Eaton VCP-W Series Instructions For Installation/operation/maintenance/servicing

Also see for 120VCP-W25: Installation, operation and maintenance Instructions for installation, operation and maintenance

Contents

53Instruction Booklet IB131006ENEffective March 2019Instructions for installation,operation, and maintenance of typeVCP-W vacuum circuit breakersEATON www.eaton.com6.6 InsulationType VCP-W circuit breaker insulation maintenance primarily consistsof keeping all insulating surfaces clean. This can be done by wipingoff all insulating surfaces with a dry lint free cloth or dry paper towel.In case there is any tightly adhering dirt that will not come off bywiping, it can be removed with mild solvent or distilled water. Besure that the surfaces are dry before placing the circuit breaker inservice. If a solvent is required to cut dirt, use Stoddard’s SolventEaton 55812CA or commercial equivalent. Secondary control wiringalso requires inspection for insulation damage.6.7 Insulation integrity checkPrimary circuit:The integrity of primary insulation may be checked by the 60 Hz AChigh potential test. The test voltage depends upon the maximumrated voltage of the breaker. For the breaker elements rated 4.76 kV,8.25 kV, 15 kV, and 27 kV, the test voltages are 15 kV, 27 kV, 27 kV,and 45 kV RMS respectively. Conduct the test as follows.Close the breaker. Connect the high potential lead of the testmachine to one of the poles of the breaker. Connect the remainingpoles and breaker frame to ground. Start the machine with outputpotential at zero and increase to the test voltage. Maintain the testvolt-age for one minute. Repeat for the remaining poles. Successfulwithstand indicates satisfactory insulation strength of the primarycircuit.If a DC high potential machine is used, make certain that the peakvoltage does not exceed the peak of the corresponding AC RMS testvoltage.Secondary circuit:Isolate the motor by pulling apart the two insulated quick discon-necting terminals in the two motor leads provided for this purpose,or remove the two motor wires from the ring tongue terminals(Figure 5). Connect all points of the secondary disconnect pins withshooting wire. Connect this wire to the high potential lead of thetest machine. Ground the circuit breaker frame. Starting with zero,increase the voltage to 1125 Vac RMS, 60 Hz. Maintain the voltagefor one minute. Successful withstand indicates satisfactory insula-tion strength of the secondary control circuit. Remove the shootingwire and reconnect motor leads.6.8 Primary circuit resistance checkSince the main contacts are inside the vacuum chamber, theyremain clean and require no maintenance at any time. Unlike manytypical circuit breaker designs, VCP-W breakers do not have slidingcontacts at the moving stem either. Instead they use a highly reli-able and unique flexible clamp design that eliminates the need forlubrication and inspection for wear.If desired, the DC resistance of the primary circuit may be measuredas follows:• Close the circuit breaker, pass at least 100 amps DC currentthrough the circuit breaker. With a low resistance instrument,measure resistance across the studs on the circuit breaker side ofthe disconnects for each pole.The resistance should not exceed the values shown in Table 25.Table 25. Typical resistance measurements.Rated continuous current(amperes) Resistance(microohms)1200200030006040206.9 Mechanism checkMake a careful visual inspection of the mechanism for any looseparts such as bolts, nuts, pins, and rings. Check for excessive wearor damage to the circuit breaker components. Operate the circuitbreaker several times manually and electrically. Check the closingand opening times to verify that they are in accordance with thelimits in Table 22.6.9.1 CloSure™ testIntroductionThe CloSure test is a simple yet extremely effective means to deter-mine and monitor the ability of the mechanism to close the breakercontacts fully. It provides a quantitative measure of the extraenergy available in terms of over travel in inches to close the breakercontacts to their full extent. It maybe used periodically to monitorthe health of the mechanism.At times, circuit breakers are called upon to operate mechanismoperated cell (MOC) switches that place extra load upon the closingmechanism of the circuit breaker. If this load is excessive, it canprevent the circuit breaker from closing fully. In such a case, it isimportant to determine that the circuit breaker will close fully. TheCloSure test provides this assurance.General informationThe CloSure test can be per-formed on the VCP-W, VCP-WR, VCPW-ND, DHP-VR, W-VACR, and W-VAC lines of vacuum circuit breakers.Refer to Table 26 a for list of circuit breakers. If the CloSure travelobtained is as specified, the mechanism performance is satisfactory.If the CloSure travel does not conform as shown in Figure 36, con-tact Eaton for further information (see Step 13).m WARNINGDO NOT ATTEMPT TO INSTALL OR PERFORM MAINTENANCE OR TESTS ONTHE EQUIPMENT WHILE IT IS ENERGIZED. NEVER PUT YOUR HANDS NEARTHE MECHANISM WHEN THE CIRCUIT BREAKER IS IN THE CHARGED ORCLOSED POSITION. DEATH OR SEVERE PERSONAL INJURY CAN RESULTFROM CONTACT WITH ENERGIZED EQUIPMENT. ALWAYS VERIFY THAT NOVOLTAGE IS PRESENT BEFORE PROCEEDING WITH THE TASK AND ALWAYSFOLLOW GENERALLY ACCEPTED SAFETY PROCEDURES.6.10 Megger and power factor testingBoth the megger and power factor type testing of high voltageinsulation are not recognized by IEEE as a design, production, orconformance test for determining product acceptance during initialcommissioning. If an end user wishes to use these tests for trend-ing purposes, then they should record the initial readings duringcommissioning along with temperature and humidity during thetesting. The trend of the test results should be tracked over the lifeof the product and any abnormalities should be investigated.Safety precautionsRead and understand these instructions before attempting any main-tenance, repair, or testing on the breaker. The user is cautioned toobserve all recommendations, warnings, and cautions relating to thesafety of personnel and equipment.The recommendations and information contained herein are basedon Eaton experience and judgment, but should not be considered tobe all-inclusive or covering every application or circumstance whichmay arise. If further information is required, you should consultEaton.