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

45Instruction Booklet IB131006ENEffective March 2019Instructions for installation,operation, and maintenance of typeVCP-W vacuum circuit breakersEATON www.eaton.comWhen the CS/C contact is made, the SR closes the circuit breaker.If the CS/C contact is maintained after the circuit breaker closes, theY relay is picked up. The Y/a contact seals in Y until CS/C is opened.The Y/b contact opens the SR circuit, so that even though the circuitbreaker would subsequently open, it could not be reclosed beforeCS/C was released and remade. This is the anti-pump function.5.4.1 TimingThe opening and closing times for the circuit breakers vary depend-ing upon the control voltage and the power rating. Typical values forVCP-W breaker elements are shown in Table 22.Table 22. Circuit breaker timing (made while the circuit breakeris levered to the CONNECTED position).Event Milliseconds (maximum)Closing time(From Initiation of close signal to contact make) 45-60Opening time(Initiation of trip signal to contact break) 30-45Reclosing time(Initiation of trip signal to contact make) 140-1655.4.2 Secondary disconnectsThe circuit breaker control wiring is arranged to connect a standard25 point male plug with a corresponding switchgear compartmentmounted female plug. The circuit breaker plug is fixed mountedon the left side under the bottom pan of the mechanism (Figure15). The female plug is mounted in the compartment on a movablecarriage (Figure 12 and 13).To engage secondary contacts:• For BPI: secondary contacts engage automatically in TESTposition• For non-BPI: raise the handle and pull the carriage all the waytowards the front (Figure 16).• For automatic/manual hybrid: raise the handle, spring pres-sure will force the carriage all the way towards the front. Checkcontacts fully engaged.To disengage secondary contacts:• For BPI: rack the breaker to the DISCONNECT position.• For non-BPI: push the carriage to the rear, contacts willdisengage.• For automatic/manual hybrid: push the carriage to the rearagainst spring pressure, contacts will disengage. Allow carriagehandle to catch in latch cutout of mechanism.5.4.3 Shunt trip deviceThe shunt trip device is an electro-mechanical device that operatesto open the circuit breaker. When the coil is energized by someextenal source, it will trip the breaker open. The shunt trip deviceis available with rated voltages of 24 Vdc, 48 Vdc, 125 Vdc, 250 Vdc,120 Vac, and 240 Vac. A cap trip device must be used with the 120Vac and 240 Vac options. If needed, continuous trip coil monitoringis available. Also there is an option to have a second shunt tripwhich can be rated at a different voltage other than the voltagespecified for the primary shunt trip.5.4.4 Under-voltage trip deviceThe under-voltage trip device for VCP-W circuit breakers is an electro-mechanical device that operates to open the circuit breaker at 30%or less of the voltage rating of the trip coil. The device does notopen the circuit breaker at values above 60% of the voltage ratingof its trip coil. It may operate, however, to open the circuit breakerwhen the voltage across the trip coil is greater than 30%, but lessthan 60% of the voltage rating of its trip coil. The circuit breaker canbe closed as long as the voltage to the trip coil is maintained at 85%or above the rated level. The under-voltage trip device is availableonly as an instantaneous type with rated voltages of48 Vdc, 125 Vdc, 250 Vdc, 120 Vac, and 240 Vac.For a basic understanding of the operation of the under-voltage tripdevice refer to the specific items identified in Figure 24 and thefollowing operation description.1. With the circuit breaker closed and sufficient voltage on theunder-voltage trip device coil, the moving clapper (1) is heldto the stationary yoke (2) by the magnetic force produced bythe coil (3) against the extension springs (4) pulling the movingclapper apart from the yoke.2. The moving clapper is connected to the mechanism trip “D”shaft lever (5) by a slotted link (6).3. When the voltage to the under-voltage trip coil goes down asdescribed earlier, the extension springs force overcomes thereduced magnetic force and pulls the moving clapper up. Theslotted link in turn upsets the trip “D” shaft and the circuitbreaker trips open.4. As the circuit breaker opens, the reset lever (8) connected to thepole shaft lever (7) operates to reset the moving clapper. As longas the circuit breaker remains open, the reset lever holds downthe moving clapper to the yoke.5. When the circuit breaker closes, the reset lever moves awayfrom the moving clapper. If the under-voltage trip device coil hasat least 85% of the rated voltage applied, the moving clapper isheld to the yoke by the magnetic force, even though the resetlever has moved up.