Trace Engineering DR Series User Manual

Trace Engineering DR Series Owner’s Manual - Version 3.2 - 9/7/98 - Page 10
Three Stage Battery Charging
The battery charger in the Trace DR series inverters, charges in three stages - BULK, ABSORPTION,
and FLOAT - to provide rapid and complete charge cycles without undue battery gassing. A manually
operated equalize stage is provided for periodic battery maintenance. The time diagram at the bottom
of this page shows how DC voltage and AC current change with time through the different charge
stages.
Stage One - Constant Current (Bulk Charge)
This stage is initiated when AC is applied to the AC input of the inverter, and is terminated when the
batteries reach the BULK CHARGE VOLTAGE. During this stage the Charger LED glows steady
orange.
Stage one charges the batteries at a constant current. The level of charge for this phase is set using
the BATTERY CHARGER RATE control on the front panel.
Stage Two - Constant Voltage (Absorption Charge)
Absorption is initiated when the Bulk Voltage setting is reached. At this point the charge current begins
to taper off at whatever rate is required to hold the voltage constant. During this stage the Charger
LED blinks orange. The absorption charge phase is terminated in one of two ways.
1. Normally, as the charge cycle progresses, the current required to hold the battery voltage
constant gradually reduces. When this current equals the programmed return amps setting
(battery bank capacity/40), the voltage is allowed to fall to the FLOAT (float voltage) setting -
stage three.
2. If there are DC loads on the batteries, the current may never fall to a level low enough to
initiate the float voltage stage. A timer is used to ensure that the battery voltage does not
remain indefinitely at the Bulk Charge Voltage. The timing circuit is activated by the onset of
stage two, it terminates stage two if the charge current does not reach the return amps value
setting within 12 hours.
Stage Three - Maintenance Voltage (Float Charge)
The charger remains in the float stage until the unit is turned off or loses AC input power (i.e. generator
or grid). During this stage the Charger LED glows steady green. The purpose of stage three is to
maintain the batteries at a voltage that will hold full charge but not gas the batteries.
Note: When DC loads are placed on the battery, the charger will deliver currents up to the Maximum
Charge Rate setting while maintaining the float voltage.
Bulk Charge Absorption Charge Float Charge
DC Voltage
AC Current
Constant Current
Constant Voltage
Reduced Current and Voltage
Bulk Volts Setting
Float Volts Setting
Time
Battery Charge
Rate
Absorption Time
Charging
Starte
d
3- Stage Battery Charger
DC Voltage and AC current
Charge Profile

Trace Engineering DR Series Specifications

General

Brand	Trace Engineering
Model	DR Series
Category	Inverter
Language	English