Attach the spool coupler assembly (294-A & B) to the spool using washer (404-D) and E-ring (404) on mRoy B
units or setscrew (256) on mRoy A units. The A unit setscrews must engage the spool groove. Be careful not to
change the position of the control spool. Tighten motor and transfer pulley setscrews.
Loosen indicator pulley setscrews (410-D). Move the potentiometer with the pulley and belt until the resistance
across terminals 4 and 5 is 10 ohms or less at the zero position for 250-ohm pot; 40 ohms or less for 1000-ohm
pot. Tighten indicator pulley setscrews.
Carefully replace the limit switch plate without disturbing the zero spool position (hold the spool). Adjust the plate
position until the zero limit switch is just actuated by the spool coupler and tighten the mounting screw securely.
Run the actuator toward 100 percent until it contacts the limit switch and shuts off.
Resistance across terminals 4
and 5 should be 235 ohms or more for 250-ohm pot; 940 ohms or more for 1000-ohm pot. Run the actuator back
to zero percent. Re-check resistance as per step 10, and adjust if necessary via the indicator pulley.
Apply 115v. AC to terminals 7 and 9 to drive the unit toward the 100 percent limit switch. Verify that the
potentiometer is not driven against its internal stop and that the limit switch operates. The unit will function
properly provided the zero position of the control spool was maintained during assembly.
At the 100 percent position, set the indicator (298-A & 253-B) to 100 percent by loosening the locking screw (405-
E) and rotating the pointer in the required direction. Retighten screw.
Attach control wiring and feed through the conduit. Beyond the conduit, isolate alternating current wires from
wires carrying electric signals.
Seat the actuator cover (281-A) in the gasket groove with the large sealing washers (408-A) under the cover
screws (rubber side against housing). Tighten the cover screws securely.