One of the most integral parts of a pumping system is a float switch. Float switches are used to monitor liquid levels in a basin, tank, or cistern of a pumping system. The float switches send signals to pumps, control panels, or alarms based on changing levels of the liquid. There are many different options available, however, one of the important differences is whether your system requires a pump or a control float. Simply put, a pump switch will directly control your pump and a control switch will send signals to a control panel or alarm. The control panel, in turn, sends signals to the pump.
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. Typically, a single pump switch in a pump down application turns on when the float is 45 degrees above horizontal, signaling a high level, and turns off when the float is 45 degrees below horizontal, signalling a low level. Pump switches normally have a wider angle of travel than a control switch. The tether on the pump switch can be adjusted to increase or decrease the pumping range. The longer the tether, the more travel the switch will have. Pump switches are offered without a plug for direct wiring or with a piggy-back plug. A single pump switch can be used in place of two control switches in order to limit the number of floats in a system. For example, a single pump switch in a pump down application installed with a longer tether can be used instead of two control floats (one for on at high level, one for off at low level). It is important to point out that the pump switch is more susceptible to getting caught up as it has a longer range of travel.
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.
Looking for that peace of mind of having your pumping system working properly? Call us today at RC Worst & Company to discuss the right float switch to meet your needs.