Flowserve DFC17 - Manual (Page 27)

WCAIM2026 DataFlo Digital Electronic Controller DFC17 Installation, Operation and Maintenance Instructions 27
Flow Control Division
Worcester Actuation Systems
continued from previous page
CHECK ACTION NOTES AND CAUTIONS
6.3.10 Check temperature of motor(s). Allow the motor(s) to cool so that Duty cycle is specified at an ambient
One AC motor has a thermal cutout the thermal switch can reset. temperature of 70°F, 60 Hz.
switch built in that opens at about Normally the thermal switch
210°F (winding temperature). If the will not open unless the motor’s
thermal cutout has opened, both motors rated duty cycle is exceeded
are deenergized until the thermal switch and/or the ambient temperature
resets (20-2375 sizes). is very high. Correct the problem.
6.3.11 Check the operating torque of the valve. If If operating torque of valve exceeds If the actuator is removed from a
necessary, remove the actuator from the valve. the specified torque for the seats three-piece valve that requires the body
Measure valve torque with an accurate torque used and the DP across the bolts to also be removed, the valve
wrench. Check torque under actual operating valve, determine cause and body bolts must be retorqued to
conditions if possible. correct. If torque falls within specifications before checking valve
normal range, it is possible that torque. See Valve IOM.
the actuator is undersized.
6.3.12 Check ambient temperature. Actuator duty cycles are Higher ambient derates duty cycle.
specified at an ambient
temperature of 70°F.
6.3.13 Check to see that mechanical brake is Replace defective mechanical All 2" CPT valves with Controller
operating correctly. brake. If one was never installed, boards in actuator must have
order a kit and install it in actuator. mechanical brake installed
to prevent oscillation.
6.3.14 Check to see if actuator can move a high If motor(s) cannot start, go to next
torque valve from a stop under load when larger size actuator.
moving in the same direction as last command
(mechanical brake does not allow motor(s) to
unwind).
6.3.15 Check to see which direction of travel Replace circuit board.
causes problem. If actuator is coming off
open limit switch (traveling CW) when it slows
down or stops, then either Q1 or U1 is bad.
If actuator is coming off closed limit switch
(traveling CCW), then either Q2 or U2 is bad.
(AC boards only)