BEP Horizontal Battery Distribution Cluster with VSR

VicS said:
Therefore there's no point in reconfiguring the switch cluster either.
Click to expand...

I'd disagree. The point of reconfiguring the cluster is so that you can isolate the start battery and start the engine from the domestic battery instead. The most likely scenario for this is if the start battery has become discharged - not necessarily due to a battery fault condition.
 
pvb said:
I'd disagree. The point of reconfiguring the cluster is so that you can isolate the start battery and start the engine from the domestic battery instead. The most likely scenario for this is if the start battery has become discharged - not necessarily due to a battery fault condition.
Click to expand...

The point of reconfiguring the switch cluster is so that a defective battery can easily be isolated without tools or even accessing the battery compartment.

You can use the paralleling switch as originally intended in the case of a starter battery that is merely discharged too deeply to start the engine on its own.
 
VicS said:
The point of reconfiguring the switch cluster is so that a defective battery can easily be isolated without tools or even accessing the battery compartment.

You can use the paralleling switch as originally intended in the case of a starter battery that is merely discharged too deeply to start the engine on its own.
Click to expand...

No, if you use the original parallel switch, it connects a deeply discharged battery to a good battery, resulting in current draining out of the good battery, thus reducing the available power for the starter motor. That's the real reason for reconfiguring the switch cluster.
 
pvb said:
No, if you use the original parallel switch, it connects a deeply discharged battery to a good battery, resulting in current draining out of the good battery, thus reducing the available power for the starter motor. That's the real reason for reconfiguring the switch cluster.
Click to expand...

Very true. Depending on the depth of discharge of the batteries, you might not be able to start the engine.
 
The switch arrangement isn't just there for a flat engine battery, it covers a dead domestic battery too.

You're just sailing into a busy harbour in the dark, lots of big ships, lots of leisure boats etc. Something goes wrong with the domestic battery and you lose all power. No nav instruments, no sounder, no VHF, no nav lights. No problem, isolate the domestic battery, turn on the emergency switch, everything powers back up. Wire the BEP way, if you turn the emergency switch on it'll drain the engine battery, so everything goes off again, plus, you can't start the engine.

All this wittering about the VSR still paralleling the batteries is a bit over the top. For a start, you have to have a charging source running to close the VSR. Even then, so what ? Some charge current might be going to the dead battery, do we care, it's an emergency. If current drain via the VSR was excessive, it would open again, if ity got really silly, the fuse will blow.

If you're really anal or an internet forum armchair expert, fit a switch in the VSR neg or use a double pole emergency switch or rig some relays up etc etc etc
 
Pete7 said:
You get one in the box if you buy a set of BEP switches, but if not the picture Gixer posted is pretty good.

Connections A-B are the house bank switch. C-D are the engine start switch and the middle unlabelled switch the combiner for when the engine won't start and you have flattened the battery. Or, if its a really simple design and there is no charging other than the alternator then close the middle switch so the alternator charges both engine and house bank, not forgetting to open the switch when you stop so you don't drain the engine start battery using the house electrics.

Pete
Click to expand...
thank you
 
One more question that has been answered on another thread of mine but I just want to double check here.

Between my engine and two batteries on the -ve (negative) side is another isolator, one of the cheap red key ones. Can I remove this and replace it with a bus bar with no ill effects to safety or the anodes, etc.
I don't know why the previous owner put a isolator in the negative as well as the 1/2/both switch which is why i'm nervous??
 
Gixer said:
One more question that has been answered on another thread of mine but I just want to double check here.

Between my engine and two batteries on the -ve (negative) side is another isolator, one of the cheap red key ones. Can I remove this and replace it with a bus bar with no ill effects to safety or the anodes, etc.
I don't know why the previous owner put a isolator in the negative as well as the 1/2/both switch which is why i'm nervous??
Click to expand...

You don't need an isolator in the negative cable.
 
Gixer said:
One more question that has been answered on another thread of mine but I just want to double check here.

Between my engine and two batteries on the -ve (negative) side is another isolator, one of the cheap red key ones. Can I remove this and replace it with a bus bar with no ill effects to safety or the anodes, etc.
I don't know why the previous owner put a isolator in the negative as well as the 1/2/both switch which is why i'm nervous??
Click to expand...

