Control Wiring; Primary Circuit - ABB ADVAC Installation And Operation Manual

Medium voltage vacuum circuit breaker
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C
W
:
ONTROL
IRING
The control wiring requires visual inspection of hardware, low-frequency withstand voltage testing and 2-5 manual
operations during routine maintenance. Disconnect control power before verifying secondary hardware and before low-
frequency withstand voltage testing.
Remove the front cover with a screwdriver. Correct any loose or missing mounting hardware. Verify the ground wire
connection to the frame and all connectors' alignment and snugness on the electrical components. Visually inspect the
secondary plug and correct any pins that may have become displaced.
To verify the integrity of the secondary insulation, perform the following low-frequency withstand voltage test:
1. Connect all pins from the secondary to a test wire
2. Connect test wire to the high potential lead of the test machine
3. Ground the breaker frame
4. Start machine with output potential at 0 (zero) VAC RMS.
5. Increase the potential to the required insulation test voltage (1125VAC RMS)
6. Hold for one minute
7. Reduce potential to 0 (zero) VAC and turn off machine
A successful withstand indicates satisfactory insulation strength of the secondary circuit. Failing insulation will not
sustain the voltage across the secondary. Replace the breaker control wiring if the insulation fails during low-frequency
withstand voltage testing.
Replace the front cover before operation. Verify the operation with 2-5 electrical operations in the Test position or with a
remote power supply.
The internal shield of a vacuum interrupter can acquire an electric charge which CAN BE
retained even after the voltage is removed. Discharge the mid-band ring with a grounding
stick before working on any part of the circuit breaker.
P
C
A
RIMARY
IRCUIT
The primary circuit requires visual inspection of hardware, low-frequency withstand voltage testing and lubrication during
routine maintenance.
All insulation material should be clean and free of structural cracks. Some minor cracks are inherent in the insulation
material. Inspect for structural cracks and replace damaged parts.
Dirt or dust may create a dielectric path to ground on the insulation. Remove dust and dirt with a clean, lint-free cloth.
Apply distilled water to the cloth to remove any difficult dirt. DO NOT return the breaker into service until the insulation
surfaces are completely dry.
Lubrication on the primary contacts should be inspected during routine maintenance. Use NO-OX-ID special grade-A
grease for the lubrication of primary contacts (ABB No. 713222A, 1 Pt. can).
28
MAINTENANCE
:
SSEMBLY
(Pole)
1VAL050503-MB Rev B Replaces (1VAL057485-MB Rev. C) Oct 2013
DANGER

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