Shorepower Compliance

[Chuck Bell]

Recent survey of my boat included the following finding:
"The AC shore power service has the following discrepancies: solid strand wire, AC grounding connected to the AC neutral at the service box, does not have the AC grounding connected to the vessel's bonding system, and has only a single pole 20 amp breaker. The AC shore power system needs to be revised and brought into compliance with the A.B.Y.C. wiring standards."
The current wiring looks to be original.
Do I need to completely rewire the AC system? Any suggestions on how to bring the current system into compliance? Practical advice will be appreciated.
Chuck Bell
CD27 #212, "Spirit"



cdbell@jersey.net

[John R.]

Recent survey of my boat included the following finding:
"The AC shore power service has the following discrepancies: solid strand wire, AC grounding connected to the AC neutral at the service box, does not have the AC grounding connected to the vessel's bonding system, and has only a single pole 20 amp breaker. The AC shore power system needs to be revised and brought into compliance with the A.B.Y.C. wiring standards."
The current wiring looks to be original.
Do I need to completely rewire the AC system? Any suggestions on how to bring the current system into compliance? Practical advice will be appreciated.
Chuck Bell
CD27 #212, "Spirit"

My opinion is yes, a rewire is called for. You need to have a dual circuit breaker handling both the neutral and hot supply circuits. The surveyor is correct regarding the safety issue of the AC ground being run to the ships common ground, which is also part of the bonding system.

ABYC code calls for the AC ground to be connected to the vessels common ground point. Some will argue this issue but AC circuit safety is of paramount importance to ABYC over other issues pertaining to the method of grounding and it's consequences. The principal argument against this method by some boaters is their concern over possible stray current leaks (see below).

1) ABYC standards calls for AC safety ground to vessel common ground point. No exceptions.

2)All solid strand wire must go. Totally unsuitable in a vessel due to lack of flex and vibration damage concerns caused by typical engine machinery.

3)Neutral momentary switch. This point is very overlooked by most whom wire AC circuits. There should be a reverse polarity momentary switch installed between the ground and the reverse polarity indicator light. That switch prevents current from flowing through the neutral circuit back into the vessel ground system and causing stray current. The lack of this switch is a frequent cause of the stray current problem people discover on some boats when the safety ground is connected to the vessels common ground. Cape Dorys did not have these momentary switches in their AC panels and should be retrofitted with one.


You need to comply completely with ABYC standards to meet requirements of most marine insurance carriers.

I don't know what year your CD27 is but I would assume from your description that it is not the original wiring from Cape Dory. I especially am alarmed by the use of solid strand wire.

[Bill Brockschmidt]

Chuck:
I recently purchased the ABYC publication "United States Coast Guard Electrical System Compliance Guideline" directly from ABYC. They have a web site. They are in the process of producing a new edition, so I was able to get the old one at a reduced price (I think $5.00). It is not a real easy pulication to use, but it does have a lot of information about required wire sizes, bundling,etc. If you are going to rewire the shore power system, it might help you get the whole system in comliance. It is also helpful for 12v systems.
Hope to see you on the Chester River soon.
Bill Brockschmidt
DULCINEA
CD28-#234



wbrocksc@friend.ly.net