Underperforming Balmar alternators

[Dedzaboy]

I have a catamaran with two engines to which I have just fitted two Balmar 100A alternators with Balmar ARS-5 regulators. My battery monitor tells me that the battery bank (520ah AGM) is only 60% charged yet when I start one engine (either one) the alternator / regulator only delivers 50A or so, for a short while, before tailing off over a period of an hour or so to "float" mode and 10 amps or less. This is less effective charging than the original Hitachi 60A alternators without smart regulation, so something's wrong somewhere! Balmar haven't yet responded to my email queries but then it is Christmas...does anyone have any ideas?

[btrayfors]

Would have to know more to be sure. But, I'd suspect that the battery monitor isn't reading correctly, because you get the same performance from two separate 100A alternators and smart regulators. It's possible that the battery monitor isn't set up for AGM's. AGMs and gelled batteries exhibit higher voltages at comparable states of charge vs. flooded batteries at the same charge state.

Another possibility is that neither ARS-5 regulator is set up correctly for AGM batteries.

Suggest you read the manual for this regulator carefully, check all connections, and be sure the ARS-5's are set up for AGM batteries.



Bill

[Dedzaboy]

Bill,
The battery monitor is by Mastervolt and as far as I know works out the depth of discharge by keeping count of the amp drain and amps put back in, and therefore amp-hours, from the time when I told it that the bank was charged and was 520ah.
Right now it's showing 12.7V but "capacity consumed" is 199ah, "battery status" 63% (voltage may be higher than expected since solar panels are charging at the moment).
I've double checked all settings and the regulator is set up for AGM batts.

Neil.

[Badsanta]

I would recheck the mastervolt. When Installed mine (not mastervolt) it was very clear that the battery had to be fully charged and then set to the battery size and would have to reset at times, because it really does not know what is in the battery, it just measures electric flow back and forth and needs a starting point. with your rewiring, it may have forgot where it is and may need reseting.

[btrayfors]

Yes, Badsanta is right. Also, the solar panels output could be confusing to the regulator.

Battery voltage is virtually meaningless unless you know your system well or unless the batteries have been "resting" with no charge and no discharge for several hours (a full day is better).

Some devices onboard may be wired directly to the battery, so the Mastervolt may not keep track of them. Typically, SSB radios, bilge pumps are in this category.

Here are some reference voltages: Gallery :: Miscellaneous 2007 :: SOC

But these only apply after the batteries have been resting, as noted above.

Bill

[Viking Sailor]

If possible, I suggest that you disconnect all charging sources, load the battery bank to discharge about 20 to 50 Ah, disconnect all loads from the battery bank and let it rest for about one hour. Then recharge using the alternator with no other charging sources connected and no loads connected.

I believe that your problem is that the alternator regulator is confused by the solar panel charging and possibly loading of the battery during charging. The above puts you back to a know state. If the above doesn't work then there is a real possibility that one or more of your batteries are failing.

[hellosailor]

I'd also vote for the solar panels confusing the regulators. It should be simple enough to disconnect them and see what happens, but if the solar panels are feeding up to 17 volts into the batteries, and the regulator sense wire "sees" that extra voltage, it will promptly cut back the alternator.

You might want to add in either a manual switch, or a charging relay, to cut the solar panels off from the batteries while the engine is running. I don't think anyone is marketing a fully integrated charge controller that magically allows alternators and solar panels to both charge the same battery at the same time, I suspect there's no simple [costwise] way to tell a conventional regulator "ignore the output from the solar panels".

[Therapy]

Please post your solution.
I would very much like to know the outcome.

Thank you.

[Therapy]

This problem of charging from multiple sources has always interested me because I plan to have multiple charging sources and want it to work. So far it seems to me it can work but is not automatic.

