Why can't I turn off my electrics? (photo shown)

[yodave]

Spec: 2 x large-ish batteries (think they might be 125 AH), and an Osculati heavy duty switch. I understand we have slightly larger batteries to cope with the power requirements of the bow thruster.

Pretty sure that I used to be able to switch off my electrics, but now when I turn off the master switch I'm still able to turn on the main cabin lights and other items despite the master switch being off. I even tried turning off what looks to be some sort of fail-safe (it's a plastic red tab - almost visible on the far left of the image attached to the positive terminal of battery number one), but that had no effect.

I'm no expert, however I reckoned that if the master switch was off, then everything beyond the switch should be off. With this in mind, I reasoned that the switch must be faulty ...so I bought a new one (the same switch) and swapped it out. The new one is in the photograph above, and it didn't solve the problem. So I'm stumped. If the master switch is off, surely that should be a barrier to everything else?

Any ideas? Starters for ten?

Thanks in advance for any thoughts right, wrong, half-baked or otherwise.

 

[sailorman]

what are those 2 heat sinks
a power cable goes between that & a battery + 2 small cables from the heat sink to where ??

 

[Talulah]

The big switch may be just for engine starting. The domestics being connected directly to the battery.
Put the big switch in the 'off' positions and see if you can start the engine.

 

[yodave]

sailorman: Sorry, I'm pretty clueless when it comes to electrics so I don't know. Three thick red cables run to the positive terminal of battery two, I say thick because they may be aggregated. What I can do, is check over the weekend, so I'll put this on my list ...thanks!

 

[sailorman]

what are those heat sinks attached to

 

[VicS]

Spec: 2 x large-ish batteries (think they might be 125 AH), and an Osculati heavy duty switch. I understand we have slightly larger batteries to cope with the power requirements of the bow thruster.

Pretty sure that I used to be able to switch off my electrics, but now when I turn off the master switch I'm still able to turn on the main cabin lights and other items despite the master switch being off. I even tried turning off what looks to be some sort of fail-safe (it's a plastic red tab - almost visible on the far left of the image attached to the positive terminal of battery number one), but that had no effect.

I'm no expert, however I reckoned that if the master switch was off, then everything beyond the switch should be off. With this in mind, I reasoned that the switch must be faulty ...so I bought a new one (the same switch) and swapped it out. The new one is in the photograph above, and it didn't solve the problem. So I'm stumped. If the master switch is off, surely that should be a barrier to everything else?

Any ideas? Starters for ten?

Thanks in advance for any thoughts right, wrong, half-baked or otherwise.

I would expect every thing to be off when the main isolator is off, except for connections to chargers and any other items you might want to be "always on"

Difficult to deduce anything from a photo.

I suggest you draw a wiring diagram. The problem will then probably be apparent to you. If not then someone will certainly be able to help

 

[yodave]

Talulah: I didn't try this as the tide was out when I swapped the switch earlier today. The new switch made no difference, so assuming that it works exactly as before, I would not be able to start the engine. So what you're saying is that it could be intentionally wired to leave the domestics on 24/7. I suppose that makes sense in some ways, but it leaves me open to draining the batteries if I forget to turn something less obvious off. I had assumed that turning the electrics off completely was a standard safety routine. I'll double check whether the engine starts with the switch off over the weekend. Thanks for your input!

 

[yodave]

what are those heat sinks attached to

sailorman; My best guess would be that they're related to the bow thruster, as that's the biggest power requirement that we have ...but I simply don't know. Sorry. I will try to check when I'm at the boat over the weekend. Thanks!

 

[yodave]

VicS; Me too. Having read the replies so far, I'm already beginning to think that the former owners wanted the lights, radio etc always on ...and so perhaps it's been wired like that.

A wiring diagram would make sense ...unfortunately I wouldn't know where to start. It's just a bunch of spaghetti to me at the moment. I think what I'll do over the weekend is some diagnostics of what works and what doesn't work when the main switch is off. That seems achievable even to me, and might give me some clues. Thanks for your thoughts.

 

[Spyro]

Sorry to say it but if you can't work it out by following cables and see what goes where then any advice you get here will be pretty useless. one thing I'd say is it doesn't sound like a fault just the way something is connected.

 

[sailorman]

Sorry to say it but if you can't work it out by following cables and see what goes where then any advice you get here will be pretty useless. one thing I'd say is it doesn't sound like a fault just the way something is connected.

i have permanant live`s
vhf
bilge sensor
navtex
micro / radio memory
Aerogen regulator

 

[VicS]

VicS; Me too. Having read the replies so far, I'm already beginning to think that the former owners wanted the lights, radio etc always on ...and so perhaps it's been wired like that.

A wiring diagram would make sense ...unfortunately I wouldn't know where to start. It's just a bunch of spaghetti to me at the moment. I think what I'll do over the weekend is some diagnostics of what works and what doesn't work when the main switch is off. That seems achievable even to me, and might give me some clues. Thanks for your thoughts.

A sheet of paper and a pencil.

