Potter Releasing Systems - Manual (Page 71)

71
MFG. #5400979 - REV S
5/09
PRINTED IN USA PAGE 3 OF 4
OSYSU-1,-2
OUTSIDE SCREW AND YOKE
VALVE SUPERVISORY SWITCH
FIG. 2 LARGE VALVE INSTALLATION - 3" THRU 12" SIZES
LARGE VALVE INSTALLATION
1. With the valve in the FULL OPEN position, locate the OSYSU across
the valve yoke as far as possible from the valve gland, so that the trip
rod lays against the non-threaded portion of the valve stem.
2. Mount the OSYSU loosely with the carriage bolts and clamp bar
supplied.
3. Loosen the locking screw that holds the trip rod in place and adjust
the rod length (see Fig. 4). When adjusted properly, the rod should
extend past the valve screw, but not so far that it contacts the clamp
bar. Tighten the locking screw to hold the trip rod in place.
NOTE: If trip rod length is excessive, loosen the locking screw
and remove the trip rod from the trip lever. Using pliers, break off
the one (1) inch long notched section (see Fig. 5). Reinstall trip rod
and repeat Step 3 procedure.
4. Mark the valve stem at the center of the trip rod.
5. Remove the OSYSU. File a 1/8" deep groove centered on the mark
of the valve stem utilizing a 3/8" diameter straight file. Round and
smooth the edges of the groove to prevent damage to the valve
packing and to allow the trip rod to move easily in and out of the
groove as the valve is operated.
6. Mount the OSYSU loosely with the trip rod centered in groove.
7. Final adjustment is made by loosening 2 screws (see Fig. 2) and
sliding the OSYSU on the bracket. Adjustment is correct when
switches are not activated with the trip rod seated in the valve stem
groove and that the switches activate within one turn when the valve
is operated from the FULL OPEN towards the CLOSED position.
8. Tighten the adjustment screws and mounting hardware. Check to
insure that the rod moves out of the groove easily and that the switches
activate within one turn when the valve is operated from the FULL
OPEN towards the CLOSED position.
NOTE: CLOSE THE VALVE FULLY TO DETERMINE THAT THE
STEM THREADS DO NOT ACTIVATE THE SWITCH. THE SWITCH
BEING ACTIVATED BY THE STEM THREADS COULD RESULT
IN A FALSE VALVE OPEN INDICATION.
3” THRU 12” (76mm THRU 300mm) VALVES
USE CARRIAGE BOLTS. BOLTS MOUNT
ON INSIDE OF YOKE, IF THERE IS
SUFFICIENT CLEARANCE.
SLOTTED
MOUNTING HOLES.
MAY BE USED FOR
FINE ADJUSTMENT
OF SWITCH ON
BRACKET.
DWG# 979-4
BRACKET
CLAMP BAR
CARRIAGE BOLTS
(2 REQUIRED)
ROLLER
GROOVE
YOKE
VALVE STEM
TRIP ROD
GLAND