Siemens 3AH35-SE Series, Инструкция по эксплуатации

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31
Checks of the spring-charging motor (88)
No additional checks of the spring-charging
motor are necessary. If it is necessary to
remove or replace the spring-charging motor,
torque motor-mounting hardware to
7.3-8 ft-lb (10-11 Nm).
Anti-pump relay
If it is necessary to remove the connections to
the anti-pump relay, use care to avoid
damaging the relay. Replace the relay if the
relay terminals are damaged or loose in the
relay body.
Vacuum interrupters
The life expectancy of vacuum interrupters is
a function of the numbers of interruptions
and magnitude of current interrupted (refer
to Table 3: Typical vacuum interrupter contact
life expectancy on page 29 and Figure 18:
Typical vacuum interrupter contact life curves
on page 30).
The vacuum interrupters must be replaced
before the number of mechanical operations
(listed in Table 2) are reached, or when the
contacts have been eroded beyond allowed
limits. Vacuum interrupter replacement
procedures are detailed in the following
maintenance instructions.
The vacuum interrupter contact life curves
(refer to Figure 18: Typical vacuum interrupter
contact life curves on page 30) are offered as
a guide to expected life.
Vacuum-integrity check (using
mechanical test) (refer to Figure 19:
Manual check of vacuum integrity on
page 34)
Before putting the circuit breaker into service,
or if a vacuum interrupter is suspected of
leaking as a result of mechanical damage,
check the vacuum integrity either
mechanically as described in this section, or
alternatively, electrically using a high-
potential test set as described in the next
section.
Open and isolate the circuit breaker and
detach the insulating coupler (48.0) from
lever (48.6).
The atmospheric pressure will force the
moving contact of a hermetically sealed
vacuum interrupter into the closed position,
causing lever (48.6) to move into the position
shown in Figure 19: Manual check of vacuum
integrity on page 34).
A vacuum interrupter may be assumed to be
intact if it shows the following characteristics:
1. An appreciable closing force has to be
overcome when lever (48.6) is moved to
the open position by hand;
2. When the lever is released, it must
automatically return to the closed position
with an audible sound as the contacts
touch.
After checking the vacuum, reconnect the
lever (48.6) to the insulating coupler (48.0).
High-potential tests employ hazardous voltages.
Will cause death and serious injury.
Follow safe procedures, exclude unnecessary personnel and use safety
barriers. Keep away from the circuit breaker during application of test
voltages.