Ross Controls 2_2 WAY WITH PRESSURE RELEASE SERIES 27 - Manual (Page 3)

4 © 2009, ROSS CONTROLS ® . All Rights Reserved.
Dual Internal Pressure Controlled PO Check Valve Applications
Remote Trapped Pressure Relief Manual Trapped Pressure Relief
V1 V2
3-Position, Open-
Center Control Valve
Cylinder
L-O-X®
Valve
Flow
Control
Valves
Dual Check
Valve with
Internal Pilot
C1 C2
B A
Manual-controlled
Check Valve relief
V1 V2
3-Position, Open-
Center Control Valve
Cylinder
L-O-X®
Valve
P
Holding
Pressure
Flow
Control
Valves
Dual Check
Valve with
Internal Pilot
C1 C2
Remote-controlled
Check Valve relief
CIRCUIT FEATURES:
• Trapped pressure between check valve and cylinder is exhausted
when the air supply at “P” port is lost or locked-out.
• Cylinder moves as long as a control valve solenoid is energized.
Use for continuous motion or jogging.
• Cylinder remains stationary if neither control valve solenoid is
energized, or if electrical signal is lost.
• L-O-X ® valve provides lockable shutoff of air supply, and
exhausting of trapped downstream air.
IMPORTANT NOTES and CAUTIONS:
» Cylinder movement may occur when inlet pressure is lost. Its
movement is slowed only by the restrictions of the flow control
valves, and by the exhaust capacity of the check valve relief flow
capacity.
» For best response, flow control valves should be installed
between the check valve and the cylinder.
» Pressurizing the system after supply air has been off may
cause rapid movement of the cylinder because cylinder air
was exhausted while the supply air was off. See page 5 for
soft-startup circuit.
CIRCUIT FEATURES:
• Trapped pressure between check valve and cylinder is
exhausted when pushbuttons A and B are pressed.
• Cylinder moves as long as a control valve solenoid is energized.
Use for continuous motion or jogging.
• Cylinder remains stationary if neither control valve solenoid is
energized, or if electrical signal is lost.
• L-O-X ® valve provides lockable shutoff of air supply.
IMPORTANT NOTES and CAUTIONS:
» Cylinder movement may occur if only one pushbutton (A or B)
is pressed. To exhaust fully both cylinder ports, push and hold
A and B simultaneously.
» For best response, flow control valves should be installed
between the check valve and the cylinder.
» Pressurizing the system after supply air has been off may
cause rapid movement of the cylinder. See page 5 for soft-
startup circuit.
L-O-X (Lockout
& eXhaust Valve)
3-Position, Open-
Center Control Valve
Single PO Check Valve
Vertical
Cylinder
Single Pressure Controlled PO Check Valve Application
CIRCUIT FEATURES:
• Trapped pressure between check valve and cylinder is exhausted when the
air supply at the Blowdown Signal Port (BP) is lost or locked-out.
• Cylinder moves as long as the control valve solenoid is energized. Use for
continuous motion or jogging.
• Cylinder remains stationary if neither control valve solenoid is energized, or
if electrical signal is lost.
• The single PO check with pressure relief have an additional 1/8” NPT port
provided for the installation of a pressure sensing device such as a pop-up
indicator or pressure switch. Standards suggest that machine design should
include a method for verifying the release of stored energy.
IMPORTANT NOTES and CAUTIONS:
» Cylinder movement may occur when inlet pressure is lost. The cylinder’s
movement is slowed only by the restrictions of the flow control valves, and
by the exhaust capacity of the check valve relief flow capacity.
» For best response, flow control valves should be installed between the check
valve and the cylinder.
» Pressurizing the system after supply air has been off may cause rapid movement
of the cylinder because cylinder air was exhausted while the supply air was off.
With Trapped Pressure Relief
TYPICAL APPLICATIONS:
Horizontal or vertical long-stroke cylinders.
NOTE: See Installation and Troubleshooting on page 6.
TYPICAL APPLICATIONS: Horizontal or vertical long-stroke cylinders.