Rockwell Automation 140U Q and M-Frame Circuit Breakers Installation of Q-Frame Circuit Breakers - Manual (Page 5)

PUSH-TO-TRIP
I 1 Magnetic
Trip
Unit
Magnetic - Amps Cat.
Multiples of In. No.
Page 5
Fig. 4-2 Unit Magnetic Adjustment Buttons
WARNING
CONTACT WITH ENERGIZED EQUIPMENT CAN
RESULT IN DEATH, SEVERE PERSONAL INJURY,
OR
SUBSTANTIAL PROPERTY DAMAGE. DO NOT
NANCE ON EQUIPMENT WHILE IT IS ENERGIZED.
ALWAYS VERIFY THAT NO VOLTAGE IS PRESENT
BEFORE PROCEEDING WITH THE TASK, AND
ALWAYS FOLLOW GENERALLY ACCEPTED SAFETY
PROCEDURES.
ATTEMPT TO INSTALL OR PERFORM MAINTE-
Note: When replacing an existing circuit breaker of
the types listed above, make sure the voltage,
continuous current, and interrupting rating of the
new circuit breaker are suitable.
4. MANUAL OPERATION, AND
MAGNETIC TRIP UNIT ADJUSTMENT
Manual Operation
Manual operation of the circuit breaker is controlled by
the circuit breaker handle and the PUSH-TO-TRIP button
in the trip unit. The circuit breaker handle has three posi-
tions, two of which are shown on the cover with raised let-
tering to indicate
ON and OFF. On the handle, ON, OFF,
and trip are also shown by a color-coded strip for each
circuit breaker handle position: red for
ON, white for
tripped, and green for OFF (see Fig. 4-1).
Circuit Breaker Reset
After a trip operation, the circuit breaker is reset by mov-
ing the circuit breaker handle to the Reset (extreme OFF)
position.
Note: In the event of a thermal (overload) trip the
circuit breaker cannot be reset immediately. In a
breaker with a thermal-magnetic type trip unit the
thermal element needs to cool (up to approximately
five minutes) before it can be reset. A circuit breaker
with a electronic RMS trip
unit simulates the thermal
element with an electronic “thermal memory” that
also requires
up to five minutes to “cool” before it
can be re-energized.
No circuit breaker should be until the cause
of trip is known and the situation rectified.
PUSH-TO-TRIP Button
The PUSH-TO-TRIP button operates the circuit breaker
tripping function and may be used to periodically exercise
the operating mechanism. In thermal-magnetic trip units,
the button is designed to be operated by a small screw-
driver. The rating plug in electronic RMS trip units con-
tains the PUSH-TO-TRIP button which is operated by
finger pressure. There is no PUSH-TO-TRIP button in the
molded case switch.
Thermal-Magnetic Trip Unit Adjustment
The magnetic element of each pole of the trip unit can be
adjusted by rotating the adjustment buttons on the front
face of the trip unit with a screwdriver. The buttons have
several settings as indicated on the nameplate with
40752-078(1) Effective 5/02