Mitsubishi Electric C Series Handling And Maintenance page 66

4 4
4 Spring-charged type (2) 4 4
• Electrical Operation
• Manual Operation:
(a) Precaution to be taken when handling
Every time the electrical operation unit is dismantled or remounted, turn off the mas-
ter circuit-breaker, switch off the operational circuit to make sure that the main and
operational circuits are not live (charged). Beware of electric shock.
Case of remote operation (electric operation)
(i) The operational voltage shall be within the range from 85 to 110% of the rated operational
voltage.
(ii) Since the electric operation unit is of intermittent rating, avoid operating it 10 times or more
continuously (ON and OFF consecutive operation is counted as one operation).
(iii) The turning off by the electric operation requires about 2 sec (from application of OFF signal on
the electric operation unit to turning off of the circuit-breaker). If one wants to open urgently the
main circuit by remote operation, it is recommended to use the circuit-breaker with SHT or UVT.
(iv) When the circuit-breaker trips, the resetting (reclosing) procedure depends on the status of the
electric operation unit before the trips:
Trip with unit ON : Resetting (OFF) operation → ON operation
Trip with unit OFF : On operation → Resetting (OFF) operation → ON operation
Case of local (manual) operation
(i) Turning ON
Pressing the ON button will release the latch mechanism
and turn on the circuit-breaker instantaneously by the en-
ergy of the closing spring.
(ii) Turning OFF (reset)
The manual turning OFF (resetting) should be repeated more
than 10 times after taking out the manual lever. Repeat the
operation of manual lever without fail up until the manual
lever idles. After completion of the manual operation, house
the lever into its original position.
Note. Sometimes the operational load reduces more or
less midway with the circuit-breaker turning off emit-
ting a sound. Never fail to continue to operate the
manual lever until it does idling.
(iii) Trip operation
The circuit-breaker with the electric operation unit has been
so designed that it should not trip even if the trip button is
depressed under OFF condition. When the circuit-breaker is to be tripped on occasion, for
instance, of witnessed test, it shall either be made to trip after once it shall be turned ON or
shall trip by turning it on with trip button depressed.
: When the ON operation switch is closed, the closing coil is excited, latch mechanism
is released and the closing spring will turn on the circuit-breaker instantaneously. If
the OFF operation switch is closed, the relay will come into function to start the motor.
If, under these conditions, the circuit-breaker is turned OFF (reset), the closing spring
will be charged instantaneously.
Depressing the ON button will release the latch mechanism, and the closing
spring will turn on the circuit-breaker instantaneously.
OFF (reset) Operation.
When the manual lever is taken out depressing the leaf spring, and the lever is
thrown a dozen times reciprocatedly, the circuit-breaker turns OFF (resetting)
and the closing spring is charged at the same time.
CAUTION
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