Operation
Waukesha Cherry-Burrell Brand W71/W72RS Sch. 5 Mix Proof Valves
Page 18
95-03091
08/2018
Automatic Fail-Safe
System
WCB 2-Piece Control Top
W71
W72RS
Valve Stem Detection Condition
Upper
Sensor
(NO)
Lower
Sensor
(NC)
Upper
Sensor
(NO)
Lower
Sensor
(NC)
Sensor Symbol
Valve Closed
0
1
0
1
Valve Open
1
0
1
0
Valve Closed with Upper Seat Clean *
0
1
0
0
Valve Closed with Lower Seat Clean *
0
0
0
1
Bürkert 8681 Control Top
All W70 Series Valves
Valve Stem Detection Condition
S1
S2
S3
S4*
Valve Closed
1
0
0
0
Steady Red
Valve Open
0
1
0
1
Steady Green
Valve Closed with Upper Seat Clean
1
0
0
1
Fast Flashing Green
Valve Closed with Lower Seat Clean
0
0
1
0
Slow Flasing Green
CU4 Control Top
W71
Valve Stem Detection Condition
Open Sensor
(Upper)
Closed Sensor
(Lower)
Valve Closed
0
1
Valve Open
1
0
Valve Closed with Upper Seat Clean
0
1
Valve Closed with Lower Seat Clean
0
0
1 = Energized, LED is lit; 0 = De-energized, LED is off
Upper Sensor: Sends an input signal when the valve is properly open.
Lower Sensor: Sends an input signal when the valve is properly closed.
Additional Sensor: A third yoke-mounted proximity sensor is available for additional signal feedback.
* W71 Valves: Seat lift during both upper and lower seat clean; indicator stem raises;
W72RS Valves: Seat lift during upper seat clean; seat push during lower seat clean, indicator stem lowers.
1 = Feedback; 0 = No Feedback
*
Normally Closed External Proximity Sensor; LED is opposite of feedback signal.
1 = Feedback; 0 = No Feedback
Top LED Indication
Summary of Contents for W71
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