Really weird electric issue

[ANarrowEscape]

Hi all.

I'm having a weird issue with electrics. I'm currently repairing a roof and chimney collar, so haven't been able to stay overnight on the boat for a month. Anyway, everyone I go back to the boat the electric has tripped; there's nothing really left on apart from the emergency pump thing, and a little gas sniffer - that runs on very little current. 

Thing is it never happens when we're staying overnight, only when we're not there?

I have now wired the gas sniffer onto another system I built, which is completely independent.

It's literally like someone is sneaking on-board and turning the switch when we're not there. Which did cross my mind, so I put kitchen roll on the steps of both ends, but was exactly how I left it when I returned. 

Weird, any ideas?

 

Thanks

[nb Innisfree]

Something to do with lack of air movement from people moving around or colder boat inhibiting air movement?

[ANarrowEscape]

2 minutes ago, nb Innisfree said:

Something to do with lack of air movement from people moving around or colder boat inhibiting air movement?

Maybe the cold, but not sure why it would trip the electric. There are no issues when I turn it back on, and have stayed the night (possibly same temperature was it would be without me being there). 

Weird.

[Momac]

Try a different shore power cable.

[TheBiscuits]

Is one of your neighbours unplugging you when you aren't there?

 

 

[ANarrowEscape]

3 minutes ago, MartynG said:

Try a different shore power cable.

Don't have one. This is 12v. Boat has 5 leisure batteries. Mainly runs on solar, or I run engine or generator for a couple of hours - when I'm there.

 

3 minutes ago, TheBiscuits said:

Is one of your neighbours unplugging you when you aren't there?

 

 

There's nothing to unplug. Or I would have thought that. I even setup sheets of kitchen roll on steps, in case someone was seeking in. But that's not it.

Very weird.

 

[nicknorman]

What exactly do you mean by “the electric has tripped”. I think we though you meant a shore power RCD, but it seems you are talking about the 12v system. So exactly what device / switch etc has tripped?

[TheBiscuits]

6 minutes ago, ANarrowEscape said:

There's nothing to unplug.

 

Ah right.  A couple of us assumed this was shorepower tripping.

 

First thing to check is the bilge pump - does it trip the breaker when used manually?  If it's seized, it might.

 

Do you need the gas sniffer running when you are not there?  Try disconnecting it and see if the boat survives a few weeks without tripping the breaker.

 

If it's neither of those things then I'd strongly recommend contacting @Duck-n-Dive to have a rummage - he's near Chorley at the moment but will travel.

 

[ANarrowEscape]

Yeah, the 12v. The system is a bit old to be fair, so doesn't have individual trip switches, so it's the master switch that's always tripped. I've put one of the two things (the 12v gas sniffer) onto a different system, so it only leaves the water pump and the emergency water pump thing near the engine. I'm going to connect them to something else to see if it's that. It's just weird it doesn't do it when I've stayed. Never happens then? 

 

2 minutes ago, TheBiscuits said:

 

Ah right.  A couple of us assumed this was shorepower tripping.

 

First thing to check is the bilge pump - does it trip the breaker when used manually?  If it's seized, it might.

 

Do you need the gas sniffer running when you are not there?  Try disconnecting it and see if the boat survives a few weeks without tripping the breaker.

 

If it's neither of those things then I'd strongly recommend contacting @Duck-n-Dive to have a rummage - he's near Chorley at the moment but will travel.

 

Yeah, I thought the same so have connected the gas sniffer to another system (a small 2 battery system which runs the USBs). 

Duck and Dive is coming to fit a new fuse box when he can, so will see what happens then. 

I've run the bilge (that what it's called) pump on a spare battery and it runs fine. But there's no water in the bay to ever set it off.

I am going to keep the pump on the spare battery to see if it's that, but I don't think it is.

Very strange.

 

[Tony Brooks]

1 minute ago, ANarrowEscape said:

Yeah, the 12v. The system is a bit old to be fair, so doesn't have individual trip switches, so it's the master switch that's always tripped. I've put one of the two things (the 12v gas sniffer) onto a different system, so it only leaves the water pump and the emergency water pump thing near the engine. I'm going to connect them to something else to see if it's that. It's just weird it doesn't do it when I've stayed. Never happens then? 

