CBPS-300 OPERATING INSTRUCTIONS
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1.0 INTRODUCTION
1.1 General Description
Vanguard Instruments Company produces
the CBPS-300 as a microprocessor-
controlled circuit breaker DC power supply.
This device was designed to replace the
substation batteries during circuit breaker
testing.
The CBPS provides a ripple free, DC power
source to operate utility circuit breakers for
contact-timing and other breaker operations.
The CBPS-300 allows the user to operate
the OPEN and CLOSE coils of a circuit
breaker during tests under different
selectable operating conditions such as full
voltage or minimum voltage operations.
External trigger input allows the CBPS-300
to be used with the Vanguard Instruments
circuit breaker timers.
A separate DC supply is also available to
drive the breaker mechanism charging
motor.
All CBPS-300 supply outputs are over
current and short circuit protected. This
feature protects the CBPS-300 power-
supplies and eliminates the use of
conventional fuses or circuit breaker
protection circuitry.
The CBPS-300 test voltage is selectable
from 24Vdc to 250Vdc. The voltage control
knob on the CBPS-300 front panel allows
the operators to select test voltages.
Coil or charging motor voltage reading is
displayed on a 2 line by 16-character back lit
LCD screen. Push button switches marked
OPEN, CLOSE and MOTOR are used to
operate the breaker’s respected coils and
charging motor
1.2 Functional Description
The CBPS-300 is a variable voltage DC
power supply designed specifically to
perform maintenance test on circuit
breakers. The CBPS-300 DC voltage is
selectable for 24Vdc to 250Vdc. Its ripple
free DC output voltage is regulated up to 2%
voltage variation under-load; making it an
ideal device for testing circuit breaker coils
under different operating voltages.
A built-in initiate circuit allows the user to
OPEN or CLOSE breakers from the CBPS-
300 control panel.
The CBPS-300 will energize the breaker trip
or close coil for one-second duration. This
initiate circuit is over current and short
circuit protected. Reset key on the front
panel allows the user to clear the fault
condition.
An unfiltered DC supply is also available to
drive the breaker mechanism charging
motor.
A voltage control knob allows the user to set
coil or motor test DC voltage. DC voltage
output is shown on the 2 lines by 16
characters back-lighted LCD.
1.3 Furnished Accessories
The CBPS-300 is shipped with six 10-foot
test cables with “quick disconnect” type test
plugs on the unit end, and alligator clips at
the test load end. The following cables shall
also be included with the CBPS-300: One
power cord, One ground cable and a cable-
carrying bag.
Summary of Contents for CBPS-300
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