ITT NEODYN PRESSURE SWITCH

Pressure Switch

ITT is a focused multi-industrial company that designs and manufactures highly engineered critical components and customized technology solutions. Our customers in the energy, transportation and industrial markets depend on us to solve their most critical problems, and we focus on partnering with them to find solutions to their unique challenges. Founded in 1920, ITT is headquartered in White Plains, N.Y., with employees in more than 35 countries. The company has sales in approximately 125 countries.

Unlike most other pressure and temperature switches, ITT Neodyn switches are negative rate type switches (i.e. Belleville spring) which are snap acting devices. At a certain pressure (apex of the spring curve) the spring snaps over center. At this point, it takes less 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. ITT Neodyn Temperature switches operate in a similar way via the expansion pressure of the liquid filling within the temperature probe.

Advantages of the Nega-Rate® Belleville Disc Spring Switches

STABLE SET POINTS - “Eliminates Constant Recalibration” BECAUSE:
• No moving parts except during actuation—no spring fatigue or wear.
• Set point is mostly a function of the negative rate Belleville spring—variables in snap action electrical have little effect on the set point.
• Total movement of the Belleville spring compensates for any relocation of the electrical due to case growth - consistent set point over temperature change.
• No linkage utilized—no wear which can affect accuracy.

VIBRATION RESISTANT - “Eliminates Contact Chatter”BECAUSE:
• Belleville spring does not preload the electrical prior to actuation—snap action electrical maintains its vibration
resistant characteristic.
• Small mass and inherent stability of the Belleville spring resists chatter caused by vibration.
• Snap action electrical is ruggedly mounted with minimal bracketry—no spring mounted electricals or linkages.

HIGH OVER-PRESSURE CAPABILITY - “No Affect on Set Point Accuracy” BECAUSE:
• Belleville spring does not contain the pressure—no affect on system or proof pressure capability.
• The pressure sensing portion bottoms out after actuation and is fully supported—pressure sensing parts are designed for high pressure conditions.
• Limited movement of spring mechanism—no overtravel of the snap action electrical due to high pressure.

HIGH CYCLE LIFE - “Millions of Cycles” BECAUSE:
• Short stroke minimizes wear—Belleville spring mechanism is exercised less than .020".
• Snap action of Belleville spring reduces electrical arc—prolongs contact life