 

A master switch can't trip. its either on or off BUT a typical red key job will eventually go faulty and appear to urn itself off although the key will still be in the on position. Try a ball of paper under the key or better still fit a decent quality master switch.

[ANarrowEscape]

It's quite stiff, or as stiff as it should be. The key is literally turned. Which worried me even more now, if it doesn't do that when it trips :).

I'm now thinking sneaky CCTV is needed.

 

2 minutes ago, Tony Brooks said:

A master switch can't trip. its either on or off BUT a typical red key job will eventually go faulty and appear to urn itself off although the key will still be in the on position. Try a ball of paper under the key or better still fit a decent quality master switch.

It's quite stiff, or as stiff as it should be. The key is literally turned. Which worried me even more now, if it doesn't do that when it trips :).

I'm now thinking sneaky CCTV is needed

[nicknorman]

Yes are you sure it is “tripping” as opposed to just turning itself off. Some designs of master switch have a spring to open the contacts, and a kind of screw down/ bayonet device that keeps the contacts closed against the spring. So perhaps it is just a mechanical wear issue, over prolonged periods the bayonet type lock is somehow slipping and allowing the spring to open the contacts,

[ANarrowEscape]

Just now, nicknorman said:

Yes are you sure it is “tripping” as opposed to just turning itself off. Some designs of master switch have a spring to open the contacts, and a kind of screw down/ bayonet device that keeps the contacts closed against the spring. So perhaps it is just a mechanical wear issue, over prolonged periods the bayonet type lock is somehow slipping and allowing the spring to open the contacts,

It feels fine when I turn it. Doesn't feel like any issues, and is stiff - definitely enough to keep itself in position. 

The real mystery is it never does it when I stay overnight etc.

I'd say someone is pissing about, but I doubt anyone I'm near would be arsed to do it. Even though they would have to sneak in through locked doors etc. 

Strange. 

I'm going to try a new fusebox, hoping it's that.

[nicknorman]

2 minutes ago, ANarrowEscape said:

It feels fine when I turn it. Doesn't feel like any issues, and is stiff - definitely enough to keep itself in position. 

The real mystery is it never does it when I stay overnight etc.

I'd say someone is pissing about, but I doubt anyone I'm near would be arsed to do it. Even though they would have to sneak in through locked doors etc. 

Strange. 

I'm going to try a new fusebox, hoping it's that.

If it is a normal type of master switch with some sort of key thing to be turned 90degrees or whatever, there is no inbuilt overcurrent detection. Ie it won’t open with some sort of electrical overload. I therefore suggest that replacing the fuse box is pointless. Better to replace the master switch.

 

Maybe you have some ship’s rats that are accidentally operating the keyswitch as they scamper by?

[ANarrowEscape]

Just now, nicknorman said:

If it is a normal type of master switch with some sort of key thing to be turned 90degrees or whatever, there is no inbuilt overcurrent detection. Ie it won’t open with some sort of electrical overload. I therefore suggest that replacing the fuse box is pointless. Better to replace the master switch.

 

Maybe you have some ship’s rats that are accidentally operating the keyswitch as they scamper by?

Yeah, it's as you described. But I think the switch is built in with the box, so would have to replace box with switch. 

CCTV next. 

[Alan de Enfield]

24 minutes ago, ANarrowEscape said:

 ?Yeah, it's as you described. But I think the switch is built in with the box, so would have to replace box with switch. 

CCTV next. 

I think there may be some misunderstanding about 'what you have got'.

 

Can you post some photos of your electrical system including fuse boxes and any switches ?

[ANarrowEscape]

Just now, Alan de Enfield said:

I think there may be some misunderstanding about 'what you have got'.

 

Can you post some photos of your electrical system including fuse boxes and any switches ?

Will do. Going over in next couple of days.

 

[David Mack]

Why are you leaving the master switch on when you leave the boat? I always turn it off when leaving the boat, as well as turning the gas off at the bottle. If you want to leave an automatic bilge pump connected, that can be run through a separate fuse, fed from the battery side of the main switch. Likewise solar to keep the batteries topped up.

