Shore power electrical panel Reverse Polarity

Benkovich

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I have a 2005 265 Express. When connected to Shore power indicates reverse polarity. There is no reverse polarity where the power originates from.
I'm thinking the house panel may need to be replaced? Any thoughts?
 

seasick

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Most likely the receptacle at the 'shore' end is wired incorrectly. If not, it is possible that the power panel in the boat is bad
 

Halfhitch

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Plug one of these into your shore power pedestal on the dock. You may need to use an adapter depending on what is provided on the pedestal. Don't rewire your boat until you verify that it is receiving proper circuitry.

https://www.lowes.com/pd/IDEAL-E-Z-check-Analog-120-Volt-Specialty-Meter/1003193136

Don't overlook the possibility that your own power cord could be the culprit if it has replaceable ends, and the installer did it incorrectly. If the pedestal checks out OK, then plug your cord in and plug that tester into your cord to make sure the reversal didn't happen in your cord.
 
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seasick

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Its also possible that someone wired a receptacle on the boat incorrectly
If you mean a shore power receptacle, then yes.
If a downstream utility receptacle (120v) is wired incorrectly, the power distribution panel won't know that.
 

Hookup1

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Check everything with a meter or bring a marine electrician in. It may be as the guys are saying that someone screwed something up. It could be the polarity check device in the panel but I'm not convinced yet.
 

Fishtales

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I'm with the others. Likely the plug on the dock is wired incorrectly. It could be your boat, which you can check fairly easily but given the year I'm guessing if it was your side, it would have been detected by now.
 

seasick

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A good point was made regarding the shore power cord by Halfhitch. If it has non-molded onto the cable connectors (either end) that could indicate that a connector was replaced and in that case, the wiring may have been connected incorrectly.
 

Fishtales

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I’d get a new cord if damaged or non functional. I’d never use a new plug due to water intrusion risk.
 

Benkovich

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I have a 2005 265 Express. When connected to Shore power indicates reverse polarity. There is no reverse polarity where the power originates from.
I'm thinking the house panel may need to be replaced? Any thoughts?
Thanks for all the feedback. I will check the dock receptacle. Everything was fine for 5 years until late summer. Does anyone know where I can get a panel for the boat if it is bad? My panel measures 4.5" x 7". The opening is 4" x 5.75".
 

seasick

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I am not 100% sure if the following steps will work but I would try it.
Assuming you have a 120v receptacle in the boat, get yourself a 110v plug in circuit tester. I have the small yellow one with 4 indicator lamps on it. They are available at Home Depot and similar stores and are something every home owner should have in the tool kit
Switch on your shore power and your breaker for the receptacle ( if you have them) and plug in the polarity tester. The tester has a label on it or writing that tells you what the various lamp conditions mean. If it shows the pattern for normal wiring/polarity , your panel is probably having a problem. If it shows reverse polarity, your panel is probably OK and the problem is in the shore power pedestal , the cord or the wiring in the boat between the panel and the shore power receptacle on the hull.
 

SkunkBoat

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Thanks for all the feedback. I will check the dock receptacle. Everything was fine for 5 years until late summer. Does anyone know where I can get a panel for the boat if it is bad? My panel measures 4.5" x 7". The opening is 4" x 5.75".
Blue Seas makes many sizes of AC panels.
They also have a description of the Reverse Polarity indicator.

Looking at the circuit it is just a LED diode(with internel resistor) between the ground and neutral. If there is a difference of voltage then the LED lights.
If the LED lights, the LED isn't bad. So there has to be a wiring problem. There is nothing to "go bad" in the panel to cause it to light.
The panel is just circiut breakers and wire and the indicators. There's no guarantee buying a $250 panel is going to fix anything

The Neutral and Ground are tied together in the marina's main panel. There should be 0volts between them.
If the ground on your boat is not connected at all to the marina ground it is possible to light the LED. Your boat has a galvanic isolator. if that is bad you could get that symptom.

You can find the way to test a galvanic isolator on the web...probably on the blue seas site...
 

wspitler

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On my 330 if there is reverse polarity the panel will not allow AC power to be distributed through the panel. I docked at a dock with reverse polarity on the shore side and couldn’t get any AC on the boat. Confirmed with a tester, fixed shore side, all was well.
 

Eltajin

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Thanks for all the feedback. I will check the dock receptacle. Everything was fine for 5 years until late summer. Does anyone know where I can get a panel for the boat if it is bad? My panel measures 4.5" x 7". The opening is 4" x 5.75".
I had this issue on a 2011 canyon last year. Marina checked their pedestal and was ok and prior year I had had no issue. The shorepower receptacle and galvanic isolator both looked to be in a bit of rough shape, so I just replaced those figuring regardless of the ultimate resolution it was needed. Turns out it resolved the issue. Both were easy to swap out and think it was like ~$99 for a marinco receptable and ~$250 for a new isolator. The wiring by the receptable showed some visible signs of corrosion so I did have to trim that back.