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Float Switch FAQs


What is a pump switch?

Pump switches are designed to directly control a pump. Because they directly control a pump they have higher amp ratings so they can withstand startup and running current. The FLA (full load amps) of the pump runs through the switch.

What is a control switch?

Control switches monitor high or low level liquid conditions to activate control panels and alarms. They are narrow angle switches designed for a shorter range of travel and will engage or disengage with very little vertical movement. For example, a control switch used at the high level in a pump down application turns on when the float is slightly above horizontal and turns off when the float is slightly below horizontal. Control switches have smaller wire and are not designed to handle the direct amperage of a motor. They send a signal to an alarm or motor contactor, have a lower amp rating, and should never be wired directly to a pump.

What does pump up mean?

A pump up switch is used for filling in water and sewage applications. A pump up switch has normally closed contacts, meaning the contacts are closed when the float switch in hanging down.

What does pump down mean?

A pump down switch is used for emptying in water and sewage applications. A pump up switch has normally open contacts, meaning the contacts are open when the float switch is hanging down.

What is normally open?

If a pump switch is “normally open” the contacts are open when the float switch is hanging down. Normally open switches are used for pump down applications.

What is normally closed?

If a pump switch is “normally closed” the contacts are closed when the float switch is hanging down. Normally closed switches are used for pump up applications.

What is a piggyback float switch?

A piggyback float switch will plug into a power outlet. The back of it’s plug will have an outlet to plug in the pump.

What is a vertical switch?

Vertical float switches are used in applications with limited space. Float travels up and down on a fixed vertical rod.

What is a diaphragm switch?

A diaphragm switch is activated by pressure. They are often used in applications where a float may hang up.

What is a tethered float switch?

A tethered float switch is typically tethered to the pump or the discharge pipe. A tethered float is great for a larger basin and will allow for a longer pump run time.

Do you sell mercury float switches?

Yes, we currently sell mercury float switches. However, an increasing number of areas are restricting the sale of products containing mercury. We offer many mechanical alternatives for mercury switches.

Do you have other questions about float switches that we have not answered? Call us today at RC Worst & Company.