• Untitled Document

    Join us on March 29rd, 7pm EST

    for the CBEC Virtual Meeting

    All EYO members and followers are welcome to join the fun and get to know the guest speaker!

    See the link below for login credentials and join us!

    March Meeting Info

    (dismiss this notice by hitting 'X', upper right)

Electrical System - current capacity

K2MSmith

Sustaining Member
Hello, I am starting some basic maintenance on the boat at the slip (as a new owner). Some newbie questions. I can't find any references (manual or otherwise) on the current capacity of the 110v system on the boat. I would like to run a Winnex air purifier on the boat when I am not using it. It is rated at 70 watts, 1.3A. I am also running a dehumidifier (west marine). Since I am doing some maintenance on the boat, I will also be using a heat gun to remove varnish. That is about 1800W so I don't think I want to run that off the boat 110v system. Do they make adapters to convert your shore power plug to a standard 110V ?
 

1911tex

Sustaining Member
I may be miss-understanding your question about the shore power plug...it is standard 110V !! No adapters required. If you are concerned about overloading the 110V, when you use the heat gun, shut off the air purifier and dehumidifier. Someone else may understand your question better than I.
 

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
If you want to run appliances direct off the shore power outlet, rather than through the boat AC system, the usual solution is a pigtail.

 

K2MSmith

Sustaining Member
If you want to run appliances direct off the shore power outlet, rather than through the boat AC system, the usual solution is a pigtail.

Thanks Christian I will see if I can find one of those at westmarine sausalito... Do you know where to find the current capacity of the boat AC system ?
 

nquigley

Sustaining Member
If you're in your slip, are you allowed to run an extension cord from the dock pedestal's standard 110V socket to your boat - for your heat gun? (yes, they draw a lot of power, esp on the High setting). Our pedestals have both sockets: NEMA 30A for shore power cables and regular 3-pin 20A (15A?) socket for extension cords for temporary uses.
 

Parrothead

Member III
Your boat should have a 2 pole main breaker for the shore power and its amperage rating should be on the handle. That's for the whole boat though. Individual branch circuits could be less, also marked on their respective breakers. FYI, your 1800 watt heat gun draws 15 amps @ 120V all by itself.
 

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Our original AC distribution panel (under the DC panel) is old. Unless confident with AC (I'm not), it could use a check by an electrician, or at least somebody competent. Good time for that is when changing the battery charger.

The 38 has five AC outlets, one GFCI, with itsr own wiring system. We plug in heaters, heat guns, coffee makers and other high-current devices. Nobody has examined the breakers or wiring in years .

Many of our members have experience with "house current" and have no hesitation understanding and plunging into yacht AC wiring. I hire somebody.

AC is serious. DC will only kill you if you really deserve to die.
 

1911tex

Sustaining Member
Thanks Christian I will see if I can find one of those at westmarine sausalito... Do you know where to find the current capacity of the boat AC system ?
Here you go.....lots of choices:
 

K2MSmith

Sustaining Member
Here you go.....lots of choices:
Thanks 1911 (does that name come from the famous Colt 1911 ? :). I am finding an amazing amount of cool stuff the PO left on the boat (for example service records and every manual for every piece of gear purchased) , so I am going to look around. It's possible that I already have one but don't know it yet...!
 

K2MSmith

Sustaining Member
Our original AC distribution panel (under the DC panel) is old. Unless confident with AC (I'm not), it could use a check by an electrician, or at least somebody competent. Good time for that is when changing the battery charger.

The 38 has five AC outlets, one GFCI, with itsr own wiring system. We plug in heaters, heat guns, coffee makers and other high-current devices. Nobody has examined the breakers or wiring in years .

Many of our members have experience with "house current" and have no hesitation understanding and plunging into yacht AC wiring. I hire somebody.

AC is serious. DC will only kill you if you really deserve to die.
My knowledge is all about software not hardware - so I think your advice on the AC is a good one..I'll handle with care. I know my limits.

