Oh Dear ... pal of mine connected battery wrong way round !!

Refueler

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Pal of mine just put a 180 A/hr battery in his boat replacing 2 smaller that had come to end of life ...

Previous owners had used any wire they could .. and various are coloured wrong ...

He connected battery ... switched on .... BIG FLASH ... loads of smoke ...

He connected it ass about ... and being fully charged decided to fry the relays / VHF / most of his other electronics etc. Even caused the smaller starter battery to fail ... obviously buckled plates inside !

He was very lucky it was not more and injury..
 

B27

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That's embarrassing!
Some equipment has an internal fuse and a diode to blow the fuse, so some things might be fixable,

On cars, reversing the battery classically kills the alternator diodes.
 

pmagowan

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Yep. To be honest if you are accepting poor and unusual wiring practices in your boat then your risk aversion is set too low. Basically your friend has been given an opportunity to replace his wiring in a safe way. He obviously should have done this previously but sometimes people need a bit of persuasion. Nobody badly hurt it could have been much worse at any time for anyone staying on the boat.
 

Refueler

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Yep. To be honest if you are accepting poor and unusual wiring practices in your boat then your risk aversion is set too low. Basically your friend has been given an opportunity to replace his wiring in a safe way. He obviously should have done this previously but sometimes people need a bit of persuasion. Nobody badly hurt it could have been much worse at any time for anyone staying on the boat.

He was on the boat at the time ... it was when he switched ON battery power ....
 

penberth3

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Yep. To be honest if you are accepting poor and unusual wiring practices in your boat then your risk aversion is set too low. Basically your friend has been given an opportunity to replace his wiring in a safe way. He obviously should have done this previously but sometimes people need a bit of persuasion. Nobody badly hurt it could have been much worse at any time for anyone staying on the boat.

With hindsight, knowing the wiring was bodged, labelling or coloured tape might have helped.
 

davidmh

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The tapered post type of battery means that cannot connect up the wrong way round, don't know if the other types do. where I have extra leads onto the battery I tiewrap those to the main + or- connection leads
david mh
 

Refueler

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The tapered post type of battery means that cannot connect up the wrong way round, don't know if the other types do. where I have extra leads onto the battery I tiewrap those to the main + or- connection leads
david mh

mmmmm I remember tapered posts of different size - but TBH - all batterys I have had over quite a few years are straight posts or nut / bolt L form ... easy to get wrong.

Something that I find annoying with batterys - the + and - symbols are not so easy to see in the half light of a battery box / locker ... manufacturers cast a silly + / - into the case top .... that is easily masked by grime.
I can remember batterys that had a RED and Black ring around the base of posts ...

But anyway - the problem my mate Uldis had ... was not the battery - it was the wiring not being identified by colour properly.
 

Refueler

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Even without fuses, isn't much modern electronic equipment proof against reverse polarity?

Yes - most are ..... we can only hope that gear can be recovered from it.

But imagine here .... a full charged 180 A/hr battery connected into system that has a depleted 90 A/hr battery .... connected wrong and switch on ... the discharge that now hits the system ....
 

penberth3

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mmmmm I remember tapered posts of different size - but TBH - all batterys I have had over quite a few years are straight posts or nut / bolt L form ... easy to get wrong.

......I can remember batterys that had a RED and Black ring around the base of posts ...

Easy enough to put a bit of red paint round the Positive post.

Tapered posts - it is possible to get the connections wrong, with a bit of persuasion, I've seen it done!
 

William_H

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Yes - most are ..... we can only hope that gear can be recovered from it.

But imagine here .... a full charged 180 A/hr battery connected into system that has a depleted 90 A/hr battery .... connected wrong and switch on ... the discharge that now hits the system ....
Yes if the 2 batteries were connected together one the wrong way round then you get a 24 volt battery with a dead (High current) short. Much smoke posibly destroyed batteries. I am guessing his wiring was not so heavy or long that current was somewhat limited. ol'will
 
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