Temperature Sensor for External Regulator - Ample V2

[CaptTom]

I have a "vintage" external alternator regulator made by Ample Power (since out of business.) It's listed as model "V2."

It's begun failing with an error code (flashing light) indicating "over temperature" even when the batteries, engines and alternators are cold. There is a battery temperature sensor connected to the regulator.

I can't find any specs or part number for the sensor. It looks just like a normal battery cable connector with two small wires coming out of it.

Any idea what I should be looking for?

[Bycrick]

Unless someone here knows what the sensor really is, you might be relegated to cutting away the metal terminal and trying to trim away the potting compound to hopefully see the number left on the device. There are only a couple of different types of commonly used temperature: the resistive types where the resistance varies with temperature, and the temp-sensitive transistor type. They’re both cheap and readily available, but not interchangeable. If the old one is really broken, measuring it won’t help. Good luck.

[CaptTom]

Originally Posted by Bycrick

Unless someone here knows what the sensor really is, you might be relegated to cutting away the metal terminal and trying to trim away the potting compound to hopefully see the number left on the device.

Thanks, I wonder if the numbers would be even visible after extracting it from the potting material. Worse, it's a destructive test. If I fail I'm really stuck.

As of right now, I've been unable to confirm that sensor is even the problem. The manual talks about ensuring the wires are tightly twisted. That wasn't done before, so I tried it. Unfortunately the problem has been intermittent, and I've been unable to duplicate it at the dock with fully charged batteries.

Each time it happened, the bank was down a bit and needed a good charging current. So I have at least one more test to run. If I can't duplicate it with a lower state of charge, I'd really like a spare temperature sensor to pop in when/if it happens again.

According to the manual, if it did happen again underway I could pull the sensor wires off the terminal and it'll default to assuming something like 77 degrees F. That should be OK for a while, but having a spare handy would be preferable.

[Bycrick]

Many years ago, I had the original, manual Ample Power system. One of the pieces quit, and APC had just gone into their first bankruptcy, abandoning all the products. I was so irritated that I took a Dremel tool, and spent many hours to trim away all the potting compound. It was easy to identify the components, which allowed me to buy them all for under $10. After that, I avoided APC equipment.

I don’t have BATTERY temp sensors on my alternator system anymore because the ambient temperature where I am doesn’t vary by much. The solar and shore power systems do, and I use them to make sure the batteries aren’t really getting hot. Yes, I know I could "optimize" the charging from the alternator by trimming the voltage set points, but the difference between 75 and 90 F isn’t enough to make it worthwhile.

[stormalong]

I have the same voltage regulator. It can be run without the sensor. In fact the temp sensor was an extra cost item.