How to Wire Up a Sure Power 120 Amp Two Battery Isolator

Updated 06/22/2020 | Published 12/14/2014

Question:

how do I wire it up to a 2002 Chevy Express Van so I can use the second battery to run my audio

asked by: Jack

Expert Reply:

Battery isolator # DW08771 will have connection posts for each battery and for an alternator. The main battery will connect to position one and the alternator to the A post. The second battery will attach to the 2 via a circuit breaker that is rated appropriately for the battery. Output from the second battery positive post will then go to the items you want to power. I have included a picture that should help.

If you do not have a group 1 alternator then the E post will not be used. The alternator needs to have a max output of 120 amps to use this isolator.

expert reply by: Michael H

click to enlarge

Harry B.

6/17/2020

Hello - I have a sure power 1202. I am experiencing pain! main battery (and output from post 1 isolator) is 6v. Auxiliary battery (and output from post 2 isolator) is 12v+ ... system is sourced from alternator and shore power via converter (new - output is 12v+). Q: I should be getting 12v+ from post 1 of isolator??? correct? I believe the isolator is faulty? can you help? much thx

Chris R.

6/22/2020

You should indeed be getting 12V from that post as well. It could be a bad isolator but I would just make absolute sure that all the wires are securely connected. It also might not be a bad idea to contact Sure Power directly as well.