Shore Power Amp Service?
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corkscrew
- Engineer
- Posts: 140
- Joined: Wed Apr 09, 2008 5:05 am
- Location: Wilmington, DE Macgregor 26X 1997
Shore Power Amp Service?
Again, newbie - sorry if it's a dumb question. Many marinas offer 30 /50 / 100 amp service. Not sure what I need for my mac? I got a starting battery, deepcycle battery, and my big plug for the outside of my boat. Is this a really dumb question? I've always just plugged into a regular outlet ...
ModsEdit: just to clarify title ~fc
ModsEdit: just to clarify title ~fc
- Bobby T.-26X #4767
- Captain
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- Sailboat: MacGregor 26X
- Location: Oceanside Harbor, CA
Re: Amp Service?
unless you're running an airconditioner, microwave, elec heater, coffee maker , hair dryer all at the same time...you probably don't need anything but a standard plug into your Mac.
this is what i use to run on-board charger and a couple of outlets...

so, my cord has the standard female plug on the boat side, and the 30 amp male on the dock side (see picture below), connected w/ a 14 guage cord.

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki
this is what i use to run on-board charger and a couple of outlets...

so, my cord has the standard female plug on the boat side, and the 30 amp male on the dock side (see picture below), connected w/ a 14 guage cord.

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki
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Frank C
Re: Shore Power Amp Service?
Agree with Bob's advice. First & foremost, look at the receptacle on your dock and get a matching cord.
My marina just provides a simple outlet, same house-power 110v in a weather-box. A basic heavy-duty extension cord does the job.
My marina just provides a simple outlet, same house-power 110v in a weather-box. A basic heavy-duty extension cord does the job.
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Hardcrab
- Captain
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Re: Amp Service?
Bobby T is right on the money on one hand, but in looking around, the standard seems to be 30 amp connectors on both ends for boats our length in my area.
If you have any eye on resale down the road, the 30 just might be the way to go IMHO.
Wire size for a 30 amp circuit is 10 AWG. That's pretty heavy stuff, if you don't need it.
You can always reduce the wire size in the dock cable to agree with the circuit breaker/load you use, assuming you build your own dock cable.
14 AWG for 15 amp breaker.
12 AWG for 20 amp breaker.
Of course, by going with the 30 now, you will be covered if you decide to add something else to your electrical load down the road.
(Hubble makes a well made stainless steel receptical for the boat and the dock cable connectors for less than the usual cheap plastic stuff found at West Marine.
A google search should bring up the info).
If you have any eye on resale down the road, the 30 just might be the way to go IMHO.
Wire size for a 30 amp circuit is 10 AWG. That's pretty heavy stuff, if you don't need it.
You can always reduce the wire size in the dock cable to agree with the circuit breaker/load you use, assuming you build your own dock cable.
14 AWG for 15 amp breaker.
12 AWG for 20 amp breaker.
Of course, by going with the 30 now, you will be covered if you decide to add something else to your electrical load down the road.
(Hubble makes a well made stainless steel receptical for the boat and the dock cable connectors for less than the usual cheap plastic stuff found at West Marine.
A google search should bring up the info).
- Duane Dunn, Allegro
- Admiral
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Re: Shore Power Amp Service?
I installed the 15amp reverse plug inlet pictured above. It let's you use a standard extension cord. I picked up a yellow 50' - 12 guage one at Home Depot. The yellow blends with all the other overpriced marine cords on the dock and I like the glowing end at the inlet that confirms I have power. I bought a 30amp to 15amp adapter plug to use at the docks. Every dock in the Northwest I've been at over the last 8 years has had a the same 30amp twist lock connector (except a couple Canadian ones which had the standard 15amp outlets). Adapters are available at all marine stores.
This let's me use a standard extension cord plugged into a normal outlet here at home, and the same cord with the adapter at a dock. This makes it easy to keep the boat plugged in when on the trailer and the batteries topped up. It also gives me AC for tools, heaters and fans when the boat is at home on the trailer. It also let's me carry another extra standard 50' orange cord for those times when the yellow 50' is just not enough.
Inside my reverse plug inlet is wired to a marine double pole 15amp breaker. From there it goes to plastic junction box that feeds my charger, and a pair of outlets in the cabin. The first outlet in the string is a GFCI which protects the second.
This let's me use a standard extension cord plugged into a normal outlet here at home, and the same cord with the adapter at a dock. This makes it easy to keep the boat plugged in when on the trailer and the batteries topped up. It also gives me AC for tools, heaters and fans when the boat is at home on the trailer. It also let's me carry another extra standard 50' orange cord for those times when the yellow 50' is just not enough.
Inside my reverse plug inlet is wired to a marine double pole 15amp breaker. From there it goes to plastic junction box that feeds my charger, and a pair of outlets in the cabin. The first outlet in the string is a GFCI which protects the second.
- dennisneal
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Re: Shore Power Amp Service?
I bought a heavy-duty 30 Amp cable on sale at Waste Marine. I figure the voltage drop will be minimal with a big cord. I also bought a 30 Amp Marinco inlet box via Ebay. But, otherwise, inside the boat I'll run 20 Amps, GFCI, of course. Most of my household circuits are only 15 Amp. Twenty Amp service should be more than adquate.
- Chip Hindes
- Admiral
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Re: Shore Power Amp Service?
Sorry to rain on your parade, but there's a reason all those other yellow cords at the marina are "overpriced". They're sealed at both ends and waterproof when mated properly, covered in UV resistant vinyl, thicker, padded against chafe damage, and reinforced to withstand a substantially higher pull than a standard duty cord.
Water and electricity are not good companions, and the last thing you place you want to save a few bucks is on a cheap extension cord. Even if you don't electrocute yourself or one of your dockmates, stray current leakage due to inadequate electrical systems is a major cause of galvanic corrosion damage in marinas.
Our yacht club has had a rule prohibiting these for some time, but has not enforced the rule. One of the new members who is a licensed code inspector pointed out that kids (and adults for that matter) swim off the docks and that he considered it unsafe as long as there were standard duty cords being used. He also stated that it was at least a code violation and made both the club and the owner liable for a hefty fine. The rule is now enforced. I understand some marinas in our area are doing the same.
West Marine had these on sale for $40 last week. Do ourself and the rest of us a favor and either get the right cord or don't plug in.
Water and electricity are not good companions, and the last thing you place you want to save a few bucks is on a cheap extension cord. Even if you don't electrocute yourself or one of your dockmates, stray current leakage due to inadequate electrical systems is a major cause of galvanic corrosion damage in marinas.
Our yacht club has had a rule prohibiting these for some time, but has not enforced the rule. One of the new members who is a licensed code inspector pointed out that kids (and adults for that matter) swim off the docks and that he considered it unsafe as long as there were standard duty cords being used. He also stated that it was at least a code violation and made both the club and the owner liable for a hefty fine. The rule is now enforced. I understand some marinas in our area are doing the same.
West Marine had these on sale for $40 last week. Do ourself and the rest of us a favor and either get the right cord or don't plug in.
- pokerrick1
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- USAF M26X sailor
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Re: Shore Power Amp Service?
I also used the 15A Male Plug. To make installation easier, I replaced the knockout plug for the port stern rudder cleat. Adds a little more weather protection when the cord is plugged in.
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Kelly Hanson East
- Admiral
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Re: Shore Power Amp Service?
Well, you wouldnt want to do this actually.You can always reduce the wire size in the dock cable to agree with the circuit breaker/load you use
You want the wire size to match the rating of the dock outlet that you will encounter at home and on travels, which in NA is usually 30 Amps and occasionally 50 Amps.
You can plug a lower rated cord in using an adapter, but at my dock, if anyone sees this they will tell the dockmaster and it will be removed. Second time it gets cut in two.
I share Chip's feelings on the mixing of water and electricity.
What you do in your driveway is your business of course.
- Bobby T.-26X #4767
- Captain
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Re: Shore Power Amp Service?
OK...i give
one of these (50A - Y Adapter $500)...

