Normal Positions of Float Switches
A glass reed switch is hermetically sealed inside the stem from the liquid environment.
“Normal” float position means the fitting and wires are on top and the float is resting at the bottom of its travel range (not floating on liquid)
The changing level of the liquid moves the float up and down the stem.
Standard Vertical Fluid Switches can operate as Normally Open (NO) or Normally Closed (NC) by flipping the float 180° on the stem.
Part D is the float, with the dark black boxes representing the magnet. Part B is the sensor. The sensor outputs a signal when the magnet is aligned with it. Part I, the clips, are aligned such that the operation of the float matches the required criteria. This example image shows NC or normally closed. When the float is resting on the bottom clip, the magnet is aligned, thus the signal can pass. When the float raises, the magnet is no longer aligned and no signal can pass. In this case, the bottom clip is critical as the magnet needs to align with the sensor for the output to be normally closed. The top clip can be anywhere above the sensor along the tube (Part G) as long as the magnet is no longer aligned with the sensor.
If we flip the float as seen in the next image below, we can achieve a normally open or NO operation where the signal passes when the float rises. Now the top clip becomes critical, as the float must stop in a position where the magnet is aligned with the clip. The bottom clip can be located anywhere along the tube, part G, as long as the magnet is not aligned with the sensor.