Thread: battery isolater getting hot

If you're looking for a replacement, look at the the Traxide Tronics one ( made by Drivesafe on this site )

Around $100 and seems to work as well as the more expensive ones.

Originally Posted by Pavo

Crump, I've got a Sure Power Seperator Model 1314. I assume it's the same as yours.

Years ago, it failed on me. Both batteries were completely drained.

The original unit did get hot - exactly as you describe. I don't think the current one I have gets hot at all - and has been fine for about 3 years.

Have you got a multi-meter? Test that it works as it should - if you have the original instructions it will tell you how to test it. If you don't have the original insturctions, they are definitely on the SurePower website (www.surepower.com).

I tested mine by connecting it all up, then measuring the voltage of both batteries. They should be seperated at this point. Turn on the headlights, and check that the voltage of the main battery has dropped a little. The aux should not have dropped. Then start the car. Once the alternator puts out over 13 odd volts (can't remember the exact figure the SurePower seperator parallels them at), it will parallel the batteries. Test the voltage again of both batteries - they should be higher and indicate that charging is occuring.

When you stop the car, if you leave the headlights on, you should hear the seperator click and disconnect the batteries.

Not sure if my description is clear (never was good at explaining stuff).

Let me know if you want more details etc or if you want me to check if mine gets hot etc.

Pete

When testing a voltage sensitive mechanical isolator check for continuity between positive poles on both batts. Most of these type isolators close the circuit when they sense 13.5 volts (alternator active) and open the circuit when they sense 12.5 volts, this 12.5 voltage means with a healthy battery they dont isolate the instant the engine shuts down.
Your problem seems to indicate either a collapsed cell in the aux. battery or a short. If the isolator is not working it should still not heat up excessively
unless it has siezed (highly unlikely) or drawing beyond it's rating.
The earth on the isolator, while causing it to malfunction should not cause it to heat up.

I have a Surepower 1314 and the big black flat square piece does get fairly warm, and I've had it like that for about 5 years now

So it may well be normal for you....

Well, I just got back from a fishing trip, ran the fridge and a flouro at night as well as the shower pump, off the auxillary for three days and its all hunky dory, but the isolator still gets too hot to hold your finger on for any length of time after driving for any distance, maybe its normal, but I think I'll be talking to drivesafe regardless.