I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

Craig,

I recently asked a similar question elsewhere about this, from a marine
electronics expert, and received this reply (I hope he won't mind me quoting
him):

====

Will hours and hours of full-alternator charging output damage the
alternator? I know an alternator rebuilder around here who says yes, but I
have heard "experts" up and down the dock with every opinion from here to
Sunday.

REPLY
The short answer is YES!
If the litle alternator gets over heated then the wires will scorch and once
you loose the insulation, they short out.

The rectifier diodes will also suffer damage if subjected to too much heat.
How much is too much? Maximum case temp should not exceed 180F

Beyond that and you can expect permanent damage to something inside the
alternator.

====
--

====

Charles T. Low
www.boatdocking.com

====


"Craig Stuart" wrote in message
nk.net...
I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

On Sun, 05 Sep 2004 22:19:44 GMT, "Craig Stuart"
wrote:

I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

No. In fact as a rule of thumb: if you'd like electrical equipment to
last for ever, ensure that you can (just about) rest your hand on it
for at least a few seconds.

Brian W

Craig and Marcia:

230 degrees is too hot. BTW, how are you measuring this temp?

There are two solutions:

Some regulators, Balmar's MaxCharge in particular, have a temperature probe
option. With this, at least on the Balmar, it will reduce charging current
to about one half when it senses temperatures that are too high. The lower
charging current will reduce the case temperature rather quickly- in a few
minutes, then it will return the alternator to its original charging rate.
This will cycle on and off to keep the alternator temperature within bounds.
I recall talking to the Balmar tech, who told me that it reduces charging
current when the case temperature reaches 180 deg F.

But this is only a stop gap fix. The real fix is to increase the cooling
airflow to the alternator. The standard air flow is from the back of the
alternator to the front. On my sailboat with a very tight engine enclosure,
I added a small 12 volt muffin fan which ducts cool bilge air up to the back
of the alternator. With the fan running, the temperature control circuit in
the Balmar alternator never cuts back the current. Without it, the current
is reduced at least half the time, thereby cutting your charging rate
significantly.

David

"Craig Stuart" wrote in message
nk.net...
I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

I have been struggling with alternator overheating for 3 months now. I
installed a Balmar 612-110 (new model) on my system (420Ah battery bank) and
am experiencing overheating. Within minutes, I reach 230F, which is the
point at which my regulator reduces output by half (I have a temperature
controller installed on the alternator). Balmar is trying to help and has
sent me 2 other alternators (another 612 and one 700 series), but they all
overheat. Neiter I nor Balmar understands what is going on (they claim they
tested the alternators before they shipped and they ran at full output at
around 180F). My engine compartment is pretty tight, especially in front of
the alternator there is the engine hatch. May be there is not enough air
flow. I checked everything else and it all looks correct.

I finally mounted a blower with tubing bringing cool air from the outside
right to the back of the alternator. With that the alternator does not go
into small engine mode (as I am blowing air on the temperature sensor...)
but the face (front side) of the alternator reaches a temperature of 244F. I
wonder how long the alternator will last this way.

Temperature was measured using a thermocouple attached to the alternator
using thermal grease.

Any experiences? Any suggestions welcome.

Sam

"Craig Stuart" wrote in message
nk.net...
I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

Are the cooling fins on the pully turning in the correct direction to
cool the alternator?
krj

Sam wrote:
I have been struggling with alternator overheating for 3 months now. I
installed a Balmar 612-110 (new model) on my system (420Ah battery bank) and
am experiencing overheating. Within minutes, I reach 230F, which is the
point at which my regulator reduces output by half (I have a temperature
controller installed on the alternator). Balmar is trying to help and has
sent me 2 other alternators (another 612 and one 700 series), but they all
overheat. Neiter I nor Balmar understands what is going on (they claim they
tested the alternators before they shipped and they ran at full output at
around 180F). My engine compartment is pretty tight, especially in front of
the alternator there is the engine hatch. May be there is not enough air
flow. I checked everything else and it all looks correct.

I finally mounted a blower with tubing bringing cool air from the outside
right to the back of the alternator. With that the alternator does not go
into small engine mode (as I am blowing air on the temperature sensor...)
but the face (front side) of the alternator reaches a temperature of 244F. I
wonder how long the alternator will last this way.

Temperature was measured using a thermocouple attached to the alternator
using thermal grease.

Any experiences? Any suggestions welcome.

Sam

"Craig Stuart" wrote in message
nk.net...

I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

Sam:

There seems to be a lot of alternator overheating going around. See my reply
to Craig and Marcia below. But you seem to already have done all of what I
suggest below. But if your temperature probe is mounted to the case screws
and the regulator is not cutting back on current, then you probably are
operating within an acceptable temperature. FWIW however when I installed my
muffin fan and duct, I sensed a noticable drop in case temperature with my
highly calbrated index finger. And I don't think that the increased airflow
was only cooling the temperature probe. I think it was cooling the whole
alternator.

