47-602 F10 and F50 Flow Switches
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4.1.2 Test Control’s Performance
If switch mechanism is operating satisfactorily, a test of the
complete control’s performance is the next likely step.
1. Reconnect power supply, and carefully actuate switch
mechanism manually, using a non-conductive tool, to
determine whether controlled equipment will operate.
Caution:
With electrical power on, care should be taken to avoid
contact with switch leads and connections at terminal
block
.
2. If controlled equipment responds to manual actuation test,
trouble may be located in the flow sensing portion of the
control.
NOTE: Check first to be certain liquid is flowing through pipeline.
A valve may be closed, or pipeline may be plugged.
3. If magnet fails to pull in on increasing flow:
a. Disk or vane may not be sized properly for required
actuation flow rate.
b. Check for hang-up or deposits in disk seat or at
vane pivot.
c. Check for malfunctioning by manually moving magnet
carriage.
4. If magnet fails to pull out on decreasing flow:
a. Disk or vane may not be sized properly for required
actuation flow rate.
b. Check for hang-up or deposits in disk seat or at vane
pivot.
c. Check for malfunctioning by manually moving magnet
carriage.
If all components in the unit are in operating condition,
the trouble must be located external to the unit. Repeat
inspection of external conditions previously described.
