
Model FS - Wide Differential Float Sensor
- Direct pump control
- Adjustable ON/OFF switching levels
- Unaffected by magnetic fields
- Simple installation.
** If purchasing replacement part, just give us the serial number and we will supply the correct part.**
General Description
The Model FS is a simple float sensor designed for top mounting in open tanks or vessels. The FS can be installed by bulkhead, screw-in or flange mounting. Control range is adjustable from 60mm to 1500mm. This sensor is designed for use as a reliable component in hydraulic units, boilers, magnetic cooling equipment, irrigation systems, etc. The model FS is an economical solution for emptying and filling control.
Operational Description
The model FS consists of a micro-switch operated by a vertical rod and float mechanism. The float freely moves between upper and lower stoppers which are fixed on the rod at the customer's requested points. As the liquid level rises, the float moves up until it reaches to the upper stopper. The rod will then be pushed up by the buoyancy of float, and the micro switch will be operated. When the liquid level falls, the float moves down until it reaches to the lower stopper. Then the rod will be fallen down by the weight of the float, and the micro switch operation will be reversed. A spring mechanism attached to the rod is designed to provide mechanical hysteresis. During the float traveling on the rod, the operating state of micro switch is held until the float reaches the upper or lower stoppers. The stoppers on the rod can be adjusted to obtain desired switching range, and the 5A rated, singlepole, double-throws switch makes the model FS suitable for either empty or full operations.
Installation Notes
Installation of the model FS is extremely simple and easily accomplished. When installing the switch, the following points should be noted:
- The spring operation tension is factory set, but may require adjustment on site, especially if the length of the operating rod is changed. Correct operation should be checked and the spring tension adjusted if necessary.
- It is important that the shaft and rod be mounted so that their axis is truly vertical.
Click on the buttons for full Nohken Specification catalog Sheet and User Manual
Catalog User ManualModel | FS-2S |
---|---|
Application | Open Tank |
Mounting | Equivalent JIS5K50A t=2 |
Contact Rating | 1 SPDT, 250V 5A AC, 125V 0.6A DC (Resistive) |
Operating Temperature - Housing | 0 to 55 ℃ |
Operating Temperature - Wetted Parts | 0 to 80 ℃ |
Float Material | 304SS |
Rod Material | 304SS |
Stopper Material | 304SS |
Flange Material | 304SS |
Bellows Material | Neoprene (Option: Silicon) |
Housing Material | Phenol (Cover: Polypropylene) |
Cable Entry | G3/4 |
Protection* | IP42 |
Minimum SG | 0.85 |
Operating Differential | *60mm to 850mm (at L=1000mm) |
Life Expectancy | 4 x 105 Operations |
* The maximum hysteresis is 60mm, when the float is fixed by two stoppers.
Technical drawing of Nohken Model FS Wide Differential Float Sensor.

For ordering replacement part, please supply full serial number
** If purchasing replacement part, just give us the serial number and we will supply the correct part.**
