Dwyer ACT - Manual (Page 8)

Note: To speed up installation of the control wires to the ACT-MDXX modulating
actuator, it is recommended to remove the control module from the actuator. The
control module can be removed by removing the two mounting screws on the left
and right of the control module. Install the control wires to the correct terminal points
and then reinstall the control module.
Electric Actuator Maintenance
Once the actuator has been properly installed, it requires no maintenance. The gear
train has been lubricated and in most cases will never be opened.
Duty Cycle Definition
“Duty Cycle” means the starting frequency.
Fomula: Running Time (Running Time Rest Time) x 100% = duty cycle
Rest Time = Running Time x (1 - duty cycle) duty cycle
For example: The running time is 15 seconds
30% duty cycle 15 x [(1 - 30%) / 30%] = 35 The rest time will be 35 seconds
75% duty cycle 15 x [(1 - 75%) / 75%] = 5 The rest time will be 5 seconds
If the duty cycle is higher, the rest time will be shortened. It means the starting
frequency will be higher.
Thermal Overload
All actuators are equipped with thermal overload protection to guard the motor
against damage due to overheating.
Mechanical Overload
All actuators are designed to withstand stall conditions. It is not recommended to
subject the unit to repeated stall conditions.
Explosion-Proof Electric Actuators
1. DO NOT under any circumstances remove the cover of the
actuator while in a hazardous location. Removal of the cover
while in a hazardous location could cause ignition of hazardous atmospheres.
2. DO NOT under any circumstances use an explosion-proof electric actuator in a
hazardous location that does not meet the specifications for which the actuator was
designed.
3. Always verify that all electrical circuits are de-energized before opening the
actuator.
4. Always mount and cycle test the actuator on the valve in a non-hazardous
location.
5. When removing the cover, care must be taken not to scratch, scar of deform the
flame path of the cover and base of the actuator, since this will negate the NEMA
rating of the enclosure.
6. When replacing the cover, take care that the gasket is in place to assure proper
clearance after the cover is secured.
7. All electrical connections must be in accordance with the specifications for which
the unit is being used.
8. Should the unit ever require maintenance, remove from the hazardous location
before attempting to work on the unit.
If the actuator is in a critical application, it is advisable to have a standby unit in stock.
WARNING
Wiring Diagrams for
TD01-TD06: 24 VDC
Wiring Diagrams for
TD01-TD09: 120 VAC, TD01-TD09: 220 VAC, TD01-TD09: 24 VAC
Wiring Diagrams for
MD01-MD09: 120 VAC, MD01-MD09: 220 VAC, MD01-MD09: 24 VAC
Electric Actuators Wiring Diagram: ACT-TD & ACT-MD
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