August 2008
95-03076
Page 11
Waukesha Cherry-Burrell
Operation
Operation
All functions of mix proof valves are pneumatically controlled using a 72 to 100
psi (4.9 to 6.9 bar) clean air supply.
The valve contains a large and small spring in the valve actuator. The springs
hold the valve seats in the closed position.
Large Spring
•
Located in the top air chamber of the cylinder.
•
Holds the upper plug in closed position.
Small Spring
•
Located in the extended hub of the upper piston.
•
When the valve is open, the spring only acts on the upper seat stem to hold
the upper and lower plugs together.
•
When the valve is closed, the spring holds the lower plug in closed position.
Solenoid Valve Port
Connections
Typically three air supplies controlled by solenoid valves supply air to the valve
actuator (Figure 5).
The air supply must be 72 to 100 psi (4.9 to 6.9 bar).
ON = Solenoid energized (OPEN).
OFF = Solenoid de-energized (CLOSED).
Solenoids are normally closed.
Air connections are 1/8" NPT.
Figure 6 - Location of Solenoids
Table 1: Solenoid/Valve Position
Condition
Solenoid
3
1
2
Closed
OFF
OFF
OFF
Open
OFF
ON
OFF
Upper Seat
Cleaning
OFF
OFF
ON
Lower Seat
Cleaning
ON
OFF
OFF
Figure 5 - Solenoid Valve Port Connections