Another Golf Cart Battery Question

boulderado wrote:
I decided to reach out to WFCO to get there take. For what it's worth, here is there reply:

The charge algorithm is automated, but it is a 3 stage charger.
Secondarily, the converter does not pump amperage into the battery, but rather the battery draws from the converter. So, the charge rate is constantly variable, based on what the battery or 12v loads require. There is no issue using this converter with golf cart batteries.

I see there is a PowerMax direct replacement for the WFCO 8955, running about $140 on Amazon. I guess that might be worth it based on feedback from the forum.

what they don't tell you is HOW the charger determines if it should go into bulk mode charging. Here is what it does
a) stuffs max current into the battery
b) THEN looks at the voltage AT THE WFCO output, not the battery terminals.
C) if that voltage is below the threshold it stays in bulk mode.

The problem is that even with short cables once the battery sees the 45A or so battery voltage + cable drop is almost always guaranteed to have the charger think the battery is charged enough to set the voltage to around 13.6-13.8 which won't give you more than about 15A or so even on a pretty deeply discharged battery.

PD and others FIRST look at the battery terminal voltage, if it is below the threshold it goes to bulk mode charging and stays there till battery voltage rises enough.

And, you can always set the PD to go into bulk mode charging regardless of battery state of charge to kick the charger into fast charging mode.

WFCO doesn't have this option.

They are correct, you can use the WFCO with GC2 batteries and any FLA battery. Problem is few if any folks have been able to get it into bulk charging mode, and get a battery fully charged.

And a GC2 battery typically has higher internal resistance than a 12V "marine" battery. That also means terminal voltage with high current input is higher than with a typical 12V, even more likely not to go to bulk charging mode.

At one time I did an experiment with the WFCO I took out of my trailer.
A pair of almost new GC2's I had discharged to below 50%
2ft of #4 welding cable to the WFCO (about the largest diameter wire you can use with the WFCO)
plugged in the WFCO to see what it would do. 45A for a few minutes, then voltage dropped to 13.8 and 15A, so it went into bulk mode for only a few minutes. And at 15A it would take about 8 hours to get anywhere near full charge.
Same setup with a PD60A charger but with about 10ft of #4 and it went to 50A for over and hour before it started to taper and the batteries were at 90% in less than 2 hours.