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Instruction Book IB019009EN November 2017 www.eaton.com
AK-2-25, AK-2A-25, & AK-3A-25 LV-VSR
Breaker-To-Motor Starter Conversion
SECTION 6: INSPECTION AND
MAINTENANCE
6.1 INTRODUCTION
WARNING
•
DO NOT WORK ON A LV-VSR IN THE ‘CONNECT’ POSITION.
•
DO NOT WORK ON A LV-VSR WITH SECONDARY DISCONNECTS
ENGAGED.
•
DO NOT WORK ON A LV-VSR WITH THE CONTACTOR CLOSED.
•
DO NOT DEFEAT ANY SAFETY INTERLOCKS.
•
FOLLOW ALL PRECAUTIONARY MEASURES WHEN TESTING FOR
VACUUM INTEGRITY.
•
FAILURE TO FOLLOW ANY OF THESE INSTRUCTIONS MAY CAUSE
DEATH, SERIOUS BODILY INJURY, OR PROPERTY DAMAGE. SEE SECTION
2 - SAFE PRACTICES FOR MORE INFORMATION.
6.2 FREQUENCY OF INSPECTION
Inspect the LV-VSR once a year when operating in a clean, non-
corrosive environment. For a dusty and/or corrosive environment,
inspection should be performed twice a year. Additionally, it is
recommended to inspect the LV-VSR every time it interrupts fault
current.
The no-load life test value of the LV-VSR is hundreds of thousands
of operations. This value will be reduced if proper inspection,
maintenance, and cleaning is not performed.
Refer to Section 6.3 for maintenance and inspection check points.
6.3 INSPECTION & MAINTENANCE PROCEDURES
Inspection and maintenance procedures are recommended to be
performed outside of the cell.
CAUTION
SOME COMMERCIAL CLEANING AGENTS WILL DAMAGE THE
NAMEPLATES OR MOLDED PARTS. MAKE SURE THAT CLEANING AGENTS
OR SOLVENTS USED ARE SUITABLE FOR THE JOB.
6.3.1 V201 CONTACTOR
NOTICE
THERE ARE NO FIELD SERVICEABLE PARTS ON CONTACTORS.
WARNING
THE ONLY WAY TO CLOSE THE CONTACTOR IS TO ENERGIZE THE COIL.
IF THE COIL IS ENERGIZED FOR THIS OR OTHER MAINTENANCE, USE
ADEQUATE CARE TO GUARD AGAINST ELECTRICAL SHOCK.
6.3.2 CONTACT WEAR ALLOWANCE
Contact material vaporizes from the contact faces during every
interruption and condenses inside the bottle. This is normal and is
provided for by over-travel or wear allowance. When the contactor
is fully closed, there is a gap between the pivot plate and the
bottle nuts. As the contacts wear, this gap decreases. When any
gap goes below 0.020 inches, the unit should be replaced. Use
the 0.020 inch thick fork shaped over-travel gauge supplied for this
measurement, Part Number 7874A59H01. Figure 6-1.
WARNING
DO NOT READJUST THE BOTTLE NUTS TO RESET OVER-TRAVEL AS THE
BOTTLES WEAR. ONCE PLACED INTO SERVICE, OVER-TRAVEL SHOULD BE
CHECKED BUT NOT ADJUSTED.
6.3.3 MECHANICAL CHECKS
WARNING
THE MECHANICAL CHECKS MAY ONLY BE PERFORMED OUTSIDE THE
SWITCHGEAR CELL.
Use a test cabinet to operate LV-VSR. Operate the appropriate push
buttons to close and open the contactor. While the contactor is
closed, observe the over-travel gap between the pivot plates on the
crossbar and the bottle nut on each pole. This over-travel gap should
be no less than 0.045 inch when the contactor is new. If less, refer
to Contact Wear Allowance section of this manual.
While the contactor is open, attempt to pull the armature forward.
The armature should not move because it should already be firmly
against the plastic main frame. If it does move, refer to Kickout
Spring Adjustment section in this manual.
6.3.4 KICKOUT SPRING ADJUSTMENT
The kickout spring is not disturbed by any maintenance described in
this manual, and should not need any adjustment. However, when
the contactor is in the open position, the crossbar should be solidly
against the frame, so that it cannot move any further open even
when pulled. If kickout spring is out of adjustment, call your closest
Eaton representative.
Figure 6.1. Over-Travel Gauge