FM10-SMD, Preconfigured, Dual Level Liquid Sensors
SMD Sensors is now offering pre-configured, dual level switches made with stainless steel material. These units are typically in stock and are readily available.
The FM10-SMD** series of switches range in overall lengths from 4” to 12” and come in either internal or external fittings for mounting to your tank. See datasheet for more details.
Up to 18 configurations to choose from; FM0-SMD01 through FM10-SMD-18 are configured with either both Upper and Lower Levels are Normally Open (NO) or Normally Closed (NC) contacts
- Normally Open = Pump Down
- Normally Closed = Pump Up
FM0-SMD Switches are Ideal for Pump up or Pump down applications (see Pup/Pdn PDF)
A Pump-Up Float Switch, also known as ‘Normally Closed’, opens the circuit on the rise and is typically used to turn the pump off when the float is in the up position. So, a pump could be set to turn off when the water level in the storage tank reaches a predetermined high level. Therefore, a pump-up float switch is often used to fill a water tank.
A Pump-Down Float Switch, also known as ‘Normally Open’, closes the circuit on the rise and is typically used to turn the pump off when the float is in the down position. So, a pump could be set to turn off when the water level in the storage tank reaches a predetermined low level. Therefore, a pump-down float switch is often used to empty a water tank.