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Liquid Level Switches

General Information & Features

Rochester liquid-level switches utilize magnetic reed switches hermetically sealed inside capsules. Depending upon the switch model, the reed switch may act alone or trigger solid-state devices at the required point through magnetic actuation by a high-strength drive magnet located in the head of the liquid-level gauge


Data Sheet

Instruction Sheet - DS-889

Mark Part # Calib. Switch Max
Construction Application
5S23 5023S00778 LH S.P.S.T. 140 VAC
50 VDC
0.5 resistive 10 Reed Switch Only Low current circuit
5S254 5254S00778 RH
5S255 5255S00778 240 VAC
500 VDC
0.5 small inductive High Voltage Reed Switch
5S24 5024S00778 LH
or RH
S.P.D.T. 125 VAC
28 VDC
0.25 resistive 3 Special S.P.D.T. Reed Switch High/low signal with very narrow overlap
5S248 5248S00778 RH S.P.S.T. 240 VAC
AC Only
1.0 inductive 75 Low Amp Triac Medium current circuit
5S80 5080S00778 LH 2.0 inductive 300 at
230 V
HV Reed Switch and M.O.V. transiet suppression High current circuit
5S149 5149S00778 1.0 inductive 150 at
230 V
HIgh Voltage Reed Switch
and Triac
Medium current circuit


The liquid-level switches shown on the preceding page are suitable for use with the following Rochester models:

M6250 6453 7553 L8453
LM6253 L6453 8450 8550
M6253 7550 8153 8553

All standard switch gauges have Senior heads for mount­ing on a 2 1⁄2" [63, 5 mm] bolt circle, and are furnished complete with four mounting screws and a mounting gasket. See Rochester brochure, 22 Series Adapters, for the available mating-tank adapters.

All LH calibrated switches are mechanically and magnetically interchangeable with all other LH calibrated switches. The same is true for RH calibrated switches. All “AC only” switches are intended for AC only as these devices will open circuit only when the voltage cycle passes through zero.

How to Order*

Select the switch and switchgauge most suitable for application. Typical applications are shown above.

When Ordering Specify:

1. A, B, C, D and H tank diameters.

2. Type of liquid and working pressure.

3. Electrical requirements and type of operation (to close or open at special level).

In all cases, a sketch or drawing of your particular application will help ensure your needs will be accurately and completely understood.


Note: For installation instructions see DS-889 (available upon request).


*Materials and specifications are subject to change without notice. Pressure ratings subject to change due to temperature and other environmental considerations.