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Pumps
Pumps
Pumps Do
Do
Do Not
Not
Not Reverse
Reverse
Reverse Direction
Direction
Direction
For proportioning pumps to reverse direction,
the proximity switches (211) must sense the
switching plate (319) to reverse the directional
valve (207).
DANGER
DANGER
DANGER
SEVERE
SEVERE
SEVERE ELECTRIC
ELECTRIC
ELECTRIC SHOCK
SHOCK
SHOCK
This equipment can be powered by more than
240 V. Contact with this voltage will cause
death or serious injury. When accessing the
electrical enclosure while power is present:
• Do not make contact with components or
wires unless instructed to do so.
• Wear appropriate personal protective
equipment.
See
Electrical Schematics, page 105
.
The switching plate moves from side to
side during operation. Keep hands away
from the switching plate, while checking the
functionality of the directional valve, to prevent
pinching hands.
1. Check the functionality of each proximity
switch (211).
a. Remove the front cover.
b. With the motor powered off, confirm that
the indicating lights on the body of each
proximity switch (211) turns on when
a metallic item, such as the shaft of a
screwdriver, is placed on the face of each
switch.
c. If the indicating lights turn on, the
proximity switches, its wiring, and the
HCM are likely operating correctly;
proceed to step 2. If the indicating lights
do not turn on, proceed to step 6.
2. Confirm the proximity switches (211), switch
bracket (209), and switching plate (319) are
firmly mounted and not damaged.
3. Check distance between the proximity
switches (211) and the switching plate (319).
a. Park the pump.
b. Confirm that the proximity switch (211)
nearest the A-side of the pump is
backed out 0.5 to 1.5 turns from being
in contact with the switching plate (319).
c. Disconnect the cable from the proximity
switch (211) nearest the B-side of the
pump. Operate the pump until the
switching plate (319) is located above
the B-side proximity switch, then turn
off the motor/pump.
d. Confirm that the proximity switch (211)
nearest the B-side of the pump is backed
out 0.5 to 1.5 turns from being in contact
with the switching plate (319).
e. Reconnect the cable to the B-side
proximity switch (219).
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