Thread: Redarc no longer isolating

Originally Posted by Ricey

Has anyone else had troubles with their Redarc? Mine has ceased too isolate the main battery, & I'm at a loss as to why. It was installed less than a year ago & I've just had to replace the starter battery. Where should I start, or can someone recommend a auto electrician around the Parramatta area?

How expensive are they to start with? If not too much, it might cost more for an auto elec to fix than to bin it and fit drivesafe's one.

Hi Ricey, try sending an E-mail to Redarc, there not a bad company to deal with so try them and see what they have to say.

Failing that, as B92 8NW posted.

Cheers.

Hi Lads
Mines done the opersite and won't conect the batterys any more without using the manual wire
I rang them and they will look at it for $65 and maybe replace it its only 2 years old

Thanks Drivesafe, I've been to the website & have found contact info removed with a big "GONE FISHING" sign - haha!!! Reading his reasons why I can totally understand, but would never do it myself while running a business! I'll try & get it to a auto sparkie & go from there. If need be, I'll be ordering a SC40 or SC80.
Hey Joel, either way, I'll need a sparky for the job, I need a reliable & clean job done not a Ricey jobby which shorts everything out & starts fires!

Hey Ricey, did it start happening at around the same time as you replaced the starter battery?

AFAIK, the Redarc was altered so that the disconnect voltage was lower because some cars were getting into situations where the Redarc would clunk in, the voltage would drop from the pull from a discharged 2nd battery and then cause the redarc to isolate again. And so the cycle would go on with the clunking in and out.

Anyway, Redarc dropped the isolation voltage to prevent this happening. As I understand it, the D2 has a relatively high charging voltage and the new battery probably also holds onto a higher voltage compared to your old dead one, and I just wonder if its a combination of a new battery and the Redarc with the lowered isolating voltage that is doing this. It's normal for it to take some time to isolate anyway as the battery voltage drops after the car is turned off.

Have you tried disconnecting it from the starter battery to see if this causes it to isolate?

After reading the redarc website, it seems that a test of some kind using a voltmeter during the test should tell if it is working or not. The fact that the led stays on isn't a sign of failure either. It could be that the old main battery just died of natural causes (so to speak). Try spooling the winch in and out a few times whilst watching the voltage drop with a multimeter. At the other end run your fridge, and when you hit 12.5v at the front, it should click off.
If it doesn't, undo it, clean the main and ground connections and try again.
Like all equipment, if the ground isn't up to scratch, it causes electronics to behave weirdly.

Hey Simon, I believe it started happening after being submerged in a dam although the unit shouldn't have got wet considering where it's located. It will though isolate a short while after pulling the fuse leading to the starter battery. Apart from pulling the fuse it stays connected when dropping at or below 12.4v keeping parity between the batteries. Langy, you mentioned about the wiring from the redarc to the 2nd battery being less than adequate the other night , perhaps I should start from there & fit a reasonable gauge?

All is good after the tests, I've got isolation happening once the volts drop below 12.3(ish) on the main. Simons reasoning & Langys tests have resolved my concerns. Thanks Guys!