Eaton IZM20, Инструкция по эксплуатации и обслуживанию

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43
10/09 AWB1230-1605
Effective October 2009
Operation and maintenance of
IZM low voltage air circuit breakers
MOELLER www.moeller.net/de/support
Section 6: Inspection and maintenance
General
 Warning
FaiLUrE TO inSPECT, CLEan, anD MainTain CirCUiT BrEakErS
Can rEDUCE EQUiPMEnT LiFE Or CaUSE THE EQUiPMEnT nOT TO
OPEraTE PrOPErLY UnDEr FaULT COnDiTiOnS. THiS COULD rESULT
in EQUiPMEnT DaMagE, BODiLY inJUrY, Or EVEn DEaTH.

CaUTiOn
inSPECTiOn anD MainTEnanCE PrOCEDUrES SHOULD BE CarriED
OUT OnLY BY PErSOnnEL FaMiLiar WiTH THE HaZarDS aSSOCiaTED
WiTH WOrking On POWEr CirCUiT BrEakErS. aDDiTiOnaLLY,
THEY SHOULD BECOME FaMiLiar WiTH THE SPECiFiCS aSSOCiaTED
WiTH TYPE iZM CirCUiT BrEakErS aS PrESEnTED in THiS
inSTrUCTiOn BOOk.
IZM circuit breakers are “top of the line” equipment. This means
they are manufactured under a high degree of quality control, with
the best available materials and with a high degree of tooling for
accuracy and parts interchangeability. Design tests and actual
installation experience show them to have durability well beyond
minimum standards requirements. However, because of the
variability of application conditions and the great dependence
placed upon these circuit breakers for protection and the assurance
of service continuity, inspection and maintenance activities should
take place on a regularly scheduled basis.
Since maintenance of these circuit breakers consists mainly of
keeping them clean, the frequency of scheduled inspection and
maintenance depends to some degree on the cleanliness of the
surroundings. Cleaning and preventive measures are a part of any
good maintenance program. Plant operating and local conditions can
vary to such an extent that the actual schedule should be tailored
to the conditions. When the equipment is subject to a clean and
dry environment, cleaning is not required as frequently as when the
environment is humid with a significant amount of dust and other
foreign matter.
It is recommended that maintenance record sheets be completed
for the equipment. Careful and accurate documentation of all
maintenance activities provides a valuable historical reference
on equipment condition over time.
General cleaning recommendations
Circuit breaker cleaning activities should be a part of an overall
activity that includes the assembly in which the circuit breaker
is installed. Loose dust and dirt can be removed from external
surfaces using an industrial quality vacuum cleaner and/or lint-free
cloth. Unless otherwise indicated, never use high-pressure blowing
air, since dirt or foreign objects can be driven into areas, such as
the breaker mechanism, where additional friction sources could
create problems. Never use a wire brush to clean any part of the
circuit breaker.
Table 11. Inspection Frequency
Breaker Frame Size interval (Breaker Cycles)
a
800A and below 1750
Between 800 and 3200A 500
4000A and above 250
a
Breaker cycle = one no load open/close operation.
When to inspect
Do not wait for specific scheduled periods to visually inspect the
equipment, if there are earlier opportunities. If possible, make a
visual inspection each time a circuit breaker compartment door is
opened, and especially when a circuit breaker is withdrawn on its
compartment extension rails. This preventive measure could help
to avoid future problems.
Industry standards for this type of equipment recommend a general
inspection and lubrication after the number of operations listed in
Table 11 of this section. This should also be conducted at the end of
the first six months of service, if the number of operations has not
been reached.
After the first inspection, inspect at least once a year. If these
recommended inspections show no maintenance requirements, the
period may be extended to a more economical point. Conversely,
if the recommended inspection shows, for instance, a heavy
accumulation of dirt or other foreign matter that might cause
mechanical, insulation, or other electrical damage, the inspection
and maintenance interval should be decreased.
What to inspect
What to inspect and to what extent is dictated by the nature of
the maintenance function. Routine inspections require one type of
observation. Inspections following a known high-level fault require
more detailed inspections.
A drawout type circuit breaker should first be withdrawn from
its compartment onto the compartment’s extension rails. When
the inspection is complete, the circuit breaker can be levered to
the TEST position to check the electrical operations of the circuit
breaker. During the levering out and levering in of the circuit breaker,
be aware for any signs that would indicate that this process is not
working properly.
During the inspection of fixed type circuit breakers, bus systems
supplying the fixed circuit breakers should be de-energized for
convenience and safety.
For functional testing of the trip unit, refer to the separate detailed
instruction book dedicated to the trip unit.
Once the circuit breaker has been cleaned, visually inspect it for any
signs of damage, missing or loose parts, and unusual wear. Be
especially alert for foreign matter that must be removed. On
drawout circuit breakers, inspect the primary disconnect finger
clusters for signs of wear and erosion. Make appropriate
corrections to anything found out of order.
Functional field testing

nOTiCE
BEFOrE DOing anY WOrk On DraWOUT TYPE CirCUiT BrEakErS,
MakE SUrE THE BrEakEr iS LEVErED OUT TO THE TEST Or DiSCOnnECT
POSiTiOn. DUring THE LEVEring OUT anD LEVEring in OF THE CirCUiT
BrEakEr, BE aWarE OF anY SignS THaT WOULD inDiCaTE THaT
THE LEVEring PrOCESS iS nOT WOrking PrOPErLY. iF WOrking On
a FiXED CirCUiT BrEakEr, BUS SYSTEMS SHOULD BE DE-EnErgiZED
FOr COnVEniEnCE anD SaFETY. THE CirCUiT BrEakEr SHOULD BE
SWiTCHED TO THE OFF POSiTiOn anD THE MECHaniSM SPringS
DiSCHargED.
Moeller recommends that the following functional tests be
performed on IZM circuit breakers as part of any maintenance
procedure. The circuit breaker should be removed from service
and Moeller notified if the circuit breaker fails to perform any of
these tests successfully. Please be prepared to provide the number
of operations the circuit breaker has to date as well as the following
nameplate information (see Figure 65 ).