Balmar Alternator Temperate Protection Settings

[wingssail]

Originally Posted by tml

...I have been told and experienced that a single conventional belt will slip above 75 amps...

We have driven our 130 amp Balmar with a single 1/2" v drive belt, usually producing continuous 90 amps after a 130amp start up surge. For years we had excessive belt wear and carried several spares, usually whatever we could find at a local auto parts shop in wherever we happened to be. We never spent a lot of money on any special belts, they all worked about the same.

Finally, in 2009, after 16 years of wiping rubber dust off the front of our engine, we corrected the misalignment of the alternator mounting, and took out the slack in bolt and frame connection, thereby keeping the alternator in exact and firm alignment with the other pulleys. We also switched to a 2.5" pulley on the alternator, resulting in higher alternator RPM.

These two changes improved things: No longer do we experience belt wear. The normal automotive belts last for years now, and the smaller pully means we can get our 100+ amps out of the alternator at slower engine RPM.

[chowdan]

Originally Posted by philcun50

.
2. I installed an inline blower, no ducting, just points at the alternator to blow the hot air away from the alternator so it’s not sucked back in by the internal cooling fans.

I'd be curious if you reverse this and ducted the air away in a pull instead of push.

Obviously if you push external air onto the alt you'd be best

[GordMay]

Originally Posted by chowdan

I'd be curious if you reverse this and ducted the air away in a pull instead of push.
Obviously if you push external air onto the alt you'd be best

I recommend blowing on to a point source of heat (alternator), and exhausting out of an area (engine room), for best heat transfer.

Standing alone, the blow side of a fan produces a more concentrated, faster moving, and more turbulent "river" of air, compared to the intake side, where air is drawn almost equally from all directions. The turbulence greatly improves the efficiency of the heat transfer.
However, the heat not only has to be removed from your alternator, to air, but that hot air then needs to be removed from the vicinity. Failing do to so will just recirculate the hot air, and thermal failure can still occur on the alternator, you are trying to protect. As such your engine compartment needs to be vented, to draw in cool air from outside the enclosure.

[sailorboy1]

So no one has seen/read/can quote anythng from Balmar stating a different temp for their alternators. I dud find a Balmar spec saying basicall all their alternators the spec max temp was 100C. But the default on my ARS5 regulator is 108C. So i find it strange that Balmar would ship a regultor with an 8% higher setting than their on alternator spec.

My initial original question remains: is the default 108c alternator temp set point of my ARS5 regulator acceptable to protect my alternator? If not can you provide a source for the info?

[tml]

Originally Posted by sailorboy1

So no one has seen/read/can quote anythng from Balmar stating a different temp for their alternators. I dud find a Balmar spec saying basicall all their alternators the spec max temp was 100C. But the default on my ARS5 regulator is 108C. So i find it strange that Balmar would ship a regultor with an 8% higher setting than their on alternator spec.

My initial original question remains: is the default 108c alternator temp set point of my ARS5 regulator acceptable to protect my alternator? If not can you provide a source for the info?

Sailorboy
Why not call Balmar and ask? They are pleasant to talk to but good luck getting a straight answer. Interesting to hear their answer.
As previously stated my source is my own experience. Until I reset to 100C the alternator failed 3 times; the worst a flaming fire in the engine compartment.
Tom

[a64pilot]

I don’t think there is a straight answer, I believe that within limits the hotter your run one the shorter it’s life, Yes there is an approximate temp that will cause immediate failure, but who knows what that is, and why would it matter?
I have my Mark Grasser 165 alt set to belt manager 4 based off of Maine Sails recommendation and I set my temp limit at 90C, based off of my own opinion.
Even with a belt manager setting of 4, my alt still temp limits at about 90 amps at 90C, I believe that if temp protected belt manager settings are sort of irrelevant, but higher settings will limit the alt and it’s heat build up will be slower due to its lower output, but that eventually it’s temp that limits them.
it should be noted that there is a hot side to an alternator and of course the hot side is the side the diodes are on, which is the starboard side of a small frame alternator, so mount your temp sensor on that side.

My belief is that pretty much all small frame alternators above 100 or so amps will put out about the same continuous power as they are limited by cooling, and this cooling is the same with all of them etc.
Now some big alts may be slightly more efficient and greater efficiency will mean more power with less heat, but I bet it’s not much.

108C is likely a number that gives what Balmar accepts as an acceptable life, question is, what is that?
But I bet that lower temps will greatly extend the life, that’s why I picked 90C, but then as I wake up with a bank at about 75% SOC, 90 amps is plenty for me as the bank will only accept that for a short time, only time I really need high output is if I run my Watermaker off of the inverter, but I almost never do that.

[sailorboy1]

Because tech opinions are tech opinions and to me just an individual opinion even if based on whatever. Meanwhile a written spec is official numbers from a company.

