Shorepower Drops Out

[rmr911]

We've had our new boat in our new slip since February. Starting in April, we started losing the 30 amp service from the dock stantion. Disconnecting from the shorepower and waiting for a few hours got the power back on, only to fail again some time later. I tried a different power cord and the problem still occurs.

I moved our power cord to the connector on the empty slip next door and everything works fine and never fails. The marina staff are excellent and had an electrician replace all of the components in the stantion, and ultimately the entire stantion itself. Power came up perfectly on the new stantion, only to fail again by the morning of the next day.

So, new boat, new power cord, works great on my neighbor's side of the power box, fails after a few hours on my side of the box.

Ever seen such a thing? Any ideas?

 

[Alex F]

It's very possible that the other slip is on different line going to the main pannel. It might be using different/better breaker.

Is there a breaker where you plug your wire by your slip? Does this breaker trip or does the whole line of several other slips trips? I'm just trying to understand if this is a local problem just related to your slip or the complete line.

 

[DCarl320]

Move. :grin:

 

[rmr911]

Each "half" of the stantion has both a 30 and 50 amp breaker. Breaker never trips. The only symptom is that power drops out completely. Weird.

 

[boatmailster]

Looks like each side of post uses separate electrical phase and wiring on your side has some problem. Replacing cord will not help. Your marina may have to repair in-ground wiring.

 

[Nehalennia]

Is there any chance it's your Main Dist panel? Sounds to me that if you have new cords and new wiring from the dock, your boat is not handling it properly.
Try Disconnecting the power from the boat and seeing if your neighbor will trade and find out if you and he have similar issues or your boat drops out on his side.

 

[rmr911]

The 330 does have dual 30A inputs, but we don't draw enough to need the second cord. We run with one and "transfer" power to the right side of the distribution panel.

No significant power drains on the boat. Two fridges (cockpit and the larger of the two in the galley), and the battery charger. No AC or other drains on when we're not on the boat.

I thought at one time that the wiring on boat could have phases mixed up some how that was causing the wiring in the stantion to overload in a way that isn't flipping the breaker, but everything is copacetic when connected to the other side of the power box.

There have been a few wiring issues on the boat that the dealers fixed, which of course make you always looking for the next issue, but it's rock solid when not plugged into my own dock box.

Marina says today that they're ordering a new stantion...they agree that it should work the same on both sides of the box. I'm going to be really embarrassed if it turns out to be something in the 330's wiring!:smt017

 

[tobnpr]

The fact that you have no problems when plugged in to the power for the adjacent slip would certainly seem to indicate that the problem is not on your end.

I'm no electrician, but I don't understand how there can be voltage one minute, and none the next without a breaker tripping somewhere upstream. "No power" troubleshooting is generally pretty simple; the marina seems to have stopped this at the stanchion, but they need to verify voltage at the panel/sub-panel supplying voltage to your dock and trace it further back if necessary.
Let us know what they find...

 

[osd9]

Here's a stab...... the bad station has a loose connection....somewhere. While you are drawing current, things heat up just enough for the loose connection to lose continuity and falls out until it cools back down enough for the continuity to return.....hey...I said it was a stab!

 

[Alex F]

I'm no electrician, but I don't understand how there can be voltage one minute, and none the next without a breaker tripping somewhere upstream....

A simple answer is "the line", it's eather damaged and makes periodic connection or it's routed to a point where it could be disconnected like GFI outlets (just an example). Sometimes you find a GFI tripped and the whole line is out.

I used to be electrician, but I don't know how they wire up the marinas. If it's a dedicated line from the pannel to each dock, it's no brainer, change the breaker, test the line, if no good, change the line and review all connections.

Alex.