CRISWELL ENGINEERING
Engineering Services
Relaying—Commissioning—Maintenance
Oil Circuit Breakers
Visual and Mechanical Inspection
Remove oil and store in approved containers.
Inspect physical and mechanical condition.
Inspect tie-downs and grounding.
Lower tank(s) and perform internal inspection.
Check for correct oil level in each tank and each
bushing.
Inspect lift rod, interrupters, tank liner, stationary
and moving contacts, dashpots, contact
synchronization between phases, etc.
Check for oil leaks around tanks and bushings.
Filter oil and replace to proper level.
If vented, check that vent mechanism is
unobstructed.
Electrical Test
Inspect all bolted electrical connections for
proper hardware installation and correct
tightness.
Perform a contact-resistance test.
Inspect operating mechanism for loose hardware
or broken parts.
Perform insulation-resistance test at 500 volts dc
on all secondary control wiring, and on all
current transformer and relay circuits.
If operating mechanism is pneumatic, inspect for
air leaks, water in tank, correct compressor
operation, etc.
Perform insulation-resistance test at 5000 volts
dc on primary circuits, phase-to-phase and
phase-to-ground.
Check compressor belt and oil level.
Perform As-Left oil dielectric tests, 3 minimum.
Verify appropriate lubricant on all mechanism
linkages and bearings.
Perform (Doble) watts-loss and Tank Loss Index
(TLI) tests, per Doble procedure.
Check pressure switch settings per
manufacturer’s specifications.
Perform (Doble) insulation power-factor and
capacitance tests on all bushings, per Doble
procedure.
Record As-Found and As-Left counter readings.
Inspect all gaskets and replace if necessary.
Thoroughly clean bushings prior to tests, unless
As-Found and As-Left tests are required.
Internal Inspections
Perform As-Found oil dielectric tests, 3
minimum.
Perform minimum pick-up voltage test on trip
coil.
Verify open, close, and trip-free & anti-pump
operations. Exercise care in performing trip-free
operation if manufacturer advises intentional
delay between close and trip operations.
Perform time and travel analyses tests on
commissioning, and per manufacturer’s
schedule thereafter.
ROY CRISWELL ENGINEERING, LLC
5997 EAST LINDA STREET
ROGERSVILLE, MO 65742
CELL: (417) 860-0964
OFFICE: (417) 886-2445
Proud to be a USA Company
CRISWELL ENGINEERING
Engineering Services
Relaying—Commissioning—Maintenance
High Voltage SF6 Circuit Breakers
Visual and Mechanical Inspection
Electrical Test
Inspect physical and mechanical condition.
Perform a contact-resistance test.
Inspect tie-downs and grounding.
Perform insulation-resistance test at 500 volts dc
on all control wiring, and on all current
transformer and relay circuits.
Inspect and service operating mechanism and
SF6 gas monitoring system in accordance with
manufacturer’s recommendations.
Remove a sample of SF6 gas and test.
Test for gas leaks in accordance with
manufacturer’s procedure.
Perform (Doble) insulation power-factor & wattsloss tests, per Doble procedure.
Verify correct operation of all air (if pneumatic)
and SF6 gas pressure alarms and cutouts.
Perform minimum pick-up voltage test on trip
coil.
Inspect all bolted electrical connections for
proper hardware installation and correct
tightness.
Verify open, close, and trip-free & anti-pump
operations. Exercise care in performing trip-free
operation if manufacturer advises intentional
delay between close and trip operations.
Verify appropriate lubricant on all mechanism
linkages and bearings.
Thoroughly clean bushings prior to tests, unless
As-Found and As-Left tests are required.
Record As-Found and As-Left counter readings.
Trip circuit breaker from each protective device
on commissioning tests, and per manufacturer’s
recommended schedule thereafter.
Perform time and travel analyses tests on
commissioning, and per manufacturer’s
schedule thereafter.
Inspect door gaskets and replace if necessary.
ROY CRISWELL ENGINEERING, LLC
5997 EAST LINDA STREET
ROGERSVILLE, MO 65742
CELL: (417) 860-0964
OFFICE: (417) 886-2445
Proud to be a USA Company
CRISWELL ENGINEERING
Engineering Services
Relaying—Commissioning—Maintenance
SF6 Circuit Switchers
Visual and Mechanical Inspection
Electrical Test
Inspect tie-downs and grounding.
Perform contact-resistance test of interrupters,
and include isolation switches if possible.
Inspect and service operating mechanism and
SF6 gas monitoring system in accordance with
manufacturer’s recommendations.
Verify correct operation of shunt trip coils and
isolation switch sequence.
Perform (Doble) insulation power-factor & wattsloss tests, per Doble procedure.
Test for gas leaks in accordance with
manufacturer’s procedure.
Verify correct operation SF6 gas pressure alarms
and cutouts.
Inspect all bolted electrical connections for
proper hardware installation and correct
tightness.
Perform time and travel analyses tests on
commissioning, and per manufacturer’s
schedule thereafter. Verify synchronization of
isolation switches.
Verify appropriate lubricant on all mechanism
linkages and bearings.
Thoroughly clean insulators and interrupters
prior to tests, unless As-Found and As-Left tests
are required.
Record As-Found and As-Left counter readings.
Inspect overall physical and mechanical
condition.
Verify correct SF6 pressure.
ROY CRISWELL ENGINEERING, LLC
5997 EAST LINDA STREET
ROGERSVILLE, MO 65742
CELL: (417) 860-0964
OFFICE: (417) 886-2445
Proud to be a USA Company
CRISWELL ENGINEERING
Engineering Services
Relaying—Commissioning—Maintenance
Vacuum & Air Puffer Circuit Breakers
Visual and Mechanical Inspection
Electrical Test
Inspect physical and mechanical condition.
Perform a contact-resistance test.
Inspect tie-downs and grounding.
Perform insulation-resistance test at 500 volts dc
on all control wiring, and on all current
transformer and relay circuits.
Inspect auxiliary switches and mechanism
operated contacts.
Check contact erosion visually or by the wipe
test.
Verify correct operation of all air (puffer) tubes
and pistons.
Inspect all bolted electrical connections for
proper hardware installation and correct
tightness.
Verify appropriate lubricant on all mechanism
linkages and bearings.
Thoroughly clean bushings prior to tests, unless
As-Found and As-Left tests are required.
Record As-Found and As-Left counter readings.
Inspect door gaskets and replace if necessary.
Perform a vacuum bottle integrity test at
manufacturer recommended AC voltage.
Perform HVAC Overpotential test on each pole
and across open contacts, arc chutes installed.
Perform minimum pick-up voltage test on trip
coil.
Verify open, close, and trip-free & anti-pump
operations. Exercise care in performing trip-free
operation if manufacturer advises intentional
delay between close and trip operations.
Trip circuit breaker from each protective device
on all commissioning and scheduled
maintenance tests.
Perform benchmark time and travel analyses
tests on commissioning.
ROY CRISWELL ENGINEERING, LLC
5997 EAST LINDA STREET
ROGERSVILLE, MO 65742
CELL: (417) 860-0964
OFFICE: (417) 886-2445
Proud to be a USA Company