The boat has a "TrueCharge" charging system by Statpower. I have all the manuals. It appears that this was added later (maybe a long time after). I don't know if the boat originally came with a shore power AC system or not. I'm guessing not. On my dream list (near the BOTTOM) is to convert to lithium-ion and go with electric propulsion. Everything on my boat seems to have been nicely upgraded, except the diesel. I am going to get a baseline check on it next month as soon as the diesel mechanic becomes available.
 

markvone

Sustaining Member
The standard dock outlets are 30 amp and 50 amp with different plugs. The 50 amp cable has bigger wires inside. I'm sure all the Ericson's came with 30 amp cables and service. There wasn't that much AC stuff you HAD to have on your boat 40 years ago. The main AC breaker in the AC panel will be 30 amps, so that's the capacity. All your AC circuits (outlets, battery charger, hot water heater, 110v refrigeration, 110v Air cond. ) will have to share this 30 amps when running at the same time. The AC outlets are on a 15 amp breaker. You can split these into two different 15 amp circuits or just add an outlet on another 15 amp circuit breaker in an open space in the AC panel to power a specific item, I power a heater in winter. Now you can shut down the battery charger, hot water heater, reefer and A/C while you run two 1500 watt items at the same time. I sometimes also run an extension cord from the dock pedestal 110v ac outlet to get a third 1500 watt item if I'm running the heater, a heat gun and making coffee in winter.

Mark
 

Tin Kicker

Sustaining Member
Moderator
1800 W is just over 16A, so the size of the standard 30A dock cord should be fine.

That said, the historic vulnerability is corrosion in the shore plug that the dock cord plugs into. Below is not mine, but the back side of mine had started to brown. And when a plug overheats, the contacts weld so IF you are present, you can't just pull it apart.
bad-shore-cord2.jpg


When replacing mine, I did like a lot of others have gone to the SmartPlug:
 

Kevin

Junior Member
On a side note, while your circuits might be rated for 15-30A, these boats are old. So it wouldn't hurt to inspect some of the wires (make sure you're uplugged when inspecting). When I went to install my Smart Plug, I noticed that my AC wiring at the panel felt kind of brittle. As it turns out, ALL of the ac wiring on my boat had a disintegrating jacket problem when I worked it with my hand. Every place I checked it, at various outlets, I found the same scenario. In the picture below, the wires looked ok until I started flexing them and then the jacket just fell apart. I immediately replaced all of the AC wiring in the boat with Ancor stuff, and bought all new outlets.

1591509814335.png
 
Last edited:

Tin Kicker

Sustaining Member
Moderator
Yup. The early type of PVC used embrittled faster than the newer types.

The image below shows three issues with a single battery cable. The strands are all black because water got into the jacket and corroded them. The terminal had been just loose enough to move and the big green area to the right of the hole is arc damage and there were more on the other side. When the black tape under my thumb was removed, a pile of loose green crud was found.

Green or black = corrosion = resistance = heat downward into a failure
Loose connections do the same
20200606_155124-X4.jpg
 

CSMcKillip

Moderator
Moderator
Hello, I am starting some basic maintenance on the boat at the slip (as a new owner). Some newbie questions. I can't find any references (manual or otherwise) on the current capacity of the 110v system on the boat. I would like to run a Winnex air purifier on the boat when I am not using it. It is rated at 70 watts, 1.3A. I am also running a dehumidifier (west marine). Since I am doing some maintenance on the boat, I will also be using a heat gun to remove varnish. That is about 1800W so I don't think I want to run that off the boat 110v system. Do they make adapters to convert your shore power plug to a standard 110V ?
The AC Outlets have a 15amp breaker. See attached schematic for the Ericson 33RH
 

Attachments

  • ac back panel.JPG
    ac back panel.JPG
    86.9 KB · Views: 10

1911tex

Sustaining Member
Last edited:

Rocinante33

Contributing Partner
Since the heat gun is only used in your hand, you are obviously present, I would try it on your boat AC plug and see how it works. Does it trip the breaker? Probably not, but do it with everything else disconnected and stay aware of the breaker and any electrical or smoke smell, but it will probably be fine.

I have used a heat gun on my boat before with no problems, although it was not for an extended period....heat shrink tubing or loosening adhesive, etc.
 

supersailor

Contributing Partner
Be VERY careful increasing the amperage on the fuses on your AC panel. Terra Nova has 14 gauge wire from the stern plug to the panel. That wire is rated for 15 amps. Running the circuit in excess of 15 amps heats up the wire. To go to 20 amps, I would need to run 12 gauge wire. The reason you have the 30 amp shore cable is that is what most docks are rated for and they only provide that service. It is good for us as there is less voltage drop in the heavier cable.

I also have used a heat gun with no problems but that means using only the heat gun on the circuit. There is a good reason there are too many electrical fires on boats.
 
Top