12V battery supply has failed - ideas?

[Airlane1979]

First trip away from mains hookup in a long time and the battery circuit to power sockets has failed. Lights are still okay. Fuses seem okay too. Any ideas for troubleshooting?

[nicknorman]

Do you mean the supply to the mains / 240v sockets? If so these will only work away from shore power if you have an inverter or Combi. If you do have one, check it is switched on and if it is an inverter, normally there is some kind of switching arrangement to select between shore power and inverter power. So you may need to operate this switching mechanism (sometimes as simple as moving a plug between 2 sockets).

 

If you mean 12v sockets, there will be a fuse or breaker to power these sockets, check if it has blown or tripped.

[Dog]

 Trouble shooting?

The person who wired this lot up needs bloody shooting, what a mess.

[MtB]

16 hours ago, nicknorman said:

If you mean 12v sockets, there will be a fuse or breaker to power these sockets, check if it has blown or tripped.

 

 

Given the thread title, I thought the OP meant the 12Vdc sockets.

 

 

 

6 hours ago, Dog said:

 Trouble shooting?

The person who wired this lot up needs bloody shooting, what a mess.

 

 

The photo looks a lot tidier and easy to follow than most boat wiring installations I see. Having it all on show and accessible like that makes fault-tracing infinitely easier. 

 

 

 

 

[MtB]

 

 

16 hours ago, Airlane1979 said:

First trip away from mains hookup in a long time and the battery circuit to power sockets has failed. Lights are still okay. Fuses seem okay too. Any ideas for troubleshooting?

 

 

Without wishing to sound trite, yes, buy a multimeter.

 

Set it to 20Vdc and starting at the battery, use it to trace the voltage at various points along the circuit/wiring from the battery to the dead socket until you find where the voltage drops from 12Vdc to 0Vdc, and there's your fault. 

 

 

Edited June 3, 2022 by MtB
Clarify.

[Tony Brooks]

18 minutes ago, MtB said:

Given the thread title, I thought the OP meant the 12Vdc sockets.

 

 

I can't be sure of that as the OP has, so far, failed to provide further information. They might even think that with no shoreline connected the mains sockets will provide 12V or maybe that any USB  outlet in a mains socket is provides 12V from the battery. Personally I await the reply to Nick's answer.

[Eeyore]

21 hours since the OP joined the forum, and 21 hours since they were last "seen" on the forum. Perhaps we need a software tweak so that we at least know if an OP has read the replies?

[Richard10002]

36 minutes ago, Eeyore said:

21 hours since the OP joined the forum, and 21 hours since they were last "seen" on the forum. Perhaps we need a software tweak so that we at least know if an OP has read the replies?

and what if they hadn't read the replies?

 

I think we often see people who have just joined the forum check back a week or so later, and cant believe the speed with which they got a response. Entirely possible that the OP has decided to give it a week, then check back to see if anyone has answered.

[Tonka]

47 minutes ago, Richard10002 said:

and what if they hadn't read the replies?

 

I think we often see people who have just joined the forum check back a week or so later, and cant believe the speed with which they got a response. Entirely possible that the OP has decided to give it a week, then check back to see if anyone has answered.

Perhaps they have electrocuted themselves 

[Guest]

6 hours ago, MtB said:

 

 

Given the thread title, I thought the OP meant the 12Vdc sockets.

 

 

 

 

 

The photo looks a lot tidier and easy to follow than most boat wiring installations I see. Having it all on show and accessible like that makes fault-tracing infinitely easier. 

 

 

 

 

 

Untidy 12V is one thing but untidy 240v with exposed terminal screws on the breakers is entirely another.

 

As a minimum that bit should be ripped out and a proper consumer unit to enclose the connections fitted. They are not that expensive.

 

That looks to me like a fatality waiting to happen.

[Alan de Enfield]

Just now, The Happy Nomad said:

 

Untidy 12V is one thing but untidy 240v with exposed terminal screws on the breakers is entirely another.

 

As a minimum that bit should be ripped out and a proper consumer unit to enclose the connections fitted. They are not that expensive.

 

That looks to me like a fatality waiting to happen.

 

 

Presumably a DIY fit-out and, not done by an electrician. Anybody with an ounce of electrical knowledge would not do that.

 

Very dangerous

[StephenA]

8 minutes ago, The Happy Nomad said:

 

Untidy 12V is one thing but untidy 240v with exposed terminal screws on the breakers is entirely another.

