Eaton 360 W-VAC 16, Инструкции по установке, эксплуатации и техническому обслуживанию

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I.B. 3A74791H04
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Effective 7/97
6-9 PRIMARY CIRCUIT RESISTANCE CHECK
Since the main contacts are inside the vacuum cham-
ber, they remain clean and require no maintenance at
any time. Unlike many typical circuit breaker designs,
W-VAC circuit breakers do not have sliding contacts at
the moving stem either. Instead they use a highly reli-
able and unique flexible clamp design that eliminates
the need for lubrication and inspection for wear.
If desired, the DC resistance of the primary circuit may
be measured as follows: close the circuit breaker, pass
at least 100 amps DC current through the circuit break-
er. With a low resistance instrument, measure resis-
tance across the studs on the circuit breaker for each
pole. The resistance should not exceed the values
shown in Table 6.3.
6-10 MECHANISM CHECK
Make a careful visual inspection of the mechanism for
any loose parts such as bolts, nuts, pins and rings.
Check for excessive wear or damage to the circuit
breaker components. Operate the circuit breaker sever-
al times manually and electrically. Check the closing
and opening times to verify that they are in accordance
with the limits in Table 5.1.
6-11 LUBRICATION
All parts that require lubrication have been lubricated
during the assembly with molybdenum disulphide
grease (Cutler-Hammer Material No. 53701QB). Over a
period of time, this lubricant may be pushed out of the
way or degrade. Proper lubrication at regular intervals is
essential for maintaining the reliable performance of the
mechanism. Once a year or every 500 operations
whichever comes first, the circuit breaker should be
relubricated. The locations shown in Figure 6-1 should
be lubricated with a drop of light machine oil.
After lubrication, operate the circuit breaker several
times manually and electrically.
Roller bearings are used on the pole shaft, the cam
shaft, the main link and the motor eccentric. These
bearings are packed at the factory with a top grade slow
oxidizing grease which normally should be effective for
many years. They should not be disturbed unless there
Figure 6-4 Side View of Loading Spring Indicator
(Circuit Breaker Closed)
Figure 6-5 Graphical Representation of Contact Wipe
Measurement of Loading Spring Indicator (Circuit
Breaker Closed)
31mm 23mm
CONTACT WIPE