MODEL Q-5SS
INSTALLATION INSTRUCTION SHEET
SPDT 15 AMP MICROSWITCH 125/240 VAC (2 REQ'D FOR QD-5SS)
DRY CIRCUIT MICROSWITCH SPDT 0.1A 125 VAC (OPTIONAL)
3 WIRES WITH CRIMPED TERMINALS (6 TERMS. ONLY QD-5SS)
2 SCREWS, NUTS & LOCKWASHERS
HARWIL CORPORATION
541 KINETIC DRIVE, OXNARD, CA 93030
TEL: (805) 988-6800 FAX: (805) 988-6804
EMAIL: HARWIL@HARWIL.COM
TERMINAL STRIP
(NOT SUPPLIED WITH QD-5SS)
COVER CASTING,
SEAL, SCREW ASSEMBLY
CABLE STRAIN RELIEF
DRAG DISK 1
DRAG DISK 2
DRAG DISK 3
DRAG DISK 4
DRAG DISK 5
DRAG DISK 6
GASKET
BODY CASTING
BRACKET
2 SPACERS
2 SCREWS & LOCKWASHERS
LEADSCREW
LEADSCREW NUT
SPRING
LID CASTING
7 SCREWS & LOCKWASHERS
CLAMP WASHER
3 SCREWS & LOCKWASHERS
FEED THRU SHAFT ASSEMBLY
MODEL Q5SS/3
MODEL Q5SS/5
MODEL Q5SS/7
This parts list applies to all models of Q-5SS and QD-5SS uid ow switches: Q-5SS/5, Q-5SS/7,
QD-5SS/3, and QD-5SS/7. All letters and numbers added to model number after the above numbers
apply to optional drag strips and electrical strain relief connectors.
PARTS LIST
FLUID FLOW SWITCH
2D
5D
TURBULENT
FLOW REDUCTION
MODELS
Q-5SS
QD-5SS
MOUNT IN
ANY POSITION
ULTRA RELIABLE SINCE 1956 P. 1
HARWIL CORPORATION
MODEL Q-5SS
INSTALLATION INSTRUCTION SHEET
541 KINETIC DRIVE, OXNARD, CA 93030
TEL: (805) 988-6800 FAX: (805) 988-6804
EMAIL: HARWIL@HARWIL.COM
INSTALLATION AND OPERATING INSTRUCTIONS
The gasket seal located between the main body casting and the lid casting is a cork-rubber composition, which is subject to a slight creep for a short period after application of the initial clamping load.
All gaskets are properly clamped before shipment, however during shipping and storage, the gasket
may compress, allowing the body-lid clamp bolts to become slightly loose. Tighten these bolts before
assembling the ow switch in-system. No further creep of gasket will occur after second tightening. The
Q-5SS uid ow switch is supplied with a male 1” NPT which is threaded into an appropriate pipe tee,
large pipe with reducer bushing, or directly into a hole threaded 1” NPT in the wall of the pipe. Turn
until tight and arrow on body casting is pointed in direction of ow.
ELECTRICAL WIRING
FIGURE 1: Wiring schematic for power applied to load when ow is GREATER than the set point (power to load interrupted when ow is LESS than set point).
INCREASING FLOW MOVES
ACTUATOR IN DIRECTION SHOWN
NC (ORANGE)
NO (WHITE)
COM (BLACK)
MICROSWITCH
(HOT)
TERMINAL STRIP
LOAD
LINE
FIGURE 2: Wiring schematic for power applied to load when ow is LESS than the set point (power to
load interrupted when ow is GREATER than set point).
DECREASING FLOW MOVES
ACTUATOR IN DIRECTION SHOWN
NC (ORANGE)
NO (WHITE)
LOAD
MICROSWITCH
COM (BLACK)
ULTRA RELIABLE SINCE 1956P. 2
TERMINAL STRIP
(HOT)
LINE
MODEL Q-5SS
INSTALLATION INSTRUCTION SHEET
FLOW SWITCH OPERATIONAL ADJUSTMENT
REMOVE COVER
LEADSCREW
MICROSWITCH
HARWIL CORPORATION
541 KINETIC DRIVE, OXNARD, CA 93030
TEL: (805) 988-6800 FAX: (805) 988-6804
ADJUST LEADSCREW
BEST ADJUSTMENT POINT
(CENTERED)
SPRING POSITION
WHEN DELIVERED
EMAIL: HARWIL@HARWIL.COM
SWITCH POINT ADJUSTMENT
1. Remove cover.
2. Adjust uid ow in system to desired rate WITHOUT regard to Q-5SS switch point setting.
3. The switch point adjusting mechanism consists of an adjusting screw, a “U” shaped lead screw nut,
and a helical spring.
CLOCKWISE rotation of the adjusting screw changes the microswitch actuation point toward HIGHER
ow rates.
NOTES: All Q-5SS units are factory set at the lower end of the ow range, e.g. the adjusting screw is
set at the low ow counter-clockwise position.
The lead screw nut locks the adjusting screw in position, maintaining the ow switch set point under all
environmental conditions.
4. Turn the adjusting screw in a clockwise direction until the microswitch is actuated, while maintaining
the desired uid ow rate in the system. Turn the adjusting screw TWO (2) additional turns in the
clockwise direction and then slowly back off in a counter-clockwise direction, until the microswitch
is again actuated. The Q-5SS ow switch is now set for maximum sensitivity for detecting small ow
changes.
5. When set for maximum sensitivity (100% point) as described above, ow turbulence may cause
rapid on/off switching (dithering) of the microswitch contacts, resulting in reduced switch contact life
ULTRA RELIABLE SINCE 1956 P. 3