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AC Main Breaker Replacement/Relocation

DRynning

New Member
Good day Captains. I know the AC 30a Main breaker has been mentioned in older posts but will start a new, dedicated one here.
As I noted in my initial post on the Pub forum, replacement of the factory-installed residential breaker has been on my list, and we had an event last weekend that brings it to the top.

We arrived at the boat on a cold, windy, rainy Friday afternoon. All was well aboard and inside, we stowed gear for the weekend and powered up our primary dockside heat, two electric space heaters (one fan-driven and one oil-filled radiant). We're always mindful of loads when running these two devices; we plug them into separate 15a circuits, and avoid using anything else with high draw while they're running (water boiler, water heater, etc). About an hour later the main tripped. I braved the cold and sideways-rain and went out to the helm seat locker, found that the switch was in the tripped position as expected; I turned it Off, then back to On and the switch held that position (didn't trip). However, still no AC was present at the PDP above the desk.
Marina staff verified no fault at the dock tower and at the boat-end of Vixen's shore cable. A phone consultation with our ABYC electrician (who actually picked up while working on another boat!) got some speculative discussion about the failure cause, and he has put me into his queue to schedule replacing the main (what Boeing would call a "plan for a plan"); he'll also install a galvanic isolator and check our inverter hookups. He advised the Blue Sea Systems 8011 ELCI 30a AC Main Breaker is a good choice for our application.
The 8011 appears to be similar in function and features to the 1502 but with old-style white toggle switches. The 8011 has been deleted from the BSS online catalog, so it's probably superseded by the more modern-looking 1502; the 8011 is still available through some online retailers; prices are similar and either device would be okay for us.

I have three questions for this esteemed Forum:
1. Does anyone have experience with the BSS #8011 (or 1502) breaker, or recommend an alternative 30a AC main breaker?
2. I intend to install the new breaker in the quarter berth aft bulkhead as I've read others have done - any issues with that, assuming it's within the ABYC limit? (<10' from Inlet, I believe)
3. Does anyone have photos available of their solution to relocate the AC Main from the factory's (kind of ridiculous) original spot?

Thanks!
Dave
Vixen, 1981 M382 #260
 

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Hi Dave - a couple of years after we got Zia, we also had 2 of those electric heaters plugged into the outlets amidships starboard and port. Something blew and the AC on the Port side went dead. I didn’t realized it but our outlet above the refrigerator/icebox was a GFI outlet and when it trips it cuts all AC on the Port side. Initially had me stumped because I wasn’t plugged into that outlet.

Doesn’t sound like that’s your case because you said there was no power above the desk. Which I’m assuming is the starboard side, and I don’t think we have a GFI on the starboard AC circuit. Although maybe you do.

I too bought a Blue Seas ELCI to replace the household breaker for shore power. I got the uber modern (BSS# 1502) one because I was going to replace the main panel with similar design. Now I don’t think I’m going to replace the main panel with that design, but the ELCI is going on the aft bulkhead in the quarter berth, as you are planning and others here have done. I think we just need to be cautious when drilling/cutting the hole to avoid pipes and wires on the inside.

It’s in my pile of things to do this winter. I really do like that new location though: much more realistic for actually reaching it. The factory location is a little sadistic, IMHO.

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Dave, thanks for the info. I have a new Blue Sea ELCI awaiting my cabinetry work before it is installed by my electrician. As you suggest and Mark plans, I will put it in the cabinet above the aft nend of the quarter berth. There is also an ABYC YouTube video showing installation steps. Good luck.
 
Running 2 space heaters, assuming they are typical 1200-1500 watt models, is exceeding what is safe, imho. Even if on "seperate" 15A circuits.

A single 1500w space heater is pushing it as far as im concerned.

If they are small 500 or 600W models they should be fine.

The main breaker (and wire) is nominally 30A, but you should not push it to its limit, certainly not continuously, and the twist lock shore power cords often fail at less than 30A.

Boat fires due to electric failure and space heaters are very common, and I've seen several boats lost due to fire. It just isn't something to risk.

Relocating the breaker to the quarter berth is a good idea, and elci is the way to go.
 
I Did main 2 weeks ago.
Bought new el box at Lowes and made my own face plate
Place at old location.
It was the cheapest solution.
And my old CB didn't brake, just burn contacts.
It was household CB with snap contacts which never should be used on boat.

ItemsQtySubtotal
Blue Sea A-Series Elci Main Circuit Breaker - Double Pole 120v Ac 30a
SKU: BLU3106100
1$132.75
Subtotal$132.75
Grand Total$132.75
Thank you, Hodges Marine!
 
In 2014 I installed 400ah of LiFePo4 batteries as the combined house and starting source with the then current BMS system with relays etc.!
My reliance on a bilge pump with a float switch almost cost me the whole bank due to switch malfunction.
Since then I no longer keep the boat connected to shore power and all batteries and systems are off.
The batteries have remained at a high state of charge during the off season. November through May.
Previously I left a 40 watt solar panel to maintain the batteries. Clearly not necessary and I have discontinued the use.
All through hulls off.
What risks or unforeseen events am I am I missing?
 
In 2014 I installed 400ah of LiFePo4 batteries as the combined house and starting source with the then current BMS system with relays etc.!
My reliance on a bilge pump with a float switch almost cost me the whole bank due to switch malfunction.
Since then I no longer keep the boat connected to shore power and all batteries and systems are off.
The batteries have remained at a high state of charge during the off season. November through May.
Previously I left a 40 watt solar panel to maintain the batteries. Clearly not necessary and I have discontinued the use.
All through hulls off.
What risks or unforeseen events am I am I missing?
So is the bilge pump is turned off/disconnected also? If so, several unforeseen events. Packing gland, and the mast are probably mostly likely source of water.
 
