Senders are available in a series of lengths from 150mm - 1600mm.

There are two standard resistances, 0-190 ohm, used mainly in European gauges and 240-30 ohm used by American gauge manufacturers. Senders and gauges must have the same resistance range.

The Wema S3 Fuel and Water Sender is also suitable for use as in oil and many other liquids. (contact us for confirmation if using for unusual use) 

Robustly made from 316 stainless steel and fitted as original equipment for over 30 years by all the major British and European boat builders, our fuel and water senders still work on the simple principle of twin magnets in the float tripping a series of reed switches securely housed, and doubly insulated inside the stainless tube.

Over the years senders have been improved with advances in reed switch technology, allowing us to fit far more switches inside the senders, giving the better resolution required by modern digital displays.

We now offer high-resolution senders from 150mm to 400mm.  These senders are the same as the standard-resolution in every way except we have placed the switches at ~every 10mm instead of ~every 20mm giving you more accuracy and clarity in the shallowest of tanks.

The S3 senders have proved very reliable and this Wema technology is used by all major European truck and bus manufacturers and on many off road and military vehicles.

Longer senders and bespoke options are also available including different outputs; 0-5v, 0-10v, 4-20ma... Please get in touch to find out more. 

The Wema S3 Fuel and Water Sender can also be used as a position sensor; mounting the sender to one part and clamping the float to the other moving part. 

[Please note: the code 001300 refers to the S3 head]

Torque Settings

Use these torque settings when screwing the S3 sender (with o'rings mounted) into a flange:

Steel Flange:  9 ± 1 Nm
Nylon Flange:  7 ± 1 Nm