18
S&C Instruction Sheet 712-501
Inspection Recommendations
To ensure Mark VI Circuit-Switcher’s contin ued proper
performance, it should be inspected in accordance with
the recom mended schedule and procedures contained
in the tables in S&C Data Bulletin 712-90, Inspection
Recommendations .
RECOMMENDED INSPECTION PROCEDURES FOR S&C CIRCUIT-SWITCHER COMPONENTS
Component
Inspection Procedures
General
1 . Check with your local S&C Sales Office for any outstanding Field Notifications for inspection, retrofit, or maintenance on
your model switch .
2 . Check the switch for overall cleanliness of the insulators, live parts, and operator . Power washing with water or a
non-abrasive cleaning method should be performed for severe contamination . Reapply lubricant to the live parts after
washing .
Switch Operator
1 . Check for evidence of water ingress, damage, excessive corrosion, or wear .
2 . Check ease of operation during slow, manual cranking using the switch operator manual operating handle .
3 . Check electrical operation, coupled and decoupled .
4 . Check for loose wiring inside enclosure and proper functioning of position-indicating lamps, operation counter, conve-
nience lamp, etc .
5 . Check operation of brake and readjust if necessary .
Power Train
1 . Check for evidence of damage, excessive corrosion, or wear .
2 . Check tightness of fasteners .
3 . Observe operation during slow, manual cranking using the switch operator manual operating handle . Check for complete
stroking of the various drive levers against their stops and for attainment of overtoggle positions, as required .
4 . Check condition of seals .
Interrupter
1
1 . Check for low gas density (indicator underneath interrupter) .
2 . Check tightness of fasteners on current-carrying parts .
3 . Check for discoloration, contamination, or other damage to the interrupter insulation .
4 . Check for excessive corrosion at the terminal pad and interrupter-to-disconnect bus .
5 . Check for evidence of excessive terminal-pad loading .
Charging Motor
1 . Check for evidence of water ingress, damage, excessive corrosion, or wear .
2 . Check tightness of fasteners—especially at the connection between the motor and the interrupter operating shaft .
Disconnect
Live Parts
1 . Check for evidence of damage, excessive corrosion, or wear—especially at the fault-closing contacts and current-carry ing
contacts . Replace current-carrying jaw contacts if the silver-alloy inserts on two or more contact fingers are worn to the
extent that the blade tongue contact engages the full width of the contact finger .
2 . Check tightness of fasteners on current-carrying parts .
3 . Observe operation of disconnect during slow, manual cranking using the switch operator manual operating handle . Check
for proper contact alignment .
4 . Lubricate the contact surfaces with an appropriate lubricant .
2
5 . Check for excessive corrosion at the terminal pad and interrupter-to-disconnect bus .
6 . Check for evidence of excessive terminal-pad loading .
Pre-Insertion Inductor
1 . Clean the exterior of inductor windings using a nontoxic, nonflammable solvent .
2 . Touch up exterior finish of inductor windings with an appropriate silicone-alkyd paint, such as ALMA AP-9753 .
3 . Check moving and stationary arcing rods for proper setting and for evidence of damage and excessive corrosion or wear .
Grounding Switch
1 . Check for evidence of damage, excessive corrosion, or wear—especially at the jaw-contact members .
2 . Check tightness of fasteners on current-carrying parts .
3 . Observe operation using manual operating handle . Check for proper contact alignment .
4 . Lubricate the contact surfaces with an appropriate lubricant .
2
1
Mark VI Circuit-Switcher interrupters should have resistance values
under
200 micro-ohms when new, and
under
500 micro-ohms when in
service . If an interrupter has a resistance value outside this range, contact
your local S&C Sales Office .
2
Shell Gadus® S2 U1000 2 Lubricant, Catalog Number 9999-043 is
available in 1 oz . tubes from S&C . Shell Darina SD2, Dow 33, or equivalent
can be substituted .
Summary of Contents for Mark VI
Page 28: ...Printed in U S A ...
