Negative Voltage on Cart Frame

[CRK]

Could it be that 61 volts is not fully charged? and that is why the charge is not turning off?

[Speedchaser]

Batteries will hit about 65 volts at end of charge cycle, and the charger should turn off on its own.

[rib33024]

Originally Posted by Speedchaser

Batteries will hit about 65 volts at end of charge cycle, and the charger should turn off on its own.

This is true, but it can get as high as 67 Volts before it turns off




59V may fully charge a 48V battery pack.
The voltage it takes to fully charge a 48V battery pack depends on who manufactured the batteries in the pack as well as their age and condition.

By definition, a lead-acid wet cell is fully charged when the specific gravity of the electrolyte ceases to increase while a charging current is passing through it. Since open-circuit voltage increases/decreases as the electrolyte's specific gravity increases/decreases, open-circuit voltage is an indirect or secondary means of monitoring the electrolyte's specific gravity and is often used to do so.

An ideal charger would monitor pack voltage and when it ceased to rise over a predetermined period of time, it would stop the regular charging mode and go into a float charge mode, however few, if any, chargers typically used by golf cart owners are ideal. Most of them simply shut off at a predetermined voltage that is high enough to almost fully charge most battery packs without being so high that repeated use would significantly harm battery packs that are fully charged at the lower end of the typical voltage spectrum needed to fully charge a battery as determined by empirical data.

Here is Trojan's recommended charge curve for a single (2V) deep cycle wet cell. There are 24 cells in a 48V battery pack, so do the math and you get 58.80V to 66.96V. However, Trojan uses an electrolyte that is 27.7% sulfuric acid by weight (SG = 1.277) and other battery manufacturers use different concentrations, so the on-charge voltage that is typically reached when their batteries are fully charged, will be higher or lower.
quote johnnieB

[Stevegrmich]

. . . and charge cycle can take up to 16 hours to complete . .