Switches

Switches come in 3 main varieties: Pressure, Vacuum, and Temperature. A switch is used to either close or open circuit when it is triggered. This allows units to shut down or engage when the pressure (or temperature/vacuum) hits a certain point.

Common uses include engine shut-off, warning light activation, hourmeter activation, or safety system engagement.

Every switch has a “set-point” at which it will trigger. A set-point is a specific pressure or temperature. When the switch measures that exact point, it engages.

Switches are either “normally open,” “normally closed,” or both "Normally Open and Normally Closed". A normally open switch is an open circuit, while a normally closed switch is a closed circuit. When the pressure (or temperature/vacuum) hits a certain point, metal contacts inside the switch will touch causing the circuit to close which then allows voltage to pass through. A normally closed switch operates in the exact opposite way. A switch that is both normally open and normally closed is simply two separate switches inside the same housing. One terminal on the switch will cease to have voltage, and the other will then become a closed circuit. Switches are available in a variety of different circuit designs. 

 

 

Switches are also known as “rising” or “falling.” A rising switch means that it triggers at its set point and continues to be triggered at any point above it. A falling switch works in the opposite way.

For example, if a normally open rising switch is set to trigger at 15 PSI, and your pressure is 14 PSI or lower, it will not trigger. If the pressure equals or exceeds 15 PSI, the switch will engage. In this case, imagine as if we had wired the switch to a warning light. When the pressure moves past the set point of 15 PSI the switch will close the circuit allowing voltage to the light causing it to shine.

 

Gilmore provides switches from the following manufacturers: Nason, Murphy, GGI, Hobbs, Stewart Warner

Gilmore global Instruments	Murphy
Hobbs	Stewart Warner
Nason

 

If you wish to order, or if you have any questions please feel free to contact us.