Eaton 380 VCP-W 16 Instructions For Installation, Operation And Maintenance

Also see for 380 VCP-W 21: Instructions for installation, operation and maintenance

Contents

Page 38 I.B. 3A74792H08Effective 0 9 / 20 1 4Figure 6-2 Rear Measurement for Contact ErosionBeing Made (Circuit Breaker Closed)6-7 INSULATIONType VCP-W and VCP-WR 38kV Vacuum CircuitBreakers primarily utilize cycloaliphatic epoxy insulationexcept, for example, the black insulating shrouds.Insulation maintenance primarily consists of keeping allinsulating surfaces clean. This can be done by wipingoff all insulating surfaces with a dry lint free cloth or drypaper towel. In case there is any tightly adhering dirtthat will not come off by wiping, it can be removed with amild solvent or distilled water. Be sure that the surfacesare dry before placing the circuit breaker in service. If asolvent is required to cut dirt, use Stoddard’s SolventEaton 5581 2CA or commercial equivalent. Secondarycontrol wiring requires inspection for tightness of allconnections and damage to insulation.6-8 INSULATION INTEGRITY CHECKPrimary Circuit:The integrity of primary insulation may be checked by the60Hz AC high potential test. The test voltage dependsupon the maximum rated voltage of the circuit breaker.For circuit breakers rated 38kV the test voltage is 60kVrms. Conduct the test as follows:Close the circuit breaker. Connect the high potentialFigure 6-3 Graphical Representation of ContactErosion Measurement (Circuit Breaker Closed)lead of the test machine to one of the poles of thecircuit breaker. Connect the remaining poles andcircuit breaker frame to ground. Start the machinewith output potential at zero and increase to the testvoltage. Maintain the test voltage for one minute.Repeat for the remaining poles. Successful withstandindicates satisfactory insulation strength of theprimary circuit.If a DC high potential machine is used, make certainthat the peak voltage does not exceed the peak of thecorresponding AC rms test voltage.Secondary Circuit:Connect all points of the secondary terminal blockwith shooting wire. Connect this wire to the highpotential lead of the test machine. Ground the circuitbreaker frame. Starting with zero, increase thevoltage to 1125 volts rms. Maintain the voltage forone minute. Successful withstand indicatessatisfactory insulation strength of the secondarycontrol circuit. Remove the shooting wire.6-9 PRIMARY CIRCUIT RESISTANCE CHECKSince the main contacts are inside the vacuumchamber, they remain clean and require nomaintenance at any time. Unlike many typical circuitbreaker designs, VCP-W and VCP-WR circuitbreakers do not have