Draw a couple of rectangles to represent the batteries, and circles or smaller rectangles to represent other items. Draw on where each bit of spaghetti goes.

 

[BGarner]

In the photo it shows a black lead to the battery switch. Hope this is wrong as they should all be 12V positives on there.
It may be that the previous owner used the black as a feed because he had no red.

Brian

 

[halcyon]

What's the black wire going into the isolator switch ?

Brian

 

[William_H]

If you discover that the cabin lights etc are not meant to be useable with switch off then there may be a problem. As said some devices are usually wired to be on at all times. Typical is a keep alive memory for a music radio. So you get a pos battery supply for the radio via the main switch but you get another pos battery supply for the memory. Now if someone wired these correctly then another person joined the 2 battery positive supplies together you could get you scenario. Likewise with bilge pump clocks and other devices. So try removing fuses or switching off supplies to all those things except the cabin lights. Do the cabin lights still operate with master power off?
Of course the previous owner might have preferred cabin lights available at all times for late night arrivals. Check other things. good luck olewill

 

[OceanSprint]

To the OP

Is there a secondary source of power? Such as a solar panel or wind generator? Killing the batteries won't kill the other source.

 

[ghostlymoron]

To the OP

Is there a secondary source of power? Such as a solar panel or wind generator? Killing the batteries won't kill the other source.

Really? Most installations lead the alternative sources to the battery. Power drawoff is then controlled by an isolation (main switch). Exceptions are as described by ole will. IMO it'sessential to draw a circuit diagram. If you can't do it yourself, you need to get help but it's really not that difficult apart from having to crawl all over your boat - just follow Vics procedure, post up the result and you'll get good advice here.

 

[sarabande]

Can I suggest that VicS' process is the best one.

You are trying to create a circuit diagram, not an "as installed" one. The latter may look like a spagetti meal, but the circuit diagram should be able to resolve where all the power goes from, and which devices it goes to. A circuit diagram fulfills the same function as a London Underground map: it does not represent the actual, geographical, layout, but is a schematic, topographical layout.

It's a fairly significant safety function that you understand the electrics, not necessarily in terms of Ahrs, resistance, ohms and whatever, but in simple terms of where the electricity is generated, how it gets to the batteries, and how it flows from the batteries to the various devices, together with which switches can isolate or divert power flow.

 

[yodave]

Spyro: At least some of the cables disappear behind fixtures and fittings such as the ceiling and other panels, and then there's the jungle of wires behind the switch panel. On the plus side some of the wires do seem to be labelled (in Dutch), so maybe that might make things easier ...as would a second pair of eyes/hands. If I can make this happen, then perhaps I can have a go over the weekend. Thanks for your help.

sailorman: Thanks again for your help. I had previously just assumed that the main switch should kill everything, so perhaps this is just part of getting to know our boat better.

VicS: I think this would be easier if I can get a pair of eyes/hands at each end of the cables, so I'll give it a go when I can make that happen. Thanks again!

BGarner: Yes I noticed that too. The black cable in question goes on to the positive on battery one. As we've had the boat since 2011 and it's worked well, I reckon that maybe there was a shortage of red cable at the time (or perhaps Dutch electricians are prone to throwing a curve ball every now and then). Thank you for taking the time to contribute.

halcyon: The black wire going into the switch comes from the positive of battery one. Not sure why it's black, and with limited knowledge it confused me a bit, but I reasoned that it's been working for two years plus (probably more like a decade), so must be okay. Thanks for your input.

William_H: Thanks for your thoughts. It's becoming obvious that the main switch doesn't necessarily do as I had assumed it would do. Given that's the case, then it could well be that we don't actually have a problem ...just a solution that isn't inline with my understanding. If that's the case, then the former owner's solution must be 'manageable'. I should be able to do some diagnostics over the weekend, to see what works and what doesn't work when the power is off. Thanks.

OceanSprint: We have no secondary source of power. We tend to charge the batteries when the engine is on or when we're plugged into shower power. Good left-field thought, but the power source is definately the batteries. Thanks for taking the time to give me your thoughts.

ghostlymoron: I'm going to give drawing a circuit diagram a go when I can get another (willing) pair of eyes/hands. Thanks for your advice.

sarabande: You're right. My ignorance of the electrics isn't something that I can live with indefinately. It's been a steep learning curve over the last two years, and it seems that I've still got a long way to go. Drawing a circuit diagram is now firmly on my 'to do' list, and with a bit of luck I'll get that done over the coming weekend ...after all it doesn't look like the weather in Scotland is going to be condusive to a leisurely cruise out on the water. Thanks for your help.

 

[malpasman]

Slightly off subject, but the battery connection [on the left / bottom of photo] may require attention as the 2 large cables are connected with the butterfly nut.

The nut appears to have very little thread in contact with the nut [bolt too short]. If this fails you could loose all electrical supply, if it works loose you could have a burn up, an accident waiting to happen.

With regards to the black cable going to the selector switch, if it is a pos supply, put a ring of red tape either end to remind you.

Regards MM