Frquently Asked Questions

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What is an isolation valve?

A diaphragm is used to isolate media from the over seat parts of the valve, reducing media contact with the valves internal components. This is suitable for aggressive liquids or gases and helps reduce the risk of media contamination.

What is a latching valve?

A latching valve is designed to allow the valve to stay either open or closed without continuous power.

What is the response time on a Gems solenoid valve?

Response time is application specific but as a general rule use 5ms for the E,F,G series and 10-20 ms for the A,B,C,D series.

What does MOPD stand for?

Maximum opening pressure difference across the valve.
Gems solenoid valves range from 0 to 1000 PSI

What is the standard operating temperature on a Gems solenoid valve?

-40°F to 212°F / -40°C to 100°C
Cryogenic valves are rated to -320°F / -196°C

What is the difference in the coil classifications?

Gems have 3 class options, each having a different maximum operating temperature. Be aware that valves left on for 5 to 10 minutes will self-heat. A typical 6 watt “A” valve will self-heat to 60°C while a 10 watt “D” valve will self-heat to 90°C

Class B 266°F / 130°C
Class F 311°F / 155°C
Class H 365°F / 180°C

Does Gems Sensors do customized valves?

Yes, for qualified OEM applications. Together with your design team, Gems’ engineers can customize the best solution for your application.