 

As a minimum that bit should be ripped out and a proper consumer unit to enclose the connections fitted. They are not that expensive.

 

That looks to me like a fatality waiting to happen.

 

Are those breakers at 240V? most of them seem to be connected to relays with titles that suggest they are only 12V

[Guest]

6 minutes ago, StephenA said:

 

Are those breakers at 240V? most of them seem to be connected to relays with titles that suggest they are only 12V

 

Looking again yes I can see that. Its difficult to see on a phone.

 

But they deffo look like 240v breakers to me, which in turn then raises the issue of 12v being used with 240V devices.

 

Perhaps the OP can clarify.

[Tony Brooks]

6 minutes ago, The Happy Nomad said:

 

Looking again yes I can see that. Its difficult to see on a phone.

 

But they deffo look like 240v breakers to me, which in turn then raises the issue of 12v being used with 240V devices.

 

Perhaps the OP can clarify.

 

Not  a problem voltage wise, but its the difference between AC & DC. AC self quenches sparks on breaking while DC keeps the arc going far longer. I would suggest if the breakers are duel or DC rated they should be fine on 12V DC but oof 240 V AC they are likely to fail more often than the proper ones and may weld their contact together so refuse to break upon a short circuit.

[Alan de Enfield]

You may well be correct - once enlarged and follow the wiring it does look like 12v DC

 

What is a 'boiler relay' and a 'sludge gulper relay' and a 'water dump relay' ?

 

 

 

 

Edited June 3, 2022 by Alan de Enfield

[Guest]

9 minutes ago, Tony Brooks said:

 

Not  a problem voltage wise, but its the difference between AC & DC. AC self quenches sparks on breaking while DC keeps the arc going far longer. I would suggest if the breakers are duel or DC rated they should be fine on 12V DC but oof 240 V AC they are likely to fail more often than the proper ones and may weld their contact together so refuse to break upon a short circuit.

 

Quite a bizarre way to do things given proper 12v breaker panels can be had for 30 quid.

[Airlane1979]

I found the fault: a blown fuse in a box hidden away. My fault for working on the inverter without turning off the power. Thanks to all for your suggestions which will help in the future.

[Tony Brooks]

8 minutes ago, Airlane1979 said:

I found the fault: a blown fuse in a box hidden away. My fault for working on the inverter without turning off the power. Thanks to all for your suggestions which will help in the future.

 

Many thanks for the feedback and welcome to the world of undocumented boating.

[MtB]

27 minutes ago, Airlane1979 said:

I found the fault: a blown fuse in a box hidden away. My fault for working on the inverter without turning off the power. Thanks to all for your suggestions which will help in the future.

 

 

So can you enlighten us as to what a "sludge gulper" is please?!! 

 

 

[Alan de Enfield]

7 minutes ago, MtB said:

 

 

So can you enlighten us as to what a "sludge gulper" is please?!! 

 

 

 

 

In the 'outside world' a sludge gulper is used for emptying septic tanks.

Wonder if it is similar on a boat ?

[jonathanA]

On 03/06/2022 at 17:18, Airlane1979 said:

I found the fault: a blown fuse in a box hidden away. My fault for working on the inverter without turning off the power. Thanks to all for your suggestions which will help in the future.

It me or is that somewhat mysterious? What hidden box  ? Working on inverter?  Do you mean you had the cover off and were delving into its interior or you had the inverter on and mains from a shoreline at the same time ? If the latter how did a fuse blow and what was the fuse protecting?

 

Sorry all a bit weird to me...

 

It does look an unusual set up  seemds odd to have a 6 way switchboard with circuit breakers/fuses (with only 3 in use?) feeding a row of mains mcbs seemingly feeding a row of relays for services that would not usually have a relay on most conventional boats.... 

[Airlane1979]

There was a hidden inline fuse, not really a box. I was posting on behalf of a friend whose boat it is and he seems to have it sorted now.

[ditchcrawler]

On 03/06/2022 at 16:32, The Happy Nomad said:

 

But they deffo look like 240v breakers to me, which in turn then raises the issue of 12v being used with 240V devices.

 

Even so its a BSS failure

Edited June 5, 2022 by ditchcrawler
Spilling

[Tracy D'arth]

Schneider / Merlin Gerin  MCBs are approved for DC use. Extensively used in telephone exchange equipment on 48v DC.  Used thousands of them, very reliable.

[nicknorman]

1 hour ago, ditchcrawler said:

Even so its a BSS failure

Which para of the BSS are you thinking of?