Again, checking voltages at the boat will show that condition
 

grady33

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Check your connection at the boat. The twist on connection can sometimes be problematic over time. We have 50 amp at dock down to 30 amp connection and have never had a problem until recently when I got a reverse polarity light. Unhooked it and screwed it back on and was fine. I plan to replace the plug connection on the shore power cord at the boat.
 

themikehyde

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The outlet on the pedestal at my slip was discolored. I have replaced that receptacle, my shore cord and the outlet on the boat. Not taking any chances. Yes, I always cut breaker off when disconnecting/reconnecting, but apparently it was not done prior to me.