Balmar Max Charge MC-612 Question

[dksail]

We have an MC-612 that regulates the alternator. The alternator charges the lithium house bank and the house bank charges the other batteries (start/bow thruster) via Duo Chargers.

Our alternator is not putting out hardly any amps as it is seems to be reading the battery voltage incorrectly. After running the batteries down by 25% while at anchorage, we started the boat and motored away. While watching the data, mode 7 on the MC-612, which is the battery voltage goes quickly from 13.2+- to 14.4+-(within a few minutes). Mode 9 which is the bulk, or target voltage is 14.4.

Therefore, as far as I can tell, the regulator thinks the batteries are about full and reduces the charge to about 15 amps (80 amp alternator) or absorption mode. I checked the voltage at the alternator while running and it matched the 13.2, all other voltage checks on the battery system were at 13.2 as well.

I have run the suggested tests and checks on the regulator and Balmar support has yet to give me any advice, only to say the tests check out, which was true.

Anyone have any ideas?

[smac999]

The absorbstion mode should be the same voltage as bulk.

Are you sure it’s not going to float? Or is your absorbstion voltage set to low?

On the mc 14 the absorb timer is only 15 mins. So I have to raise all of them so it does not float early. I’m not firmilur with the mc12.

[CharlieJ]

MC-612 has the same features as the MC-614 but controls two alternators on the same engine. OP: what is your setup...do you have two alternators on one engine?

[dksail]

There should be no reason for it to go to float until it reaches the 14.4 target, which according to all of my other voltage reading devices, it doesn’t.

The boat originally came with a Balmar dual output alternator,. Maybe there is something going on with that?

[dksail]

SMAC999. I will double check the absorption setting to make sure it is set at the same 14.4.

[smac999]

The other thing to look at is where the voltage sense is taken from and the cable loses.

Ie an alternator at 80a. Might be 14.4v at alt post and 13.8v at battery due to cable lose. If the voltage sense is taken at alt post. The batteries will Never get over 13.8v in bulk in that example. Ideall voltage sense is taken from battery. And alt cables are big.

[CharlieJ]

I have a fair bit of Balmar alternator experience but I can't recall a "dual output" model. I also do not understand your description of "mode 7" and "mode 9". These are unfamiliar terms with Balmar regulators.

By your description, I think you are referencing bv = battery voltage and cv = calculated bulk/absorption knee voltage. What is the belt manager set at? What does the "state of charge" (Balmar-speak for what stage the multi-stage regulator is in) show while getting underway from the anchorage?

Can you supply a listing of the settings for the Balmar? That would be helpful in trying to help you troubleshoot.

[dksail]

Thanks SMAC999. The voltage sense is at the batteries, and the alt cable is 2/0 with only a 8 foot run. Should be okay there.

[dksail]

Thanks Charlie. I took a video video of the regulator soon after we left anchorage... Here are the results:

Bv = 14.3
Cv = 14.4
P03 = gel
S03 = Bulk

[CharlieJ]

There are some warning signs that whoever progammed this may not have fully trained.

For example; the "gel" setting has a high voltage limit of 15.1VDC which would be injurious of your LFP bank if the BMS didn't protect it; there should be no temperature compensation; belt manager has to match the alternators heat rejecting capacity to the electrical load; etc., etc.

Tough to troubleshoot long distance. I recommend that you find somebody with Balmar experience and have them reprogram this for your application.

[dksail]

Thanks Charlie: we set the bulk settings to. 14.4 as indicated, so I don’t know why the unit still references the Gel battery. The settings all seem good, it just seems to be the voltage reading that the unit is incorrectly seeing. It still might have something to do with the dual charge alternator. I will be checking on that. Your input is greatly appreciated.

[smac999]

on the 614. you can adjust the settings for each battery type. so if you choose gel, and then adjust the voltages of gel. those get saved as gel. if you then change to flooded, new flooded voltages will be used. and you could then ajust those.

when it says bv is 14.3 and cv 14.4. what is the actual measured battery voltage? is it 14.3?

so what happens shortly after? it drops to bv 13.x and cv 13.x? and is in absorb mode? my guess is the absorb voltage is too low. on the 614 the bulk, absorb, and float are 3 different settings to change. it looks like the default gel absorb voltage is 13.9 you should make it 14.4 if that is what you want.

also disconnect any battery temp sensors if charging Li

if you choose the li mode for battery type it will disable the temp comp for you instead of disconnecting batteries. then check all 3 voltage settings for Li

[Maine Sail]

The voltage sense circuit needs to be wired correctly, most are not.

https://marinehowto.com/alternators-voltage-sensing/

[Nicholson58]

Originally Posted by CharlieJ

There are some warning signs that whoever progammed this may not have fully trained.

For example; the "gel" setting has a high voltage limit of 15.1VDC which would be injurious of your LFP bank if the BMS didn't protect it; there should be no temperature compensation; belt manager has to match the alternators heat rejecting capacity to the electrical load; etc., etc.

Tough to troubleshoot long distance. I recommend that you find somebody with Balmar experience and have them reprogram this for your application.

When we considered LFE I found that Balmar had a software update you could load for Lithium so the Balmar would operate with the correct profile for Lithium. Float should be eliminated and the rest of the profile is simplified.

If your alternator is not rated for continuous full load output it may be damaged (overheating) with big LFE or AGM batteries. I smoked my alternator charging a big Firefly bank while motor-sailing for many hours. After that, it has been unreliable but occasionally working.

[dksail]

The actual voltage was 13.2 and was verified manually with a Fluke at the alternator. The bulk and absorption modes were programmed at 14.4.

I checked the voltage sensor wiring and the manual gives you the option to connect it to the alternator positive lead which it is. That is where I measured the 13.2 but regulator was reading 14.3.