Murphy BCEG-24-20 - Manual (Page 8)

Section 75 00-02-0615
02-29-08 - 4 -
General Product Information
Please read the following information before installing. A visual inspection of this product for
damage during shipping is recommended before installation. It is your responsibility to ensure
that qualified mechanical and electrical technicians install this product.
The Guardian charger provides automatic, current limited and voltage controlled charging of
vented lead acid batteries. It may be used in a wide range of industrial charging applications,
including batteries for standby engines, pumps and generators.
This charger is designed for connection to only one battery. Do not use more than one charger
per battery, or more than one battery per charger.
The charger is supplied in an enclosed stainless steel panel suitable for wall mounting.
NOTE: In event of no AC supply to charger, the voltmeter will display the DC
voltage of any connected DC equipment.
Each unit consists of a transformer, rectifier and thyristor control circuit. The control circuit
ensures that the charger maintains a battery voltage at the pre-calibrated float level, while
supplying any additional load current up to the specified maximum.
Auto Boost (Equalizing) Operation
Auto boost operation provides an increased output voltage when batteries are below a preset
point. Once the batteries have reached the boost voltage the charger reverts to its float
voltage. This operation equalizes the batteries, maximizing battery life and capacity.
Boost Initiate Operation
The boost initiate switch forces the charger to enter an auto boost cycle even if battery voltage
is above the preset point. Once this operation is completed the charger returns to it’s float
voltage.
Temperature Compensation
The remote temperature compensation provides control of the output voltage based upon
temperature. As temperature increases the charging voltage is decreased at a negative
coefficient of 3mV/
°F/Cell.
Charge Fail and Alarms
A self diagnosis ‘charge fail’ circuit and relay output is provided along with under and over
voltage warnings. The dry contact relay outputs de-energize in the event of a charging fault or
high/low battery state.
Electrical connection of the AC supply and DC output and alarms are via spring-clamp
terminals.