S&C Instruction Sheet 681-510 9
Operation
Pre-Operation Checks
WARNING
Do not operate this switchgear if the SF
6
-gas
pressure gauge is in the Red zone.
Failure to follow
this precaution can result in a flashover and
equipment damage.
STEP 1.
Make sure that the SF
6
-gas pressure gauge is in
the green zone (or the green and yellow-striped
zone) by lifting the viewing window cover under
way one. See Figure 8.
Note:
If the SF
6
-gas pressure gauge is in the green and
yellow-striped zone, the switchgear can be operated but
the tank must be repaired (if necessary) and refilled with
SF
6
gas as soon as possible.
STEP 2.
Open the viewing window cover and confi rm
the position of the load-interrupter switch or
fault interrupter by visually observing the
position of the blades.
For most Vista switchgear model fault inter-
rupters, confirm the position of the trip flags.
For “-R1” suffix models, confirm the position of
the disconnect switch blade through the viewing
window. See Figures 9 and 10.
Also, inspect the current-carrying components inside
the tank specifically for dislodged hardware, signs of
arcing, and significant blade misalignment.
WARNING
DO NOT operate the energized load interrupter
switch or fault interrupter with dislodged hardware
or obvious signs of arcing or significant blade
misalignment. Equipment damage and personal
injury may result.
Figure 9. Window cover lifts for viewing of switch or fault-
inter rupter blade positions.
Figure 8. SF
6
-gas pressure gauges.
Figure 10. Confirm blade position of load-interrupter switch or
fault interrupter.
WARNING
ALWAYS confirm the position of switches or fault
interrupters by VISUALLY OBSERVING blade
position.
Blade positioning for 15-kV, 12-kA models with
“-R1” suffix
Blade positioning for most Vista models.
Gauge for most Vista
switchgear models.
Gauge for 15-kV, 12.5-kA
models with “-R1” suffix.
TRIP indicator
for three-pole fault interrupt-
ers (can be seen through the
viewing window)
TRIP indicators
for single-pole fault
interrupters
(can be seen through
the viewing window)
