INSTALLATION, OPERATING AND TROUBLESHOOTING INSTRUCTIONS FOR MODEL E12
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AUTOMATIC CHARGE CONTROLS (TYPE AC41)
The charge rate is completely controlled by the saturable reactor and sensing control (AC41). The
battery voltage is sensed by the AC41 Control Panel. An op-amp 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 it float voltage, the control begins to operate
to reduce the charge rate. The op-amp begins to conduct into the transistor and begins to shunt the
current from the saturating coil to 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.
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 nameplate.
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 105% rated load.
The control panel is preset and factory adjusted to the required current limiting. The current limiting is
accomplished by limiting the saturating current to the reactor, thus, controlling the maximum current
output of the unit.
AC POWER FAILURE
A power failure relay is provided to disconnect the automatic control from the battery and, therefore,
limit the drain on the battery. One (1) set of normally open and closed contacts from this relay is
connected to terminals for connection to a remote power failure alarm. The charger will automatically
resume charging upon return of AC power.
ADJUSTMENTS/MAINTENANCE
The charger is factory tested and preset so that no field adjustments are necessary. Potentiometers are
provided for adjusting the float and equalizing voltages to the required levels. Because of the stable,
rugged, and static design of this unit, very little maintenance is required. Occasional blowing out of dust
and tightening of connections are the only maintenance requirements.
Float / Equalize lights indicate the charge mode of the rectifier.
FILTERING E12 UNITS
Additional filtering is provided on E12 units. Standard filtering is 100 MV-RMS when connected to a
battery with an amp hour capacity of four (4) times the capacity of the charger at rated output.