From another board:

I have solar panels and noticed that my alternator would ramp down too soon during the acceptance phase. My conclusion agrees with the above that my Ample Power regulator senses the higher voltage from the solar panels and ramps down even though the amperage output from them is much smaller. BTW when on shore power my inverter/charger does the same thing. My solution is simple and low tech. I have a togle switch at the engine panel that I use to turn off the solar panels when I'm trying to charge from the alternator. It's not automatic but it works.

[rdempsey]

Originally Posted by Therapy

I have a togle switch at the engine panel that I use to turn off the solar panels when I'm trying to charge from the alternator. It's not automatic but it works.

How about a relay energized when the engine is on, which disconnects the solar? That would automate it.

[Therapy]

Originally Posted by rdempsey

How about a relay energized when the engine is on, which disconnects the solar? That would automate it.

Somewhere I think someone said they would try it or they have tried it, can't remember.
Certainly seems simple enough.

[Dedzaboy]

Yep, I'd already considered that the solar panels may be confusing the Balmar regulators so had disconnected them but this made no difference. Actually, the "Blue Sky" regulator that I have seems to disconnect the solar charge pretty much as soon as I start the engine anyway, presumably because the voltage rises so the solar regulator cuts in. I'll keep plugging away at the problem and will let you all know the outcome - thanks for your help.

[donradcliffe]

Its time to get out the old digital voltmeter and make a few measurements. First, when the batteries are down and the engine is first started, measure the battery voltage across its terminals. If the battery voltage is below the specified acceptance voltage (say 14.2 for AGM's), then the Balmar regulator should be telling the alternator to go flat out, and the field voltage should be at nearly (within 0.5 volts of) the battery voltage. The Balmar regulator's sensing voltage should be the same as the battery voltage. The Balmar alternator output voltage (across its terminals)should be less than 0.5 volts above the battery voltage, unless you have a diode-type battery isolator, in which case the alternator voltage should be less than 1.0 volts higher. If all this is the case and your 100A alternator is still only putting out 50 amps (remember that if you are reading amps going into the battery, you need to add all the boat panel loads plus about 5 amps for the field to get alternator output), them maybe your alternator is sick, and you need to have someone check its diodes.

If all is working well, with time the battery voltage will rise to the acceptance level and stay there while the charging current (and the field voltage) will start tapering off. As the current drops to 25 amps, the field voltage should be down to perhaps 8-9 volts.

Unless you have a massive array, the solar panels shouldn't affect the alternator and regulator much--15 amps of solar is only 15% of the alternator output. If you're worried about it, try the alternator test at night.

If the voltage drop between the alternator output and the batteries is high, test across each connection, both positive and ground, till you find the culprit. If you don't have a separate heavy ground wire to the alternator case, its a likely candidate for problems.

You can also shortcut the regulator circuit by taking a wire straight from the positive battery terminal to the field terminal of the alternator for minute or two--if the alternator output jumps up to new highs, you have a regulator issue. Although at least the old Balmars were pretty good at putting out rated power, a lot of alternators are rated at unrealistically cool temperatures, and under normal operating conditions they may only put out 80% of rated amps as they heat up.

Finally, don't try too hard to get the full rated output--I ran into a guy in the Solomons who had burned out all 3 of his alternators, because they really couldn't handle continous operation at rated output--80% of rated is better than zero.

[rleslie]

It could also be something as simple as a loose sensor wire from your ARS-5 to the bank. You may want to disconnect/clean all of the wires involved.

I'm certain that you have already done this..... verify that your belts are of proper tension.

[hellosailor]

"Actually, the "Blue Sky" regulator "
Regulator? Or an MPPT charge controller? There's a big difference, the MPPT controllers that BS make put out pulsed DC, and that kind of signal is going to confuse the hell out of a conventional regulator.
I'd suggest emailing or calling the folks at BS while you are waiting for Balmar--who are a small shop and MAY just all be at the NYC Boat Show this week, or off for the holiday. BS may have some suggestions about mixing their power with conventional regulators as well. Offhand I'd be terribly reluctant to feed a pulse width DC signal into a conventional regulator's charing sense lead, it just can't be a good thing.