[wingssail]

Originally Posted by sailorboy1

So no one has seen/read/can quote anythng from Balmar stating a different temp for their alternators. I dud find a Balmar spec saying basicall all their alternators the spec max temp was 100C. But the default on my ARS5 regulator is 108C. So i find it strange that Balmar would ship a regultor with an 8% higher setting than their on alternator spec.

My initial original question remains: is the default 108c alternator temp set point of my ARS5 regulator acceptable to protect my alternator? If not can you provide a source for the info?

As I mentioned up thread Balmar advised me to reset the temperature limit on my 79-110 to 112C to prevent output reduction.

But your question "is the default 108c alternator temp set point of my ARS5 regulator acceptable to protect my alternator" misses the main point: All alternators will eventually fail. Heat is one of the biggest causes of failure. Hotter temperatures, such as 108C, may not cause it to fail right away, but it is likely to shorten the life of the alternator.

It seems to me that 108C will protect your alternator from instant melt down, but it will not protect your alternator from ultimate failure or possibly shortened life. Balmar apparently considers 100C to be the best setting for long life. They do not publish a graph comparing life to temperature

[sailorboy1]

Originally Posted by wingssail

It seems to me that 108C will protect your alternator from instant melt down, but it will not protect your alternator from ultimate failure or possibly shortened life. Balmar apparently considers 100C to be the best setting for long life. They do not publish a graph comparing life to temperature

Which again brings the question full circle. If Balmar feels 100c is the best for the alternators, why does Balmar put a default of 108C in the regulator?

[wingssail]

Originally Posted by sailorboy1

Which again brings the question full circle. If Balmar feels 100c is the best for the alternators, why does Balmar put a default of 108C in the regulator?

Well sailorboy1, this is interesting. I never looked at their documentation, only the LED read out on the units (I've had a few). They consistently start backing off on the field when the AL1 goes over 100C.

But today, because of your questioning, I looked at the Balmar document I got with my ARS5 this summer. It says the default for AL1 is 108C!!!

So I guess this is question for Balmar.

You can call them.
Technical Service: 1.360.435.6100 x314 Dale English S.C
x320 Carl, Arlington, WA.

Good luck.

[sailorboy1]

I lost track of this topic, but send in the question to Balamar. Below is response:

"The previous limit was set for 108C but we found that some alternator continued to climb in temperature so we dropped the limit to 100C to give us a little more "head room". The alternator is a changeable value in Advanced Programming. You can set it down to 100C if you feel your alternator is getting too hot.

Best Regards,
Thomas Pusateri"

[philcun50]

Exceptional thread Sailorboy1.
When I installed my Balmar regulator I did heaps of research and the common temp pointed to 225°F (107°C).
Now as pointed out in my earlier reply, my alternator due to improvements I have made to cooling of the alternator runs at about 87°C producing 114amps (about 80amps charge).
The point I make is if you can get it to function like mine try setting the temp limit to something lower e.g. 90°C if your worried that 100°C is too high. If your happy with the amount of charge at that point Bob’s your uncle.
I don’t believe the temp sensor really gets the right temp due to poor contact with the alternator and thus the internal temp is a lot higher.
When motoring ceases before the tail current kicks in (100% charge) the alternator stops with high internal temp saturation which I believe causes a lot of deterioration. My intention is to fit a switch to turn off the field to allow the alternator to cool while still rotating.
I reiterate, just set it lower and see if your happy with the charge current.

[bgallinger]

I have a 100 A Balmar alternator and MC-614 regulator. I would like to add a cooling fan, but mounting space is limited. Is there a fan on the market that I could attach directly on to the alternator?
Is this necessary? A good idea or not?

[philcun50]

I have made 2 posts to this thread. My first talks about the success I had just cable trying to an engine mount, an inline Rule blower just pointing at the alternator with no ducting. It blows the hot air coming out of the alternator away so it's not sucked back into the alternator. Of course the engine bay temperature will climb if you don't have it ventilated usually with an exhaust fan.
By doing this I picked up an extra 22amps out of the alternator which gave me 7 amps for the fan and 15 amps extra charge. The alternator"s external temperature is about 87°C.
I have read of people installing ducting and going to all sorts of extremes to mould a cowl round the alternator but being lazy my fan sat on the boat for at least a year until I thought of just doing what I did. Much more effective that sitting on a shelf, LOL
My answer is yes it is a good idea to have a fan and to make sure your engine bay fan is working. If you need to replace the engine bay fan remember that most of the cheap fans on the market are only intermittently rated. They are for getting fumes out before starting petrol engines. You need a continuously rated fan which are more expense. If the fan's rating isn't stated then it will be intermittent. My original blower failed I bought a second it failed even quicker then I cottoned onto why.

[sailorboy1]

I read a magazine article from Nigel Calder years ago about the high amp alternators and adding a cooling fan. Probably worth a search for those having issues.