Flowserve DFC17 - Manual (Page 26)

26 DataFlo Digital Electronic Controller DFC17 Installation, Operation and Maintenance Instructions WCAIM2026
Flow Control Division
Worcester Actuation Systems
6.3 Troubleshooting Guidelines
Use the following troubleshooting guidelines to isolate
problems/bad components.
Prior to beginning any procedure, read all of Check, Action, and
Notes and Cautions sections.
CHECK ACTION NOTES AND CAUTIONS
6.3.1 Check for proper AC/DC power to actuator and Correct as necessary.
circuit board. See Figures 2, 3 or 4.
6.3.2 With power off, check for broken wires and/or Repair broken wires and
loose connections. tighten loose connections.
6.3.3 With power off, check to see if fuse F1 is blown. Remove F1 from socket Before restoring power, try to
(For DC boards, see paragraph 6.1.2 also.) pins and check for determine what caused F1 to blow
continuity through fuse with and correct problem. See part 3.2
an ohm meter. If F1 is bad, Note and Paragraph A of Part 1.1, and
replace it with a new fuse. also paragraph 6.1.2.
6.3.4 Check operation of basic See Part 6.1. This check will isolate the problem to
Setpoint actuator per Part 6.1. either the actuator or the circuit board.
6.3.5 Check for proper range of setpoint and Use ammeter, voltmeter or See models listed at beginning of IOM
process input signals. ohmmeter to verify input for ranges. 4–20 mA is most common.
signal range.
6.3.6 Check calibration of feedback potentiometer. With shaft in full CW position, When trying to move the valve
adjust pot for a reading between manually with the clutch disengaged,
.200 and .400 volts. Recalibrate be certain that the wrench fits
per part 4.2 if necessary. properly on the flats of the actuator
shaft. Improper fit can cause shaft
damage with consequent damage to
cover bearing surface. Stay within the
preset quadrant of operation. See
Paragraph C of Part 1.1.
6.3.7 Check to see that varying the process If LEDs do not turn on and off, The turning on and off of the LEDs
signal above and below the Setpoint value replace board. is indicative that the input side of the
causes the light emitting diodes (LEDs) to circuit board is OK.
turn on and off individually.
6.3.8 Check the operation of the Controller with a If intermittent or jittery operation Increasing the deadband may help to
portable, battery-operated Process signal stops, it is indicative of a noisy alleviate the problem.
source if possible or some other appropriate online signal input. To avoid
process signal simulator. damaging the actuator, it is
necessary to “clean up” the signal.
Also, follow the shielding guidelines
of Paragraphs 1.2 and 1.2.3.
6.3.9 Check the motor run capacitor for a short, Replace as necessary. Disconnect all leads from capacitor
excessively high leakage and low terminals (power off) prior to testing.
capacitance. Use a capacitance meter to Do not exceed rated voltage of
check. (AC boards only) capacitor. Make certain that
capacitor is discharged before
reconnecting.
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