Siemens Low Voltage Power Circuit Breaker WLL2S320

DANGER: Hazardous voltage. Will cause death, serious personal injury, or equipment/property damage. Turn off and lock out all power supplying this device before working on this device.

Only qualified personnel should work on this equipment, after becoming thoroughly familiar with all warnings, safety notices, and maintenance procedures contained herein and on the devices.

WARNING: High speed moving parts. Can cause serious personal injury. Discharge the closing spring before inspection and before carrying out any work on the circuit breaker.

Is the worker trained and authorized to energize, de-energize, clear, ground and label circuits and equipment in accordance with established safety practices?

Is the worker trained in the proper care and use of protective equipment in accordance with established safety practices?

Is the worker trained in administering first aid?

The WL circuit breaker is designed and constructed to the highest standard of quality, using the best materials available. Design tests and experience have shown that the circuit breakers can withstand and perform greater than the minimum requirements of the associated design and performance standards.

Contact assemblies need to be changed depending on their condition, but no later than - 12,500 operations in FS II up to 1600 A; (3- and 4-pole) - 10,000 operations in FS II 3200 A; (3- and 4-pole) - 10,000 operations in FS III; (3- and 4-pole)

Number of operations performed by the circuit breaker

Charge closing spring of circuit breakers to be interlocked (page 6-4)

Test the various possibilities of the planned interlocking configuration one after the other

Re-adjust Bowden cables if necessary

Discharge the closing spring of the circuit breakers to be interlocked (page 23-2)

Note: The following maintenance points must be followed:

1 The adjustment of the Bowden cables needs to be checked after the first 100 switching operations and must be readjusted if necessary.

2 The adjustment of the interlocking device needs to be checked and, if necessary, readjusted every 1000 operations or at least once every year.

3 During the inspection, the Bowden cables have to be checked against kinks and abrasions, split wires of the exposed steel cable, damage to the cable housing and the adjustment unit (tube setting with thread and nut) and have to be readjusted if necessary. In addition, the movability of movable parts of the interlocking device in their bearings needs to be examined.

DANGER: Hazardous voltage. Will cause death, serious personal injury, or equipment damage. Turn off and lock out all power supplying this device before working on this device.

WARNING: High speed moving parts. Can cause serious personal injury. Discharge the closing spring before inspection and before carrying out any work on the circuit breaker.

Circuit breaker opened and closing spring discharged

Circuit breaker moved into the withdrawn position in the cradle

Arc splitter plates inspected for erosion

Arc splitter plates inspected for soot

Arc splitter plates inspected for spots of collections of molten metal

Is there heavy wear on the arc splitter plates?

If there is heavy wear, replace the circuit breaker.

DANGER: Hazardous voltage. Will cause death, serious personal injury, or equipment damage. Turn off and lock out all power supplying this device before working on this device.

Powder-coated inner sides of the covers not burned

No damage on the inner side of the cover

Upload a photo of the arc chute cover

Sign off on the arc chute cover inspection

Warning: Mishandling may lead to broken insulation plates of the arc chute housing, and compromised insulation capacity.

Loosen screw by approx. 15 mm; do not remove it; FS III and FS II, class C: remove screw completely

Push the cover back; FS III: lift the cover carefully

Do not stand arc chutes up, when placing them on a table, or any other surface outside of the circuit breaker. The arc chutes should be placed on their side to prevent breakage of the insulation plates.

Sign off on the arc chute removal