simme avatar image
simme asked

Orion-Tr Smart 12v 18, overheating alternator?


A follow up to my previous question Continuously outputting 25A:

So I have an old Volkswagen T2 from 1971 that I have mounted this in. The alternator is, I think, 55A (there are 75A versions, but those seem rare and I can't easily check). From what I've been told by other enthusiasts there are often about 15A left over once the starter battery, lights and what not have had their needs satsified.

That's the information that I based by purchase of the Orion-Tr Smart 18 on (in tandem with recommendations from my Victron dealer). However, now that I know that the actual output may be greater than 18A and that I can see in the Bluetooth app for my batter that it is constantly receiving 25A when I'm running the engine I'm worried that this might overload the alternator.

I would appreciate any guidance I can get on this and if there's anything I can do to verify or check so that I'm not blowing up my alternator. My fear is based on this video by Victron.

Edit: The alternator is rated for 55A.


- Simon

Lithium Batteryorion-tr smartalternator
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1 Answer
jwfrary avatar image
jwfrary answered ·

Best way to know for sure if your alt is struggling is to monitor its temperature.

Would be benificial to work out exactly what you have as some alternators can regulate based on internal temperature. Others not. And a few other things.

If it’s not hot and your starter battery voltage is still good you likely ok!

Bear in mind if your say in a traffic jam and idling for a while you might want to disable the charger, as lower belt speed = less power and less cooling

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simme avatar image simme commented ·

Thing is, it is getting hot. Pretty darn hot. But it does that even without the charger there. So it's hard to tell, I'd have to get something to measure the temperature with then.

And I'd be very surprised if my 50 year old alternator could regulate itself. Hehe.

How do I measure the voltage of the battery? I have a multimeter. I assume I should measure with the car running and the charger active?

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simme avatar image simme commented ·

The alternator is 55A

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jwfrary avatar image jwfrary simme commented ·

All alternators have some kind of regulation/rectification as they have to in order to work! Some are more sophisticated than others

Multimeter on the battery, or rig up temporarily wiring so you can see it when your driving with longer wires.

You can get these little led lights which change colour depending on voltage, eBay might be a place to try. Ultimately you might be best to switch to a marine type alternator, a good alternator shop will be able to advise you.

Ps. If it’s 50 years old you have likely had the best years out of it and it might be time to switch to something from this century! ;-)

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