120v service dead

[Chasemmc]

Stopped by boat to check up after 20 degree night to find 120v service dead on my 81 56my. Checked fuses, they test okay. Checked all breakers, non tripped. Connected shore cord to starboard side, source 1- nothing. Put it back to port, nothing. Shore breakers not tripped. Running 3 - 1500w oil radiator heaters. Outback inverter running showing 98 percent on battery. Help please

[Boatsb]

First blame Randy.

Next.

Is there power going to the cords?

120 and 240 volt?

[Boatsb]

Run the engines if their not winterized. Get them as warm as possible and let them keep the boat warm for a day or so.

[Pascal]

Start at the source and check for power at the pedestal using a multimeter. Then at the end of the power cord

Some marinas have an extra circuit breaker before your pedestal, this may have tripped

[Chasemmc]

Put a multi meter on the pedestal, read okay. At end of 50a cord, okay. Checked continuity of fuses, okay. Nothing on the main panel, volt meter reading zero.

[Bob Bradley]

Are you using normal cords or the "smart" cords? The smart cords can trip internally.

[Boatsb]

Is there a fuse or breaker by the power inlet?

[krush]

A meter can LIE. Put a load on the circuit and then check with your meter. If there is a bad connection, it often won't show up with just a meter alone.

[Tim Powell]

First blame Randy.

Next.

Is there power going to the cords?

120 and 240 volt?

I second hat..
After holding prayer with Randy is there a round glass or clear plastic round screw on under the plug in. there is a fuse inside it. Do you have current at the end of the cord.

[racclarkson@gmail.com]

Check for GFI's. I had similar issue and had to go looking for a hidden GFI reset. It was really challenge to find that one.

[Chasemmc]

Got too dark to continue. Will go tomorrow and put a load on the cord. Then what do you think about taking off the cover on the distribution panel and start checking continuity starting with the rotary switch?

[Pascal]

If you have power at the cord then try opening up the panel for the fuse holder and testing for power there By guess is an issue around these damn fuses. The fuse may be good but corrosion or an issue in the holder especially inderload will be an issue

I don't understand why anyone bother with the fuses when they can easily been replaced with safer, more convenient and more reliable circuit breakers

[MikeP]

As mentioned, sounds like the GFI breakers tripped. did you check them? I assume you have them on the AC panels as per our 53. If they trip you will have no power until they are reset. It's hard to believe that a main circuit rotary switch/associated wiring suddenly went bad.

I agree that it COULD be poor fuse connections though seems unlikely that the fuses in both inputs 1 and 2 would have the same problem at the same time. But if it's not the GFI breakers, I would pull the fuses, clean the brass ends and the connectors in the fuse holder.

I don't share the negative view re fuses BUT they do require periodic cleaning and a smear of silicone grease on the connecting points and the threads of the screw-in fuse connector. I've never had a main fuse blow on the boat in the 12 years we have owned it.

[racclarkson@gmail.com]

To amplify on the GFI, I have GFI's on main panel for the port/stbd 120V lights and receptacles. This would cover where your space heaters are powered. But, big but, for reasons unknown there are GFI's downstream of the main panel (not in heads or galley). Any ground fault or overload will trip these first. Don't forget tired breakers/GFI's. They weaken with age. Just replaced double pole 50 on shore power inlet tripping before load was near max amps. Always tripped in winter. What do your rotary switches have to do with anything? Aren't they D.C. only?

[Chasemmc]

The breakers on the distribution panel to the left of the lower helm are not gfi. The AC breakers in the panels in port & starboard ER are not gfi's. Where else might their be breakers, behind the distribution panel? In the generator room?

[Chasemmc]

The whole boat is dark, not just one circuit.

[Chasemmc]

I read somewhere that the neutral leg is fused. Is that right?

[Boatsb]

All legs are per abyc I believe since the 80's

[racclarkson@gmail.com]

Unfortunately, if there are GFI's in line you'll have to trace the wiring. Mine were below the main cabin panel.

[racclarkson@gmail.com]

You never mentioned your 240V circuits. Are they also dead? If you can power up your stove it sounds more and more like a GFI issue. If no power to stove it's not going to be a GFI fault. You know there's a main breaker at the shore power cable terminus, right? It'll be a double pole 50.

[MikeP]

SO your main panels, to the left of the lower helm do NOT have a set of white-colored GFI breaker switches and associated master breakers at the bottom of the panels? On our 53 they are located there and will gang-trip if there is an issue. On rare occasion, they will trip if there is a marina power surge after a marina power outage. The pic shows our panel and white switches are the GFIs. If they trip, so do the ganged master breakers to the right of the white switches. The ganged masters supply all the AC power for whatever that particular panel controls. Depending on what caused the tripping, ALL the master breakers could trip.

NOTE: re the comment that rotary switches might be DC - there are 5 rotary AC switches, as shown on the panel. But as I said earlier, it seems unlikely to me that one of those switches failed. BUT...be sure they are in the proper position to select shore power from the correct input! Sorry if that sounds insulting but MAYBE somebody came on board and switched them "off" or to "generator" for some reason?

[bobk]

Re GFI's, we lost power to both aft heads which had GFI outlets. I traced it to a GFI outlet near the stern on the aft deck. It was full of salt probably due to years of the station wagon effect.

We also lost all power when one (or both) of the large fuses corroded. They tested fine with a multi meter. Just needed to clean the contact surfaces and apply some WD-40 and then clean the mess in the refrigerator/freezer. Cleaning these is now on the annual to do list.

