I recently installed a Balmar 6-series (100A) alternator on my sailboat to replace the stock 60A alt that came from Yanmar. So far, it has been great. This is the first alternator I've owned that has an alternator temperature sensor on it, and while I know that when/if it gets TOO hot, my sensor/regulator will work to protect it, I'm wondering what a "normal" temperature would be. Obviously everyone is going to have different setups, different ventilation, etc. etc... so I know I'm not going to get back an EXACT number, but just curious at what range I should be comfortable. I think I saw 230F listed somewhere as the maximum operating temp before the sensor starts limiting things to protect it, but certainly there must be some "normal" I should be shooting for that's better than just being below the max. I've been keeping an eye on it, and the hottest I've seen it get up to was around 190F... but most of the time when it's not being pushed it's MUCH lower than that... more like 150F. I initially set the belt load manager setting on my ARS-5 regulator to "4" which means my 100A alt is more or less now an 80A alt... but admittedly that number was somewhat arbitrary when I did the initial setup, and I'd like to adjust it further now that I've seen the alternator working in action, and temperature seems like an important part of that equation. Anyone have advice on what temp range (other than the obvious "the cooler the better" I should be shooting for)? Thanks.
Alternator Temperature
- Thread starter ToddS
- Start date
I have a CMI-105-ER alternator. Rated for 105A. I have a Xantrex XAR external regulator that I think is equivalent to a Balmar ARS-4. I have the Amp Manager set to 70% so the output will be about 65-75A. My house bank is 460AH (4- 6V GC batteries).
IIRC, at bulk output I have measured the alternator case about 170 degrees and at a 30A output in absorption mode the temp is more like 140 degrees.
I also have a dedicated blower to exhaust hot air from around the alternator to an outside vent. I think that helps a lot.
IIRC, at bulk output I have measured the alternator case about 170 degrees and at a 30A output in absorption mode the temp is more like 140 degrees.
I also have a dedicated blower to exhaust hot air from around the alternator to an outside vent. I think that helps a lot.
Thanks Rich, that's a little cooler than mine, but not drastically so. I also have a blower in the engine compartment, but could work some work and lengthening of hoses get it closer to the alternator...
The alternator diodes are likely rated for a junction temperature of 150C (300 F) the wire in the alternator is likely insulated with 155C (310F) insulation. So those components can be quite hot indeed. Wherever you measure temperature will be somewhat distant from those critical components and at a lower temperature.
Very true. The diodes are probably the hottest part and they are heat-sinked to the case. I measured the case temperature at the location of the attached regulator temperature sensor.
I'd like to know this too. I just replaced my Ample Power regulator with a Balmar 614. I wired up a temp sensor to the Venus GX and saw steady 50-60°C (120-140°F) while motoring for a couple of hours with a moderately discharged bank. The alternator (a 100 A Ample Power) was putting out around 50 amps at the time. If I had a better sense of the operating range I could change the belt manager setting and turn up the amps a bit.
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jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,378
Mermike, We benefit from sailing in a location that stays relatively cool. This is an aide to our boats and systems.
You can up the "juice" on the 614, but with caution. The belt manager is more about the engine belt and eliminating dust/belt wear than temp management. The issue of temp just comes as a bonus and a preventer of machines running amok.
No time like the present to do a little experimentation - tweaking... Just a little bit....
You can up the "juice" on the 614, but with caution. The belt manager is more about the engine belt and eliminating dust/belt wear than temp management. The issue of temp just comes as a bonus and a preventer of machines running amok.
No time like the present to do a little experimentation - tweaking... Just a little bit....
Yes, the tweaking is about to commence. Within limits of course. Whatever they may be. I need 90 amps to hit .4C. Probably not going to safely get there, but I'd like to get closer.