On my vessel, the 12 volt system is kept charged with solar during the off season. The main DC system is turned off, but the previous owner installed diodes in such a way that I can keep the bilge pump turned on and use all battery capacity in case of water intrusion. Float switches are notoriously unreliable. I have used an Ultra successfully for 20 years. Others like the Water Witch, I think.
 
Terry

Do you have a schematic diagram of those diodes? That sounds like a very interesting idea.

Jim
 
You don't need diodes for that. Just connect the bilge pump directly to the battery (with an inline fuse) so that it has power when everything else is off.
Its possible the previous owner used a diode if the bilge pump is wired to the main breaker as well. For example, if there are 2 circuits, an always on circuit connected to the battery, and a second circuit to the panel-both to the same float switch and pump. In this case, if the switch activates the always on circuit, it could feed and energize the panel through the other, and a diode could prevent that.
But that would be a poor design, the diode reduces flow capacity of the pump, and would exceed ABYC 3% voltage drop requirement by a large amount.
 
Frankly, I never understood the system, just used it. Not great seamanship, I know. I will look at it more closely. Warren, I don't believe the diodes drop flow that much, but you typically know more than I.
 
Diodes drop voltage by .7 volts, or 5.8% of a 12v system. That would be added to the drop already in the wires, which is about 1 or 2%
 
Our electrician will meet me at Vixen next week to discuss and plan the mid-January job. He has suggested in addition to the Blue Sea Systems 1502, I might consider a Smart Plug ELCIBRKR30SS inlet ELCI breaker combo setup (ABYC E-11 compliant), which looks like it would keep the breaker out in the cockpit, although the separate breaker module could possibly be relocated to a more accessible spot, like maybe on the footwell side of the helm seat locker. It would require purchasing a new Smart Plug cable as well, which combined (at retail) drives part cost above 1 "Boat Unit", before labor. I like the idea of mounting the BSS 1502 inside at the quarter berth, but then I ask myself, "How many times have I actually had to brave the elements to reset the Main?" I can see benefit in leaving it outside, so we don't have to go up and down the companionway and crawl into the quarter berth to switch shore power on or off when departing or arriving at docks; assuming it's a weather-proof housing, that would eliminate having to remove stuff from the locker and kneel behind the wheel as we do today, in order to reach in and get at where the factory-installed breaker is.

Anyone else have any experience with this Smart Plug product?

Also, I'd love to see any photos of other AC Main breaker installations in the quarter berth bulkhead. I looked at the area yesterday and it appears Vixen's bulkhead there has no wiring or equipment on the aft face, just a ~1" thick foam/foil insulating panel. The little cubby there would either dictate mounting a 1502 below that (closer to my feet), or maybe inside the cubby on the actual bulkhead (?), or on the cubby's fwd wall, which would eat some space inside.

And a side note: I look with envy at boats whose AC inlets are mounted closer to midship - our inlet on the aft starboard cockpit combing makes it a stretch sometimes getting the 50-foot cable to a shore tower when visiting other marinas, so we carry a Marinco 12' extension which has so-far always solved that issue. I use a strain-relieving strap around a stanchion to give the cable a 180 degree bend since I haven't bought a 90 degree adapter, and that shortens the cable's effective length by about 2'. We're almost always bow-in, although backing in is an option when tying up.
 

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I have installed a Smart Plug. Fit perfectly where the old plug was. A good in vestment in safety. I have a galvanic isolator next in line in the cockpit aft locker. All the AC wires from there run though the cockpit combing. If you drop the outboard overhead in the 1/4 berth, you will find the wire runs. This spring I will in stall a Blue Seas ELCI in the quarter berth area. The wire will drop down into the "cubby" shown in your photo. I made a wood piece that fills the starboard side of the cubby opening, into which the ELCI will be screwed. Since the ELCI AC wires should not be open to fiddling, I will also insert wood blocking access to the back of the ELCI thru the cubby. I lose 1/2 of the storage back there, but it was meager and rarely used anyway. I will post photos of my small bit of cabinetry later.
 
Interesting. I installed the SmartPlug to replace my partially fried shore power plug about 5 years ago. After going to a good lecture by Nigel Calder wherein he pointed out all the benefits.

I thought Dave’s (DRynning) electrician was talking about that kind of plug. But no, he’s talking about an ELCI/Breaker combo thing that is made by SmartPlug.

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An interesting idea, but I think it would take up too much space where the plug currently is - it would require 3 different plug-sized areas. Or the breaker/ELCI could be relocated inside, but then why have the stainless/waterproof housing? Unless I’m getting something wrong, I think I like the idea of a normal SmartPlug connect on the outside and the Blue Sea style ELCI/breaker on the inside.

Nobody could ever accuse me of not spending enough $ on our Zia, but it seems like the multiple SmartPlug approach would also cost a lot more. Like at least twice as much.

Terry - I bought a back cover for the Blue Sea ELCI. It fits the irregular shape of the back very well. Screen grab below. Not sure if they make a similar cover for the Blue Sea 8011, but this one works well on our 1502.

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Oh, and HAPPY NEW YEAR everyone!
 
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Just an fyi on the smart plug. No doubt it is better than the nmea plug. But, there are examples of them catching fire and boats being lost. I think it is misinformed to think the nmea plug is unsafe, and the smartplug safe. Both require frequent inspections, regular cord replacement, and don't run either at full rated capacity for long periods.

Its good to see this attention to detail to fix a serious electrical deficiency. Good on everyone undertaking it
 
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