Shore Power when docked

Electrical and electronic topics for small boats
Eddie
Posts: 1
Joined: Thu Mar 04, 2021 2:43 pm

Shore Power when docked

Postby Eddie » Thu Mar 04, 2021 2:46 pm

Hello all. [The author states he is a] [n]ew 2016 210 Dauntless owner [and that he has curiosity about the behavior of] folks [regarding if they] connect [their boat electrical power distribution wiring] to shore power when [their boat is] docked.

[The author also states that during] [m]ost time, my boat lives in saltwater
[and is] docked behind the house and is bottom painted.

[The author mentions that for him] to know the benefits and downside of using shore power would be helpful, [and the author wants] to confirm [the boat’s] bilge pump doesn't [discharge the boat’s] batteries.

hauptjm
Posts: 45
Joined: Mon Oct 19, 2015 3:26 pm
Location: New Orleans

Re: Shore Power when docked

Postby hauptjm » Thu Mar 04, 2021 4:44 pm

If all you are concerned with is the battery power to the bilge pump, then skip shore power altogether and use a solar panel trickle charger on the battery. The cost have come down on solar panels and you can forget possible electrolysis problems from using shore power.

Forgot to add: If you are going to use shore power, I would suggest a galvanic isolator, particular if you put into unfamiliar marinas.
Last edited by hauptjm on Thu Mar 04, 2021 4:49 pm, edited 1 time in total.

jimh
Posts: 11672
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Shore Power when docked

Postby jimh » Thu Mar 04, 2021 4:46 pm

Eddie—the only time my boat is at a dock with shore power is when I am living aboard the boat. I connect the boat to shore power at those times. I hope this is helpful in assuaging your curiosity.

For my use of shore power the benefit is the boat’s batteries are being charged.

I do not see a disadvantage from use of shore power in my application.

jimh
Posts: 11672
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Shore Power when docked

Postby jimh » Fri Mar 05, 2021 7:15 am

Regarding if a bilge or sump pump will discharge a boat battery when the boat is at a dock: yes, of course. The pump runs on 12-Volt DC power, and that power will be drawn from the boat battery.

If the boat is at a dock and if you connect to 120-VAC shore power and if the boat wiring includes a 120-VAC-powered battery charger, and if the battery that powers the pump is wired to the battery charger and if the battery charger is switched on, then the shore power 120-VAC power will be converted to 14-Volt DC and current will flow into the battery and the battery will be recharged, if the battery charging current over time exceeds the pump current over time.

jimh
Posts: 11672
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Shore Power when docked

Postby jimh » Fri Mar 05, 2021 7:29 am

If you want a further discussion of shore power wiring, please read the most recent American Boat and Yacht Council recommendations on connecting a boat power distribution system to shore power. If you have more questions after reading the ABYC recommendations you should start a new thread in the SMALL BOAT ELECTRICAL forum, and ask a specific question.

Please do not propose surveys of boater behavior, such as “Do you connect your boat to shore power?”

Your own behavior with regard to connecting to shore power or some other aspect of boating should be in accordance with your own needs, so what others need may not be the best guide for you. You may also elicit advice that is inappropriate or conflicts with regulations. Your behavior should be guided by regulations, not what another causal boater might do.

In the case of a boat kept at a dock in the water at all times, any sort of continual connection to shore power must be very properly done in order not to cause harm to the boat and to not cause electrical shock to anyone in the water. If you plan to use shore power at your own dock, you must provide that power in compliance with Electrical Codes for your municipality. You should also be insured against any claims for harm resulting from a fault in the wiring. You need to research the requirements for electrified dock wiring and have any wiring you install inspected and approved. Use of a ground-fault-interrupter (GFI) on the 120-VAC source is likely mandatory and also critical. More information on shore power and GFI can be found on another website.

This topic is very complicated. Again, read ABYC recommendations. Post specific questions to SMALL BOAT ELECTRICAL for any follow-up.

I also recommend you read these older discussions:

Risk of Low Voltage Electrocution from Swimming in Marina
http://continuouswave.com/ubb/Forum6/HTML/003778.html

Swimming Safety: NOT IN MARINAS
http://continuouswave.com/ubb/Forum1/HTML/019696.html

Also, since you have purchased a recently made Boston Whaler boat, you can anticipate that the boat wiring and boat electrical system are likely to be in compliance with federal regulations that apply to the electrical part of the boat. Whether or not your particular boat has an OEM-installed battery charger is unknown to me.