12 volt supply problem

[Bartdog]

Wonder if anyone can assist in this one. I've got a 2002 heritage cruiser, which has both 12 volt & 230 volt electrics. This last weekend in a bid to conserve battery consumption I back fed 12 volts dc from an external power supply unit, on to the 12 volt +ve & -ve rail of the fuse board. I've done this many times on my previous boat with no problem, it feeds the boat 12 volt electrics & charges the battery, when in a marina.

However on this latest boat, when I disconnected the external 12 volt supply I was left with no battery voltage on the fuse board 12 volt rails. I've check all batteries starter & leisure & the battery voltages are fine, it's just that no voltage is getting from the battery's to the fuse board. Interestingly the fridge works fine as this is fed (via a fuse) directly from the leisure batteries, indicating supplies are healthy. Just wondered if I'm missing something obvious with this latest boat, is there a cut out / relay etc inline with the batteries that I've missed? Any pointers appreciated>>

Ps it's a 2002 heritage cruiser>>

Pps yes - both battery isolators so were on>>

[The Bagdad Boatman (waits)]

somwhere you will have a trip switch or rcb keep looking.

[Keith M]

May be a fuse between the batteries and the 12-volt bus bars of the fuse board

 

 

Keith

[by'eck]

Highly likely your backfeeding was through a relatively low current fuse or breaker fitted to protect the feed from batteries to your distribution board.

 

Although you have learnt the hard way, such practice is very inadvisable. Any charging to the batteries should be through a dedicated and generally fused feed.

[sassan]

Sounds like you've blown either a fuse or some wiring between battery and fuse box.

 

You're going to have to trace the route, checking with a voltmeter at each connection.

 

In future, if you're charging batteries in this way, do it directly to the batteries. Also, beware of batteries overheating!

[Bartdog]

Thanks to all, yes it's going to be a case of tracing back, as noted it's got to be a trip or reset between the fuse board rail & batteries - will report back>>

[ditchcrawler]

Wonder if anyone can assist in this one. I've got a 2002 heritage cruiser, which has both 12 volt & 230 volt electrics. This last weekend in a bid to conserve battery consumption I back fed 12 volts dc from an external power supply unit, on to the 12 volt +ve & -ve rail of the fuse board. I've done this many times on my previous boat with no problem, it feeds the boat 12 volt electrics & charges the battery, when in a marina.

However on this latest boat, when I disconnected the external 12 volt supply I was left with no battery voltage on the fuse board 12 volt rails. I've check all batteries starter & leisure & the battery voltages are fine, it's just that no voltage is getting from the battery's to the fuse board. Interestingly the fridge works fine as this is fed (via a fuse) directly from the leisure batteries, indicating supplies are healthy. Just wondered if I'm missing something obvious with this latest boat, is there a cut out / relay etc inline with the batteries that I've missed? Any pointers appreciated>>

Ps it's a 2002 heritage cruiser>>

Pps yes - both battery isolators so were on>>

Did you get a wiring diagram with it, I thought that was a requirement of the RCD certification?

[Bartdog]

I got what i thought was the full documentation / manual, but the heritage manual refers only to one of the appendicies which details the individual fuse circuits & not the feed to the fuseboard.

Ive already been on to heritage for electrical support, but still awaiting assistance. i'll get on to them again & ask for the full diagram

Bartdog>>

[Bartdog]

Problem solved, many thanks to all & Heritage, problem was the leisure battery's isolation switch not quite making. Gave it a birthday ( & the starter battery switch ) & all is well>>

Bartdog>>