Midland-acs Pressure Switches and Quick Exhaust Valves: Selection and Setup
Midland-acs Pneumatic Components at a Glance
Midland-acs supplies compact pneumatic controls including pressure switches and quick exhaust valves. The 2PS3SL102 is a diaphragm pressure switch for setting trip points on air or inert-gas lines, while the 2QEVSE122 quick exhaust valve dumps actuator exhaust locally for faster cycle times. Together they form a typical local air-control package.
Selecting a Midland-acs Pressure Switch
- Pressure range: Choose a range where the trip point sits in the middle 20–80% for best repeatability.
- Electrical rating: Match the contact type (SPDT/SPST) and voltage/current to the PLC or relay it drives.
- Port and media: Confirm the process connection (typically G1/8–G1/4) and that the diaphragm material suits the gas.
- Adjustment: A screw or knob sets the setpoint; some versions add a deadband control for hysteresis.
What a Quick Exhaust Valve Does
A quick exhaust valve (2QEV) sits close to the actuator. On exhaust, it opens a large local port to atmosphere so the cylinder retracts or extends far faster than if the air had to travel back through the directional valve and tubing. Benefits:
- Up to 2–3× faster stroking on long lines.
- Lower air consumption and reduced valve wear.
- Simpler plumbing — one exhaust port instead of routing back to the manifold.
Installation Best Practice
- Mount the pressure switch away from vibration and heat sources; use a snubber for pulsating lines.
- Place the quick exhaust valve as close as possible to the actuator port — distance defeats the speed gain.
- Set the switch setpoint with the system at operating pressure, then verify on/off with a gauge.
- Keep exhaust ports clear of debris and directed away from personnel.
Maintenance and Troubleshooting
Pressure switches may drift if the diaphragm ages — recalibrate annually on critical loops. A quick exhaust valve that hisses continuously usually has a worn seat; replace the cartridge. Neither device needs lubrication if the air is properly filtered and dried (40 µm filter, dew point below ambient).