A recent discussion revealed that some boat builders ( Beneteau ??) fit them as a matter of course. Someone was going to try to find out why but I have not seen any feed back. but I may have missed it.

VP show negative isolators in wiring diagrams their engines which have Isolated electrical systems ( ie dont use the engine block as a common negative connection)
Dont know why.... maybe something to do with protecting an uninsulated sail drive ????

If you know its just something of poor quality a PO fitted and you dont want it remove it,
 
VicS said:
VP show negative isolators in wiring diagrams their engines which have Isolated electrical systems ( ie dont use the engine block as a common negative connection)
Dont know why.... maybe something to do with protecting an uninsulated sail drive ????
Click to expand...

Do Volvo supply the negative isolator with the engine wiring ?

Do they specify it must be fitted ?

How will it "protecting an uninsulated sail drive " ? Particularly as VP saildrives are isolated.
 
PaulRainbow said:
Do Volvo supply the negative isolator with the engine wiring ?

Do they specify it must be fitted ?

How will it "protecting an uninsulated sail drive " ? Particularly as VP saildrives are isolated.
Click to expand...

No idea to all three questions. I only stated what I see in the schematics in the manuals.
You are the one who claims to be some sort of electrician. I thought you might be able to shed some light on the matter

VP sail drives have not always been isolated !
The isolation was introduced with the B versions of the MD 2010 , 2020 etc series of engines.
The sail drives are not isolated from earlier engines.
They are also not isolated from the MD22 series engines .
 
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VicS said:
No idea to all three questions. I only stated what I see in the schematics in the manuals.
You are the one who claims to be some sort of electrician. I thought you might be able to shed some light on the matter
Click to expand...

That's the drawback reading manuals and schematics with no real World experience or knowledge of the subject matter, you don't actually know the real World answers.

Sitting at home in your retirement from a totally unconnected profession (chemist, wasn't it ?) and Googling manuals, schematics, instruction manuals etc and posting replies is all well and good, it obviously passes some time for you and when you inform someone that "the green wire goes from A to B, i'm sure that's very helpful and the poster appreciates it. All good stuff. Then you get a bit carried away and start wanting to redesign accepted standards and practices and start arguments about areas you have no real knowledge or experience of, there have been several examples recently.

I shed light on the subject of the negative isolators in the other thread, some of which was apparently confirmed by a Benneteau importer. One poster said:

Benneteau and Jeanneau have been fitting negative isolators for decades. That doesn't mean they are fitted for some mysterious technical reason that only they are aware of, they fit them because they choose to, same reason as they choose to fit anything else. If they were there because of some technical requirement for a particular engine or transmission every manufacturer would fit them. If they were there because of regulatory requirements, every manufacturer would fit them.

Benneteau and Jeanneau fit them to boats fitted with various makes and models of engines, shaft drives, insulated saildrive and non-insulated saildrives. Other manufacturers fit the same engines and transmission and don't fit negative isolators.

VP sail drives have not always been isolated !
The isolation was introduced with the B versions of the MD 2010 , 2020 etc series of engines.
The sail drives are not isolated from earlier engines.
They are also not isolated from the MD22 series engines .
Click to expand...

I'm perfectly aware of when VP introduced saildrive isolation, but that has no relevance to the fitting of negative isolators by Benneteau and Jeanneau (see above), that's a nonsense theory that you threw into the thread.
 
Gixer said:
Humm, if a busbar is rated for a max ampage of 210 Could this cause a problem on a cable with a 225amp fuse?
VTE 210A 4 Point Negative Distribution Block/Busbar
Click to expand...

That's a max continuous rating, which i don't think you'll be exceeding :)

If you connect the engine negative to the same stud as the engine battery the only loads that run through the busbar are domestic loads. Only way the average sailing yacht will get over 210a is if there is a short, in which case the fuse will blow before the busbar melts.

So PVB is correct (y)
 
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I thought it might the the continuous current rather than a peak.

I've pretty much got my entire boat wiring mocked up in my garage, can’t wait to get it all fitted!

Thanks again guys.
 
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