Charger switch question >>>


Member III
There is a switch to choose on face of charger:
A) bulk absorption/float or
B) maintain 13.5V

Which? Seems either would suffice?? Had been set for "B" by P.O. perhaps for years and no problem thus far. 2/Group 26 flooded batteries.

Older Zentrex 20 amp. charger.

Tom Metzger

Sustaining Partner
B is fine if you don't recharge at the dock from a deep discharge. Charging will take a VERY long time. When working at a utility we only used float charging for our station battery banks - 48 to 230 VDC. We did maintain them regularly, reading each cell voltage, etc, and equalized when necessary to avoid cell reversing. That's a problem we don't have with 12 volt batteries.

A is what is normally used by sailors to provide faster charging.

The charger should also be adjusted for the battery's temperature. There is a switch on your charger for that if you use A.
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Member III
A = Three stage charge, the Full Monty

(correction to the data on this site, don't charge Gel over 14.1 volts, per abyc)

B = Trickle charge, or basically a float charge without bulk and absorption
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