indicates the type of battery and the number of cells the charger is designed to charge.
OPERATION:
Upon installation the charger will charge at its maximum rate and taper to a trickle charge at the battery float voltage.
The desired float voltage may be obtained by adjusting the potentiometer. The battery should then be given a 24 hour
freshening charge by putting the float/equalize switch in the equalizing position to make certain the battery is fully
charged. The unit should then be returned to the float position for normal operation.
AUTOMATIC CHARGE CONTROLS:
The charge rate is completely controlled by the saturable reactor and sensing control. The battery voltage is sensed by a
zener diode. The zener diode conducts into the base of a transistor and the transistor operates to shunt the saturating
coil of the reactor. When the battery is discharged the battery voltage is low and the reactor saturating coil saturates the
reactor The impedance change of the reactor due to the core saturating shifts more voltage to the primary of the
transformer which in turn increases the induced voltage in the secondary of the transformer, thus increasing the charge
rate to maximum rated output. When the battery voltage reaches its float voltage the control begins to operate to reduce
the charge rate. The zener diode begins to conduct into the transistor regulator and begins to shunt the current from the
starting coil of the reactor The reactor begins to de-saturate increasing the impedance, and the voltage to the transformer
primary begins to drop, thus decreasing the output.
A voltage divided across the output terminals of the charger provides the battery reference voltage to the zener diode.
On single potentiometer units a voltage divider is provided with two reference slider-band adjustments. Dual
potentiometer units have separate voltage dividers with one slider band adjustment on the float divider and the other on
the equalizing divider. If the potentiometer does not give the required float or equalizing points the slider bands may be
adjusted to give the required operating voltage.
AC LINE COMPENSATION:
The float charger has a specially designed transformer-reactor combination which inherently compensates for variations
in the incoming AC power. The impedance balance of the transformer-reactor combination compensates for a line
voltage variation of ± 10% of the nominal AC voltage specified on the name plate.
AUTOMATIC CURRENT LIMITING:
The float charger will charge to its maximum current capacity and begin to current limit if overloaded. The automatic
current limiting feature limits the output of the charger to a maximum of 140% rated load. The saturating current resistor
is pre-set and factory adjusted to the required current limiting. The current limiting is accomplished by limiting the
saturating current to the reactor, thus controlling the output of the unit.
AC POWER FAILUIE:
A power failure relay is provided to disconnect the automatic control from the
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