and a couple of these (30A - 50' $80each)...

and plug on-board to a couple of these (30A $75 each)

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki
one of these (50A - Y Adapter $500)...

and a couple of these (30A - 50' $80each)...

and plug on-board to a couple of these (30A $75 each)

Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki
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Kelly Hanson East
- Admiral
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- Location: Kelly Hanson Marine........Mac 26M Dealer......Freedom Boat Works
Re: Shore Power Amp Service?
Someday Ill write the definitive treatise on shore power. Ive already got it titled..
Cutting the Cabal on Shorepower

Cutting the Cabal on Shorepower
- tangentair
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Re: Shore Power Amp Service?
Kelly Hanson East wrote:Someday Ill write the definitive treatise on shore power. Ive already got it titled..
Cutting the Cabal on Shorepower
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James V
- Admiral
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Re: Shore Power Amp Service?
Same problem with me. I have a 50 foot 30 amp cord and an adapator to change it to 15 amp. I also have a 25 foot 15 amp cord. Sometimes the 25 foot is too short. The problem that you can run into with the adapator is that it is not watertight and if you get rain you can be without power until it dries out. Try to find a special on 50 feet of 30 amp cord and get a good 25 foot 15 amp. Use the adapator inside the boat.
I cannot see you using 30 amps, at most 12. The distances from the power pole often is over 20 feet and often do not have 15 amp service.
If you are going to be using a local marina most of the time, check with them first.
the same with water hose. 25 feet is most often short. a total of 50 feet is best.
I cannot see you using 30 amps, at most 12. The distances from the power pole often is over 20 feet and often do not have 15 amp service.
If you are going to be using a local marina most of the time, check with them first.
the same with water hose. 25 feet is most often short. a total of 50 feet is best.
