Need some help (dual Battery)

[bgorm6]

my dual battery setup will be the following:
main battery to a projecta 150amp under the hood with 150amp fuse inbetween then cable running to the back of the car to a 175amp anderson plug.
My Question is do i need a fuse inbetween that anderson plug at the back of the car to the isolator in the engine bay ?
thanks in advance

 

[bods]

Personally I would. The fuse or breaker is to protect the wire from causing a fire if it shorts on anything. Any reason you have such a big Anderson plug on the rear? Are you planning on drawing that much power through it?

 

[bgorm6]

cheers for that, got a 120amp battery so i thought i would go with the larger anderson plug

 

[bods]

Fair enough. As long as the cable can handle higher amps than the fuse or breaker is rated for you will be OK. If you have a 120a/h battery that's a different rating to the 175 amp Anderson plug. Your alternator probably only has around 20-30 amp spare after charging your main battery, running the accessories, etc.

If you try and draw that much out of your aux battery it may end up killing it very quickly if it is anything but an agm battery...

 

[bods]

Grrrr

 

[bgorm6]

the cable is 50mm2 which i think equals to 0b&s as its fire cable. the anderson plug just connects to the battery so i can removed the battery when needed

 

[bods]

Ah OK, I get you now. If that's the case, you will need another fuse either on the lead between the aux battery and the Anderson plug or on the isolator side of the Anderson plug mounted to the car as close as possible to the aux battery. That's just to stop the aux battery starting a fire if the wire gets damaged.