Charging Current

[Bill Balme]

This morning my batteries were at 12.0 V - the monitor saying about 55% capacity, so I started the engine to do some charging...
I have a Balmar 100A alternator and a Balmar 'Max Charge MC-614' regulator.

The Battery charge light on the engine controls is flashing and I'm only getting 35A out of the charger - right from the get-go. I would have expected to get 70 or 80 at least.

Any idea where I look first to sort this out?

Appreciate your assistance...

[btrayfors]

Bill,

As usual, the first thing to check is the connections....all of them. Be sure they're clean and tight.

You didn't say what type of batteries you have, total AH capacity, or their age/condition, etc. If flooded, be sure all have appropriate water levels and, again, check all connections to be sure they're clean and tight.

Check the belt on the engine as well to be sure it's tight. And, check the connections on the MC-614, including the fuse.

Bill T

[Bill Balme]

OK - It gets stranger... After running for 20 minutes, the charging light on the engine has stopped flashing and the current is now up to 55A... I really don't know where to look now!

[btrayfors]

Connections, connections, connections. :-)

Don't just look at them. Remove and clean them. Check connectors as well on battery cables, sense wires, regulator, alternator, etc., etc.

It's a pain in the neck, but needs to be done.

Bill

[Bill Balme]

Have to say I agree with you. Reeks of bad connections. Thanks!

[thomm225]

Originally Posted by btrayfors

Connections, connections, connections. :-)

Don't just look at them. Remove and clean them. Check connectors as well on battery cables, sense wires, regulator, alternator, etc., etc.

It's a pain in the neck, but needs to be done.

Bill

This was the problem with mine just last Monday. My charger wouldn't show a charge at all. (mine has lights only to show charging)

My autopilot kept going nutty. First I replaced the $12.00 controller that has been in use for 3 years. No change.

Then disconnected one of the two batteries and came in.

Now both batteries have charged back up to 14.4 volts when connected to solar so it was the connections as usual. I hadn't cleaned them this year

[GordMay]

Refer to Figure 7 for common system conditions that may initiate an alarm. When in the alarm mode, the 3-digit numeric display will indicate the
exact cause for the alarm in Long Display. Specific advisory codes are shown in Figure 17.

See also: VIII. SYSTEM TROUBLESHOOTING (Pages 8 & 9)

➥ http://www.balmar.net/wp-content/upl...l-pre-2005.pdf

[smac999]

what rpm? don't idle it. you should be at 1500rpm+ for alt output.

check alt output voltage at alt, and battery voltage at battery, and field voltage at alternator. and battery voltage sense wire at regulator. with a volt meter. all under the same conditions. (secs apart)

also tell us size of alt cable and lengh. and how it is wired and how the charge is shared.

[mickt243]

+1 to what smac said....

BUT

was that 12.0 volts under any kind of load, or at no load, or at no load and rested at no load for some time?

if the measured voltage was under load, then yes, your batteries are somewhere "about" 50% state of charge...... which for flooded cell batteries is as low as you should discharge them with any regularity, and they should never be left in that state... so good on you for trying to charge them....

if the voltage was at no load (or very low load) , or worse, no load and rested for some time, then your batteries are "about" 100% discharged, and should never have been drawn down this far (except in emergency, bilge pumps spring to mind).... in this state, the lead suplhate created by discharging begins to change form greatly increasing the batteries resistance to charging.... bear in mind that to limit your charging current to 35A, a TOTAL system resistance is 0.068ohms - that is why everyone is telling you to check connections, one dodgy connection could easily increase the resistance by that much, or more.... if it is over discharged, that might explain the initial resistance to charge, and you might have just caught it in time to save the battery from permanent damage.

to elaborate a little more on what smac said - in your car, the alt will not put out its reted amps until the engine is spinning at 3000 rpm or more (at which point the alt is doing ~8K rpm...).... on your boat, the pullies will be different ratios, but the idea is the same, at idle, the alt may not charge at all, it will need to be well above idle speed to do any meaningful charging.

then there are the vagaries of how batteries charge, and how charge current tends to taper off over time - to get 200Amp hours back into your 400AH bank, will probably take 6-8 hours of engine time at speeds well above idle - and this is without consideration to any load you may have (fridge, lights, radios etc...)

[donradcliffe]

RTFM

http://www.balmar.net/wp-content/upl...S-MC-614-H.pdf

Set the 614 for the short display, and write down the results with the engine running. Pay particular attention to the battery voltage (that the 614 thinks it sees), and the target voltage. If that doesn't get you on the right path, write down the short and long display results and report back with them.

[mickt243]

yeah, well reading that, OP's fancy-schmancy regulator might just be working as advertised....... or might require a bit of a closer look RE setup....