Eaton Cutler-Hammer W-VAC Instructions For Installation, Operation And Maintenance

I.B. 3A74791H04Page 24Effective 7/974. As the circuit breaker opens, the reset lever (8) con-nected to the pole shaft lever (7) operates to resetthe moving clapper. As long as the circuit breakerremains open, the reset lever holds down the movingclapper to the yoke.5. When the circuit breaker closes, the reset levermoves away from the moving clapper. If the Under-voltage Trip Device coil has at least 85% of the ratedvoltage applied, the moving clapper is held to theyoke by the magnetic force, even though the resetlever has moved up.5-5 INTERLOCKS AND INTERFACINGRefer to Paragraph 4-9 of this manual for detailed infor-mation concerning circuit breaker interlocks and theirinterfacing with a switchgear structure compartment. Inaddition, refer to the instruction manual supplied withthe switchgear assembly.5-6 LEVERING MECHANISMThe purpose of the levering mechanism is to move thecircuit breaker into and out of the CONNECTED positionwithin the assembly structure. The levering mechanismused to move the 36kV W-VAC circuit breaker is a mini-mum effort recirculating ball drive design, and is part ofthe assembly structure cradle. For additional informationconcerning the levering mechanism, refer to the instruc-tion manual supplied with the switchgear assembly.Paragraph 4-8.1 of this manual provides details con-cerning the use of the levering mechanism to move thecircuit breaker into and out of the CONNECTED positionwithin the assembly structure.5-7 OPERATIONS COUNTERAll circuit breakers are equipped with a mechanicaloperations counter. As the circuit breaker opens, thelinkage connected to the pole shaft lever advances thecounter reading by one (Figure 3-7).5-8 GROUND CONTACTThe ground contact is an assembly of spring loaded fin-gers providing a disconnectable means for groundingthe circuit breaker chassis, after it has been insertedinto a switchgear structure. The ground contact is locat-ed on the lower left portion of the truck chassis. Anextension of the switchgear ground bus is secured tothe cell floor in such a position to engage the groundcontact automatically, when the circuit breaker is movedinto the DISCONNECT/TEST position. It remainsengaged in all other circuit breaker positions within thecell.5-9 MOC AND TOC SWITCH OPERATIONSA MOC operator integral to the circuit breaker engagesan operating lever of the Mechanism Operated CellSwitch (MOC) located in the switchgear cell. This MOCoperator permits the contacts of the MOC Switch to becorrelated with the circuit breaker’s contact position.The cell mounted Truck Operated Cell Switch (TOC) isoperated by movement of the circuit breaker truck intoor out of the CONNECTED position.