DC to DC charger - not needed for boats with proper alternators.

[noelex 77]

The fact that it has been running well is promising, but I am still puzzled why you have unplugged the alternator temperature sensing wire. This is a safety mechanism to prevent the alternator overheating. Like any safety mechanism it may only be triggered rarely, but it is still nice to have.

[Fuss]

Originally Posted by noelex 77

The fact that it has been running well is promising, but I am still puzzled why you have unplugged the alternator temperature sensing wire. This is a safety mechanism to prevent the alternator overheating. Like any safety mechanism it may only be triggered rarely, but it is still nice to have.

I plugged it back in now, but it doesn’t do anything as the temp parameter is set high. I only bought the temp cable as I was worried about the Lifepo4.

[newhaul]

Originally Posted by Fuss

I plugged it back in now, but it doesn’t do anything as the temp parameter is set high. I only bought the temp cable as I was worried about the Lifepo4.

I'm sure you said before but what brand of batteries did you install?

[noelex 77]

Originally Posted by Fuss

I plugged it back in now, but it doesn’t do anything as the temp parameter is set high. I only bought the temp cable as I was worried about the Lifepo4.

Plugging it back in is a good move. It will presumably kick in and reduce, or eventually kill the output if the alternator runs hotter than normal. This is important, especially when you are pushing the envelope.

If you think the temperature is set too high and this protective function may not work, the temperature limit for the regulator can usually be easily adjusted.

[Simi 60]

Originally Posted by Fuss

That’s true, the reason I don’t want to change anything is that it has been working this way for a long time and has not burnt out the alternator and so I’m leaving it as it is. Partly as a test.
There is one difference however, and that is that the old batteries were lead acid and the new are Lifepo4.
However the alternator put out full power for more than an hour with this setup and it does the same with the Lifepo4.
I believe that if an alternator puts out full output with lead acid for an extended period, then with Lifepo4, then it will not be more stressed…however many forum members have a different opinion so this might have to be a separate thread to shoot down this myth.

Since when has a bit over an hour been an extended period?

Our 840ah @ 24v battery bank takes how long to fill at 50 to 70amps in?

[sailingharry]

I think that the distinction is not the difference between 1 hour and the 10 hours it would take to fill your bank. Rather, it is a response to those that say that LFP will kill an alternator because with lead, the alternator does not run at full output before the battery hits acceptance (hogwash). If an alternator is at max output (appropriately dialed down by regulator to control temp) for an hour, it has reached steady state. All internal parts are at peak operating temp, and further run time is more of the same.

[s/v Jedi]

Simply lower the temperature setting in the regulator to see if it works.

[newhaul]

Iirc fuss is running Battleborn batteries. Their bms is specificly only allowing for 100amps charging . So a 150 amp alternator is only running at 60% approx of its potential output.
This would easily explain his numbers .
Unlike tho see of us running banks we built ourselves. My little 250ah would likelybcook his alternator as it will accept up to 300 amps charging. ( bms controlled) .

[noelex 77]

Originally Posted by newhaul

Iirc fuss is running Battleborn batteries. Their bms is specificly only allowing for 100amps charging . So a 150 amp alternator is only running at 60% approx of its potential output.
This would easily explain his numbers .

The charge limit of 50A or 100A (for emergency situations) applies to each Battleborn 100Ahr battery.

If the battery bank has more than one battery in parallel, the total charge current will be additive (or close to additive). So, for example, a 400Ahr bank would accept 200A (or 400A in an emergency) of charge current (or close to this).

[newhaul]

Originally Posted by noelex 77

The charge limit of 50A or 100A (for emergency situations) applies to each Battleborn 100Ahr battery.

If the battery bank has more than one battery in parallel, the total charge current will be additive (or close to additive). So, for example, a 400Ahr bank would accept 200A (or 400A in an emergency) of charge current (or close to this).

That would make sense however according to their literature it isn't cumulative.

[SaylorMade]

Originally Posted by newhaul

That would make sense however according to their literature it isn't cumulative.

From their manual:

"Multiple BB10012|BB10012H batteries may be connected in parallel to increase the capacity and current of the
system. When batteries are connected in parallel, the voltage of the system does not change, but the capacity and
current limits are additive. "

[newhaul]

Originally Posted by SaylorMade

From their manual:

"Multiple BB10012|BB10012H batteries may be connected in parallel to increase the capacity and current of the
system. When batteries are connected in parallel, the voltage of the system does not change, but the capacity and
current limits are additive. "

Confusion wrt the numbers and specific language so sent email to them for clarification.

[Fuss]

Originally Posted by newhaul

Iirc fuss is running Battleborn batteries. Their bms is specificly only allowing for 100amps charging . So a 150 amp alternator is only running at 60% approx of its potential output.
This would easily explain his numbers .
Unlike tho see of us running banks we built ourselves. My little 250ah would likelybcook his alternator as it will accept up to 300 amps charging. ( bms controlled) .

I’m running Eve LF280K, 560ah 24v, I wouldn’t run battleborn as I have restricted space and Eve lf280k fits to within the mm.
The BMV712 says 150ah…often for an extended period, like 5 hours on occasion but generally over an hour.
150ah is 150ah unless the 712 lies…130-140 degrees is the temp that the alternator runs at after it stabilises …but measured from one of the bolts on the outside then probably 110 degrees C.

[Stu Jackson]

Originally Posted by Fuss

I’m running Eve LF280K, 560ah 24v, I wouldn’t run battleborn as I have restricted space and Eve lf280k fits to within the mm.
The BMV712 says 150ah…often for an extended period, like 5 hours on occasion but generally over an hour.
150ah is 150ah unless the 712 lies…130-140 degrees is the temp that the alternator runs at after it stabilises …but measured from one of the bolts on the outside then probably 110 degrees C.

Might you still be confusing amps and amp hours?

[Fuss]

Originally Posted by Stu Jackson

Might you still be confusing amps and amp hours?

Yes, probably, what does the BMV 712 measure STU when it says AH?