Not sure what the point of a gas sniffer is when you are not there. Turning off the gas at the bottle will minimise the chance of gas in the boat anyway, but if gas is detected what is the point if you are miles away?

[Bod]

You have a ghost.

 

Bod.

[nicknorman]

 

22 minutes ago, David Mack said:

Why are you leaving the master switch on when you leave the boat? I always turn it off when leaving the boat, as well as turning the gas off at the bottle. If you want to leave an automatic bilge pump connected, that can be run through a separate fuse, fed from the battery side of the main switch. Likewise solar to keep the batteries topped up.

Not sure what the point of a gas sniffer is when you are not there. Turning off the gas at the bottle will minimise the chance of gas in the boat anyway, but if gas is detected what is the point if you are miles away?

Well it takes all sorts! When we leave the boat for months, we do the same as we do at the house, ie we leave the gas switched on. The standards for gas installations on boats are pretty high, higher than in a house.

 

We also leave the battery master switch on. As we do in the house (well, as in we don’t turn off the main switch in the house). We do have an electronic dc distribution system with a “virtual” master switch that we switch off, but the underlying microprocessors and canbus interconnection system is still powered up, as is the GSM a receiver for remote control of the heating.

 

I know that a lot of people do totally cut off everything on their boats when they leave it, but it doesn’t seem very logical to me.

Edited December 26, 2020 by nicknorman

[ANarrowEscape]

20 minutes ago, David Mack said:

Why are you leaving the master switch on when you leave the boat? I always turn it off when leaving the boat, as well as turning the gas off at the bottle. If you want to leave an automatic bilge pump connected, that can be run through a separate fuse, fed from the battery side of the main switch. Likewise solar to keep the batteries topped up.

Not sure what the point of a gas sniffer is when you are not there. Turning off the gas at the bottle will minimise the chance of gas in the boat anyway, but if gas is detected what is the point if you are miles away?

I just leave it on because that's what was advised previously, and we do have neighbors who have said they would check on it if there are any issues. But like I say, I've now connected that to another system and that hasn't tripped, so I can say it isn't that. I leave the main switch on mainly because of the pump, but I am going to be swapping that onto another battery to eliminate that as well. 

5 minutes ago, Bod said:

You have a ghost.

 

Bod.

Don't. I'm not sure how much an exorcism is, but I'll bet it's costly.

[tehmarks]

 

20 minutes ago, nicknorman said:

 

We also leave the battery master switch on.

As a cruising liveaboard, the master switch goes off every time I leave the boat for longer than 24 hours in winter — but that's to protect the batteries, not because I expect my electrical instalation to suddenly become defective and burst into flames. Spring through autumn, I might not bother as long as I wasn't moored under a canopy of leafy trees.

[haggis]

27 minutes ago, nicknorman said:

 

 

I know that a lot of people do totally cut off everything on their boats when they leave it, but it doesn’t seem very logical to me.

When we were at streethay they once moved our boat into the workshop and when they put it back on its mooring, they didn't turn the master switch off. The result was very flat batteries when we went down some time later. The cause,?  The "level indicators"  for the water tank, the loo tank and the fuel tank were all on. None of them pulled my h current but collectively over a period it was enough. 

Our master switch is always off when we leave the boat to come home.

 

Haggis

[ditchcrawler]

I once had to drive back to Napton from Lowestoft because I suddenly remembered the inverter was still powered up as the main isolator was still on.

[nicknorman]

20 minutes ago, haggis said:

When we were at streethay they once moved our boat into the workshop and when they put it back on its mooring, they didn't turn the master switch off. The result was very flat batteries when we went down some time later. The cause,?  The "level indicators"  for the water tank, the loo tank and the fuel tank were all on. None of them pulled my h current but collectively over a period it was enough. 

Our master switch is always off when we leave the boat to come home.

 

Haggis

When I press the “virtual master switch” button, lots of things get turned off electronically including the level meters. My point really is that there is no fundamental need to turn off the master switch, provided all the consumers are turned off, or at least those that you want to have turned off.