Mechanical pressure switch 100 series

differentialNCNO

• NON-BLEED IN EITHER SWITCHED STATE These switches were designed for use on monitoring systems associated with natural gas transmission. Typically the switch can be used to protect a system or pipeline from an abnormally high or low pressure which might result in the discharge of gas. The switch has an integral 2-port changeover valve connected to a regulated natural gas supply. As the switch operates the output of this valve changes between the regulated supply pressure and zero. This output can be used to control the operation of a valve which would then isolate the system. For low pressure switching the output valve would typically be configured as normally closed (N.C.) to give an output above the set-point of the switch. This output is lost as the process pressure falls below the setpoint. For high pressure switching the output valve would typically be configured as normally open (N.O.) to give an output below the set-point of the switch. This output is lost as the process pressure rises above the setpoint.