Turkey Day

[jack boats]

I got to the boat today for a Thanksgiving sail and noticed that my AC outlets would not power up even though the shore power was connected and the panel breaker was lit. I saw very lo ac volts on the guage and got to thinking my power cord had failed. I swapped it for a spare and no difference. So I try inverting and the AC outlets fire right up. So I try testing the breakers with a multimeter for the shore power and panel breakers and they all seem ok, albeit i'm not an electrician. So does anyone have any first impressions of what the heck is going on? I can only guess I'm getting a small AC charge through the shorepower connection, enough to light the switch on the panel but not enough to power the system? so do I have a bad connection somewhere? and how do I find it??

Happy Thanksgiving!

 

[Don12364]

First thoughts - dodgy shore power plug. If not that then a bad connection between shore power plug and mains panel. You might even be able to heat it arcing or fizzing.

 

[Dan Johnson]

I have a meter...

on my panel that tells me how much shore power voltage I have at my panel. It helps determining the "quantity" of power I'm supplied at "foreign" marinas.

One possibility is that you're getting shortchanged from your marina. The inverter power shows that the system is functioning properly.

Donaflex could be right too. As he said, listen for any sizzling behind the panel. Feel your shore power cable connections (both ends) for heat to see if you are the problem. Also a possibility--your hot or neutral wire in the cable has broken or pulled out of one of the cable connector terminals (happened on the boat I race on) or at the connector on the panel side.

 

[jack boats]

After checking the resistance of the cord and every breaker in between it and the panel, assuring the shore power was 220 thru the cord, into the panel. I was losing power somewhere between the shore power breaker switch and the rest of the system switches below it on the bus. Thats when Dick, the retired submariner electrician in the slip next to mine, told me to "Get some vodka because thats whats gonna keep you warm tonight."

I figured I was eff'ed through the holiday so I fired up the diesel to charge my bats. After an hour I took one last stab at the problem. It had to be a short but where? Hmmm, when I was dicking around with the panel the Aux car charger outlet sparked and the fuse blew, maybe that was the short? I turned on the shore power and still nothing then I started testing switches, and noticed on the AC bus, which isn't used because I don't have the AC option on my 420CC Hunter, that a little led glowed on one of the wires when testing but the same wire on the other Bus wasn't glowing when tested, I don't have a clue whats with that so I went to flip the shorepower switch or something and saw all systems check! Not sure what I did but things seem to be functioning again. The only issue now is a faint smell that seems different than the usual slight diesel odor I'm used too. So I think I want to get a pro in to check stuff out as soon as I finish all this Vodka.

 

[KD3PC]

that faint smell is likely burned/ing insulation or overheated breaker or panel....you REALLY must be careful..

not sure what you mean by "don't have the AC option" on your 420...you have AC somewhere on the boat, and it sounds as if you lost a "phase" somewhere along the way. Since you speak of 220 through the cord, one assumes you have a single 50 amp/220 VAC shore power plug...if that is correct then you have lost one side of the circuit or one phase. Or lost it for a while...this can only happen with an intermittent connection and they usually have high heat/smoke/fire or the potential for doing so.

I would find some one with experience to troubleshoot this much, much sooner than later, if in fact you are still plugged in...

to be honest I would unplug, until you do so...running the generator is not likely a good thing, as you are merely using that AC and bridging it to the AC panel on the boat...you may end bucking phases if you are plugged in and running the generator as well...since it seems that the breakers are not actually doing their job.

Please be careful
dave

 

[jack boats]

by AC I meant air conditioner. I don't have one of those or a generator so that bus on the AC panel isn't really doing anything i don't think. yea the smell is strange and makes me cautious. Until I get a pro out here, I'm shutting off the breaker at the dock box when I'm away. The thing about the smell is that when I stick my head into the compartment behind the panel I don't smell anything strong so it must be coming from somewhere else. I hope my wiring isn't toasted somewhere in the walls or wherever but its pretty hard to track these things down. My shore power cord is toasted so thats getting replaced tomorrow. All this originally happened while I was away so there was only the load of the Freedom Marine charger/inverter and the fridge on it. I shut all systems off when away. Its always something with boats and invariably at the worst times. The intermittent connection you mention could easily be coming from the fried cord so to be safe I should replace the slightly burned shore power cord connector on the boat too... lovely.