Mitsubishi Electric AE-SW Series Instruction Manual page 35

4.2.5 Accessory devices (General accessory devices)
Inspection item
1.Closing coil (CC)
Shunt trip device (SHT)
2.Auxiliary switch (AX)
3.Motor charging device (MD)
4.Under voltage trip device (UVT)
5.Safety shutter (SST)
6.Cell switch (CL)
7.Mechanical interlock (MI)
4.3 Inspections After a Breaking Operation
Inspect the items detailed for periodic inspection (section 4.2) when the ACB has performed a breaking operation as a result of
an overload current or a short-circuit current.
Reuse is possible if the relevant criteria are satisfied. A circuit must never be reclosed (locally or remotely) before the cause
of the fault has been identified and cleared.
However, it is recommended that the ACB be replaced as soon as possible after it has interrupted a large fault current. The
ACB should be monitored for unusual temperature rises and other abnormalities until replacement occurs. Refer to the follow-
ing chart regarding the level of breaking currents and the treatments to be performed:
Level of breaking current
1.Breaking current is 6 times or less the rated
current (LTD, STD range)
2.Breaking current is 70 percent of the rated
breaking capacity or less (STD, INST range)
3.Breaking current near to the rated breaking
capacity
(Note) 1. In the case of the electronic trip relay with the trip indication function, it can be determined whether the cause of the tripping lies in the
LTD (long-time-delay), STD (short-time-delay) or INST (instantaneous) level.
2. If the magnitude of the fault current cannot be estimated, treat according to 3 of section 4.3.
Inspection method
Electrical operation Must operate reliably and without difficulty
within the operating voltage range indicated in
the "catalog".
Check continuity of AXa Must switch in accordance with the conditions
and AXb. of the ACB.
Electrical operation Must complete the charging reliably and
without difficulty within the designated time
(less than 5sec.) and the operating voltage
range indicated in the "Instruction Manual".
Electrical operation Must be able to close reliably upon application
of a voltage that is 85% of the rated voltage
and to trip and disable closing by the time the
voltage reaches 45% of the rated voltage.
Drawout/Insert operation (1) There must be no breakage of the parts.
(2) Must be able to perform the drawout
/insertion operation without any difficulty.
Drawout/Insert operation Must switch reliably at the "DISCONNECT",
"TEST" and "CONNECT" positions.
Check the gap between 0.2 to 1.2 mm
the trip pin and the lever. (Accessory attachment manual)
Level of ACB damage
(1) Abnormalities of the external parts cannot be
detected visually.
(2) Slight wear of contacts, soiling by soot, etc.
(1) There is slight overall soiling of the exhaust ports
by soot.
(2) There is also overall damage of the contacts and
the arc extinguishing chamber but only to a slight
degree.
(1) There is significant overall soiling of the exhaust
ports by soot.
(2) The contacts and the arc extinguishing chamber
also suffer considerable damage.
Criteria
Please contact our company if there are any
abnormalities.
Please contact our company if there are any
abnormalities.
Please contact our company if there are any
abnormalities.
Please contact our company if there are any
abnormalities.
Please contact our company if there are any
abnormalities.
qRemove any broken parts that impair the
drawout/insertion operation.
wPlease contact our company if the
drawout/insertion operation cannot be
performed.
Please contact our company if there are any
abnormalities.
Please contact our company when cannot
be adjusted.
Reusable.
Refer to section 1.2 regarding the switching
operation lifetime at the rated current.
Reusable.
The breaker can be used if the relevant criteria in
section 4.2 are satisfied.
(1) Immediate replacement is desirable.
(2) If immediate replacement is not possible, the
breaker can be used carefully by gradually
reducing the rated current, etc., provided that the
relevant criteria in section 4.2 are satisfied.
As an additional test, perform the withstand
voltage test to the live parts of the main circuit of
the ACB at twice the rated insulation voltage, in
other words, at 2000 V.
However, replace as soon as possible.
Treatment methods
Treatment
E − 35