SRP Rotary Paddle Level Switch

The SRP Series rotary paddle point level sensor is a point level indicator used for high and low level alarm to detect the presence and absence of materials within bins, hoppers and silos containing powder and bulk solids. The level point sensor is mounted on the top or the side of a bin to prevent bin overflows and material outage. A robust synchronous motor drives the shaft and the chosen attached paddle rotates freely in the absence of material. As material comes in contact and impedes the paddle rotation, two limit switches internal to the assembly will be activated. The first limit switch disconnects power to the motor to prolong the life of the motor and save power; the second limit switch changes the state of the output relay contacts. As material falls away from the paddle, the state of the output relays changes and power is applied to the motor and rotation of the paddle resumes. In addition, the adjustable time delay provides a 0-12 second adjustment to eliminate nuisance alarms due to shifting and surging materials.


Plastics and synthetics
Chemicals and fertilizer
Food and beverage
Agriculture and fodder mills/depots
Cement and Aggregates
Power plants
Various incinerators

Universal 20-250VAC/VDC power supply
10-28VDC version available, with an adjustable on/off time delay
Local LED indication (some versions)
Unique seal for pressure up to 58psi (4bar)
Fail Safe Mode FSH/FSL Switch selectable
Easily adjusted sensitivity, no disassembly required
Automatic motor shutoff extends motor life
Remote test function (some versions)
Bin temperature up to 392⁰F (200⁰C) available

Power Requirements: 20~250VAC/VDC, 50/60Hz, 10-28VDC version available
Output: Relay: 5A @ 240VAC/28VDC, NPN/PNP: 400mA @ 60VAC/VDC, or Microswitch: 6A @ 250VAC
Process Temp: Up to +392°F (200°C) for high temperature models
Process Pressure: 58 PSI (4 bar)
Enclosure Rating: NEMA 4X / IP65
Process Connection: 1-1/4” NPT
Conduit Connections: Two 3/4” NPT