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Electrical Specification and Certification

Power supply Torque Limit switch mechanism

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WT actuators are suitable for operation with the following 3 phase, 3 wire nominal power supplies: The unique combined torque and travel limit switch mechanism allows the actuator to be fitted to any valve type. Actuator wiring diagrams do not vary with the valve.Simple mechanical selectors are set for torque or limit tripping to suit both seating (torque) or non seating (position limit) type valves. Selectors for both opening and closing torque switch protection are included to make site adjustment simple.The valve turns range is set by lead screw adjustment that mimics actuator output turns. In addition two open and two close auxiliary switched are provided as standard for remote end of travel indication or interlocking. A mechanical 3 position pointer and dial provides local valve close, intermediate and open position indication. Refer to publication E320E for full description. 50Hz 220, 240, 380, 400, 460, 500, 525 and 550 Volts. 60Hz 208, 220, 230, 240, 380, 440, 460, 480, 575 and 600 Volts.The required operating voltage must be specified at the time of Order.Actuator performance is guaranteed with a voltage tolerance +/-10% and a frequency tolerance +/-5 HZ. Actuators are capable of starting and running up to speed with a maximum 15% volt drop. For power supply tolerance or volt drop in excess of those stated above, please apply.

Uninterruptible power supplies UPS

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WT actuators are suitable for use with UPS Power supplies provided the tolerances specified above are not exceeded. UPS output should adhere to recognised supply standards such as EN50160.

Wiring and terminations

Jig built harnesses of individually stranded conductors, tropical grade PVC insulated, connect internal components to the applicable terminal compartment. All wires are identified with printed numbers.Refer to SyncroSET and SyncroPAK specifications for details of user termination.All actuators include the Installation and Maintenance Manual - publication E370E, wiring diagram and commisioning bag.

Motor

The integral 3 phase squirrel cage induction motor is specially designed for valve actuation. Class F insulated with winding thermostat, the low inertia, high starting and stalling torque motor provides substantial reserves of power to assure torque switch operation at maximum setting with a voltage reduction as much as 10% below nominal.Due to the low inertia design and lost motion or “hammerblow” drive, starting is instantaneous within 3 cycles of the mains frequency.Motors are 15 minutes rated with a cyclic duration factor of 25% at 33% of actuator output rated torque giving a temperature rise not exceeding that permitted for class B insulation at standard nominal voltage.Actuators are rated S2/S3 to IEC60034-1, 60 starts per hour at a rate not exceeding 600 starts per hour. Where long running times or regulation in excess of that stated above are required, alternative motor insulation class and rating are available. Please apply.Refer to publication E330E for motor electrical data.

Option Add-on-Pak (AOP)

The Add on Pak is an optional extra and provides a range of indication options in addition to the standard switch mechanism: t Continuous local valve position indication t 2 or 6 additional, independant, auxiliary switches for valve indication or interlocking t Remote analogue valve position indication – voltage or current.Gear driven from the switch mechanism, the Add on Pak can be factory fitted or retrofitted in the field if plant indication requirements change. The AOP can be fitted to any A
WT SyncroPAK or SyncroSET actuator. Refer to publication E320E for full description.

Motor thermostat Option Folomatic

The motor thermostat enables the control circuit to be tripped and motor disconnected if the maximum permitted winding temperature is reached. This protection is independent of ambient temperature variation and motor current and provides optimum usage of motor thermal capacity. The thermostat will auto reset on motor cooling.For SyncroSET actuators it is vital that the motor thermostat is connected in series with the motor reversing contactor coils. Refer to publication E320E. This control option enables a Syncropak actuator to position a valve in proportion to analogue signal. It is suited to control applications with relatively slow rates of change and where high accuracy, high modulation are not a requirement such as level controls in water and sewage systems. See publication E320E.

Established Leaders E s t a b i h e d in Valve Actuation Technology

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