Charging Batteries

[CaptainSteven]

I did a week long trip for the first time since upgrading my house bank. 484 amp-hours. It could be that my batteries were never as low as I thought they might be and that's why I did not see the amps go up to 14 during the initial start of charging.

[CaptainSteven]

Update:

Doing some troubleshooting today, I disconnected the battery output wires, turned the battery charger on, as per manufacturers diagnostics. The charger output was 14.6'volts. Reconnecting the wires, it,dropped down to 13.3 volts.

There is high resistance somewhere in the circuit and is downstream irregardless if power is coming from engine or charger.

I will continue on with my search.

[btrayfors]

Originally Posted by CaptainSteven

Update:

Doing some troubleshooting today, I disconnected the battery output wires, turned the battery charger on, as per manufacturers diagnostics. The charger output was 14.6'volts. Reconnecting the wires, it,dropped down to 13.3 volts.

There is high resistance somewhere in the circuit and is downstream irregardless if power is coming from engine or charger.

I will continue on with my search.

Your batteries are the "resistance". How much amperage is flowing?

Try connecting the charger to another battery.

Bill

[CaptainSteven]

I need to trace down where the wires from the charger tie into the system. I don't see a voltage drop comparing output of charger to connections at battery. It's low.

[Scott Berg]

The voltage drops to 13.3 but
at what current? (ohms law and all that)...

I don't think you have a problem except maybe some corroded fittings


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[sailorboy1]

I think maybe you should charge the batteries unless you are answer the "how many amps are the batteries accepting".

Your corroded connections don't answer anything about your original question of why the voltage is different between when using shore power and when using the Honda generator. The only real possible difference between those 2 would be the plug connected to the shore power connection on your boat.

[Scott Berg]

Shore power vs Honda is probably the power factor of the charger
I still want to know the charging current



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[sailorboy1]

For those blaming the PF, just what do you think it would need to be in order to not be able to fully power a 100 amp DC charger? I don't think it matters and people have already posted they can power their charger with a Honda just the same as with shorepower. If it can power a 15 amp AC load it can more than power the charger.

My bet remains that the batteries just aren't charged.

[Ex-Calif]

When on shore power vs. Honda power what is the state of the house loads?

i.e. When at shore do you have the house turned off or reduced (no plotter, autopilot etc?) compared to when underway?

I would isolate the loads for an apples to apples comparison.

[mbianka]

Originally Posted by CaptainSteven

Update:

Doing some troubleshooting today, I disconnected the battery output wires, turned the battery charger on, as per manufacturers diagnostics. The charger output was 14.6'volts. Reconnecting the wires, it,dropped down to 13.3 volts.

There is high resistance somewhere in the circuit and is downstream irregardless if power is coming from engine or charger.

I will continue on with my search.

Still don't think you have a problem. Open circuit voltages you are measuring can be different when the circuits are under load. When you hook up the batteries to the charger they are a load and I would expect they would load down the charger somewhat. As the batteries charge you should see the voltage rise until the charger (assuming you have a somewhat sophisticated charger) is satisfied the batteries are charged and then will drop down to a trickle charge voltage. Perhaps you are measuring a battery that is fully charged and the charger has sensed this and gone into the appropriate mode. What indicators do you have on the charger? You might be looking for a problem where there is none.

[Maine Sail]

Originally Posted by CaptainSteven

Update:

Doing some troubleshooting today, I disconnected the battery output wires, turned the battery charger on, as per manufacturers diagnostics. The charger output was 14.6'volts. Reconnecting the wires, it,dropped down to 13.3 volts.

There is high resistance somewhere in the circuit and is downstream irregardless if power is coming from engine or charger.

I will continue on with my search.

Sounds like normal bulk charging.. Let it charge for a while and the voltage should continue to climb.. With a small charger and large bank it can take a long time to attain absorption voltage.

If the batteries are heavily discharged, and you fire up the charger and the voltage goes to 14.6V quickly, then you have battery issues, as in sulfation. If the batts take current for a while before slowly climbing to absorption voltage they are likely healthy and this is normal bulk charging..