ITT Aerospace Controls

Neo-Dyn Low Pressure / Vacuum Switches Series 142P/180P/181P/182P

A negative rate type pressure switch (i.e., a Belleville spring) is a snap acting device. At a certain pressure (apex of the spring curve) the spring snaps over center. At this point, it takes pressure (force) to continue its movement. The pressure switch set point is a function of the Belleville spring. The electrical switch is in a fixed position and is synchronized to the movement of the Belleville. The Neo-Dyn switches feature a negative rate Belleville spring snap acting device which offers greater set point stability, vibration resistance, over-pressure capability and cycle life.

IEC 61508     SIL 3

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Last Updated: Wed, January 08, 2020