David

Craig and Marcia:

230 degrees is too hot. BTW, how are you measuring this temp?

There are two solutions:

Some regulators, Balmar's MaxCharge in particular, have a temperature probe
option. With this, at least on the Balmar, it will reduce charging current
to about one half when it senses temperatures that are too high. The lower
charging current will reduce the case temperature rather quickly- in a few
minutes, then it will return the alternator to its original charging rate.
This will cycle on and off to keep the alternator temperature within bounds.
I recall talking to the Balmar tech, who told me that it reduces charging
current when the case temperature reaches 180 deg F.

But this is only a stop gap fix. The real fix is to increase the cooling
airflow to the alternator. The standard air flow is from the back of the
alternator to the front. On my sailboat with a very tight engine enclosure,
I added a small 12 volt muffin fan which ducts cool bilge air up to the back
of the alternator. With the fan running, the temperature control circuit in
the Balmar alternator never cuts back the current. Without it, the current
is reduced at least half the time, thereby cutting your charging rate
significantly.

David

"Craig Stuart" wrote in message
nk.net...
I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

Yes they are! The pulley is turning clockwise.

Sam

"Kelton Joyner" wrote in message
news
Are the cooling fins on the pully turning in the correct direction to
cool the alternator?
krj

Sam wrote:
I have been struggling with alternator overheating for 3 months now. I
installed a Balmar 612-110 (new model) on my system (420Ah battery bank)
and
am experiencing overheating. Within minutes, I reach 230F, which is the
point at which my regulator reduces output by half (I have a temperature
controller installed on the alternator). Balmar is trying to help and
has
sent me 2 other alternators (another 612 and one 700 series), but they
all
overheat. Neiter I nor Balmar understands what is going on (they claim
they
tested the alternators before they shipped and they ran at full output
at
around 180F). My engine compartment is pretty tight, especially in front
of
the alternator there is the engine hatch. May be there is not enough air
flow. I checked everything else and it all looks correct.

I finally mounted a blower with tubing bringing cool air from the
outside
right to the back of the alternator. With that the alternator does not
go
into small engine mode (as I am blowing air on the temperature
sensor...)
but the face (front side) of the alternator reaches a temperature of
244F. I
wonder how long the alternator will last this way.

Temperature was measured using a thermocouple attached to the alternator
using thermal grease.

Any experiences? Any suggestions welcome.

Sam

"Craig Stuart" wrote in message
nk.net...

I have a Balmar alternator and when it is charging the temp of the
alternator is around 230 degrees. Is this normal ?

--
Craig & Marcia Stuart

I've been following this thread a bit.

Good Lord!

What all are you pulling that would make the alt. run wide open? the
Alternator shouldn't be forced to pull any harder than ia max. of 75%
of it's capacity.

and by hooking a blower up to run cooler air to the alt. will only make
the alt. pull that much harder .

And what tickles me is that some of these companies will take an alt.
that was designed for say, 60 amps, then they will hot-rod it up to
about 175 or 220. by stuffing it full of wires and saying "this is
what you need" (gulp!) and charging you extra big bucks for something
that would requier special servicing.

I would advise checking and seeing how much your actual amperage pull
is (if you have a 100 amp draw, you need at least a135 a.rated "stock"
unit) , THEN go get a stock OEM unit (prestolite/leece-neville, large
frame Delco, Bosch etc.) and work with that. i think you'll get more
satisfactory results, and less cost involved as well.

Tim

You need to learn more about the requirements of a marine
charging system. Alternator requirements have only little to do with
loads directly supported by the alternator. High charge rates are used to
recharge a large battery bank in a short period of time.

Doug
s/v Callista

"Tim" wrote in message
ups.com...
I've been following this thread a bit.

Good Lord!

What all are you pulling that would make the alt. run wide open? the
Alternator shouldn't be forced to pull any harder than ia max. of 75%
of it's capacity.

and by hooking a blower up to run cooler air to the alt. will only make
the alt. pull that much harder .

And what tickles me is that some of these companies will take an alt.
that was designed for say, 60 amps, then they will hot-rod it up to
about 175 or 220. by stuffing it full of wires and saying "this is
what you need" (gulp!) and charging you extra big bucks for something
that would requier special servicing.

I would advise checking and seeing how much your actual amperage pull
is (if you have a 100 amp draw, you need at least a135 a.rated "stock"
unit) , THEN go get a stock OEM unit (prestolite/leece-neville, large
frame Delco, Bosch etc.) and work with that. i think you'll get more
satisfactory results, and less cost involved as well.

Tim