Bobk

[racclarkson@gmail.com]

Well I learned something anyway. I don't have any rotary style AC switches on my 1983 55C. So that clears up a few things in this post. Thanks

[dottieshusband]

Well the good news, it's not supposed to get below freezing for at least a week! I run 2 50's on my power, so I don't use the 120v service inlet. If I don't get the illuminated red power indicator lights in the appropriate spots, after checking the pedestal and cord, it's always been the bayonet fuses at the inlet. If memory serves me, I believe there are breakers on the isolation transformer..Good luck..lectrical probs are the worst!

[Chasemmc]

I plug into the 240v 50amp as well. I found the isolation transformers in the generator room, but haven't found any breakers or fuses. Their is a source 2 breaker box mounted on the wall, but the power is going into Source 1

[dottieshusband]

I'd start the generator and power up the boat. That will give you a clue. If it all works on the generator, then you'll know it's on the input side.

[MikeP]

"If memory serves me, I believe there are breakers on the isolation transformer..Good luck..lectrical probs are the worst!"


On our 53 if you are facing the pair of transformers, which are located in the aft end of the Genny room, the breakers are just to the left of the left transformer, mounted on the same "shelf" as the transformers. They are NOT on any of the boat's electrical panels, they are just mounted in a box with the breakers facing upward.

[Chasemmc]

Today's progress:
Ran the generator and everything came up.
Pulled the power cord apart and retested with multimeter.
One leg, 120v, the other leg 19v. Same readings using the common and ground.
Plugged marina side into another pedestal, same results.

If one leg at 19v, would this stop the isolation transformers from working at least a little?
Going to reseat the wires into the plugs and see if the problem is with the connectors, otherwise might be in wire itself.

I`ll keep updating with progress

[Pascal]

Well if you have 19v on on leg of the cord you found the problem! Try a new cord

[racclarkson@gmail.com]

Or marina power problem. It wouldn't be a first. How about other boats? How about other docks?

[MikeP]

As Pascal suggested back at the beginning, did you check the power AT the marina end (the pedestal cord socket) with the meter to see if there was 120/120 present? Checking that immediately after checking your fuses/breakers would have been a good thing! ;)

[Chasemmc]

I thought i had checked it. I guess i tested the same leg twice. Would 19v on one leg shut the whole thing down?

[Boatsb]

It would if it's outside the input window of the transformer.

[krush]

Electricity flows through wires. It's kind of like pipes, but with electrons. You know the valves have to be open in pipes and you can't have leaks.

There are different types of pipes too, and branches. And you could have high pressure in a pipe, but when you try to actually use water, the pressure drops to 0, but then when you shut off the sink valve, the pressure goes back up.

Also, do piss on electric fences.

[MikeP]

or don't! :)

[krush]

or don't! :)


HAHA, my mind was saying "don't" but I somehow typed "do"...but now it looks more funny after the fact so I'll leave it LOL!

[tonytrakovich]

If this is a 125 / 250 volt cord and your boat has isolation / polarization transformers then one bad leg will shut down your 120 and 240 volt power.Trying another cord is the fastest way to see if it is the cord. Or first check the ends of the cord. Pull connectors off and look for discolored or brittle wires. They should look kinda Britt silver or copper. If they look blackish or blueish colored then cut the wire back and re-rerminate. You may have to cut back 2 feet or more to get to good wire. Heat build up at the connectors will ruin the wire and turn it black and make it brittle. Water intrusion will turn it green blue and make it brittle. If the ends look good, inspect the cord. A pinhole in the cord that goes through the outer jacket and the insulation will locally corrode the cord.

[Chasemmc]

Their are two transformers in the generator room. The service options are supply 1 -240v, supply 2 -240v, and supply three 120v. I understand the transformers are there to protect the boat from surges in the marina service and i guess a bad leg in the 240v supply.

How do they work?

[Freeebird]

First blame Randy.

Next.

Is there power going to the cords?

120 and 240 volt?It wasn't me, but we had the same issue at Goose Pond when we were connected to shorepower on the starboard side. After having the marina guy check the pedestal, we found out the problem was us. Connecting to the port side cured the problem, but it sounds like it was contagious.

Don't know if that will help anybody with troubleshooting this, but I thought it might help to have a little history lesson. Sorry I didn't see this before now.

[dottieshusband]

Their are two transformers in the generator room. The service options are supply 1 -240v, supply 2 -240v, and supply three 120v. I understand the transformers are there to protect the boat from surges in the marina service and i guess a bad leg in the 240v supply.

How do they work?

I'm not looking ap mine now, but it's the same vintage as yours, '87, the PO on mine marked the 1,2,3..1p, 2s, ..1 is 240 Port side, 2 is 240 Starbord side, etc. the red indicator lights, tell me the pedestal and line set are good, the the voltage dial and amp meter tell me what volume age etc. my top rotary switches selects input power source, my bottom rotary switches select PANEL (top or bottom) power source. So if both 50's are on the port side, my top rotary switches are both on source one. Then to run the top panel of circuits off one of the 50's, I set the lower rotary switch on source 1, and to run the lower panel of circuits on the second 50, I select ssource 2.. If I only had 1 50 amp cord, then both lower panel rotary switches would be set to the same input source. Likewise, if you have one 50 port side and one Starbord side, the top rotary switches would be source 1, and source 2, and the bottom would be 1 and 2 also.