Flowserve 90 Series Solenoid Block Kit - Manual (Page 7)

Flow Control Division
Worcester Controls
WCAIM2043 Solenoid Block Kit for Series 90 Modular Accessory System 7
Indications
Actuator/Valve
Failure Mechanism* Failure Symptom Direct-Acting Reverse-acting
SPRING-RETURN LOA VALVE WON’T OPEN Closed N/A
(single three-way) LOP VALVE WON’T OPEN Closed N/A
DOUBLE-ACTING LOA VALVE WON’T MOVE May Rotate N/A
(single four-way) LOP VALVE WON’T OPEN Closed N/A
SPRING-RETURN POSITIONER LOA VALVE WON’T OPEN Closed** Closed
(dual three-way, SR-PC Block) LOS VALVE WON’T OPEN Closed Open
LOP VALVE WON’T OPEN Closed Closed
DOUBLE-ACTING POSITIONER LOA VALVE WON’T MOVE May Rotate May Rotate
(dual three-way, DA-PC Block) LOS VALVE WON’T OPEN Closed Open
LOP VALVE WON’T OPEN Closed Closed
SPRING-RETURN CONTROLLER LOA VALVE WON’T OPEN Closed** Closed
(dual three-way, SR-PC Block) LOS VALVE WON’T CLOSE Open Closed
LOP VALVE WON’T OPEN Closed Closed
SPRING-RETURN CONTROLLER LOA VALVE WON’T MOVE May Rotate May Rotate
(dual three-way, DA-PC Block) LOS VALVE WON’T CLOSE Open Closed
LOP VALVE WON’T OPEN Closed Closed
* LOA – Loss of Air; LOP – Loss of Power; LOS – Loss of Signal
** A pressure switch to detect an LOA condition is required in the M.A.S. unit to make it fail-safe.
1. “May Rotate” means that if one of the actuator chambers has more air in it than the other chamber, the difference in pressure caused by one
chamber bleeding down before the other may cause actuator rotation depending on the torque load on the actuator.
2. For “Open” and “Closed” conditions, “cross-line” mounting the actuator or “in-line” mounting the actuator “upside down” will reverse the
Failure Indication.
For example, a spring-return (single three-way) will go open on loss of power or air if it is set up as a fail-open valve.
3. Direct-Acting means that an increasing input signal will cause the positioner circuit board to drive the valve/actuator in a counterclockwise
(open) direction. (Controller is opposite).
Reverse-Acting means that an increasing input signal will cause the positioner circuit board to drive the valve/actuator in a clockwise (closed)
direction. (Controller is opposite).
3. OPERATION
a. SINGLE-ACTING AND DOUBLE-ACTING ON/OFF TYPE
(POSITIONER/CONTROLLER)
1. Solenoid is ported such that when not energized, the actuator
will be in its closed (clockwise) position.
2. Energizing the solenoid will cause the LED to light and will
provide air to the actuator to open (counterclockwise).
b. SINGLE-ACTING AND DOUBLE-ACTING MODULATING TYPE
(POSITIONER/CONTROLLER) – 120 VAC ONLY
1. Refer to POSITIONER/CONTROLLER Instruction Sheet
(WCAIM2045) for information regarding the operation of the
solenoid valves with these options.
c. FAILURE MODES
See table below.