replacement isolator switch

[TaffyRon]

http://www.screwfix.com/p/ip65-isolator-switch-63a/12556#product_additional_details_container

 

the above link shows a selection of isolator switches, which one would be ok for my 12v system with charging up to 100amp with 500amp battery bank?

 

its to replace the one ive got thats packed up.

 

they are 440 volt? So how will they work in 12 volt system?

[jonathanA]

simple answer - they wont

 

These are AC mains electrical items and just aren't capable of carrying the DC currents you require.

 

at a very basic level you'd never get the battery type cables into the connections on these units.

 

you need to look for a proper battery isolator for automotive or marine applications.

 

something like this on fleabay

 

http://www.ebay.co.uk/itm/HEAVY-DUTY-BATTERY-CUT-OFF-ON-ISOLATOR-SWITCH-MARINE-BOAT-MAX-300AMP-12V-24V-48V-/181430401722?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2a3e183aba

Edited October 16, 2014 by jonathanA

[TaffyRon]

Righto, got ya, cheers

[TaffyRon]

http://www.norfolkmarine.co.uk/shop-online/blue-battery-onoff-isolator-switch-p-18280.html

 

this is the exact one I need, its in norfolk though, anywhere on the llangollen?

Edited October 16, 2014 by TaffyRon

[by'eck]

DC switches/breakers need to cope with greater arcing than AC ones so you really need to buy one dedicated to switching high DC currents. Below is example that is suitable for most marine battery isolator applications with a continuous current rating of 275 amps. Available from most good chandelries or anyone with an E C Smith account.

 

[TaffyRon]

The one in my last link will be a straight swap

[jonathanA]

I'd have thought Kings lock chandlery at Middlewich would have had something along those lines. doubtless other purveyors of overpriced marine goods are available...

[blackrose]

DC switches/breakers need to cope with greater arcing than AC ones so you really need to buy one dedicated to switching high DC currents. Below is example that is suitable for most marine battery isolator applications with a continuous current rating of 275 amps. Available from most good chandelries or anyone with an E C Smith account.

 

I think that's a BEP isolator, which is a Kiwi offering. I've got a set of three - for start, domestics and one in the middle to parallel both banks in case the start battery fails to start the engine. Good design.

[by'eck]

I think that's a BEP isolator, which is a Kiwi offering. I've got a set of three - for start, domestics and one in the middle to parallel both banks in case the start battery fails to start the engine. Good design.

 

Yes BEP although didn't know they were made in NZ. Rotary switching action on contacts allows self cleaning. Although probably not unique this is better than the cheap ones that just push contacts together.