Tiny switch handles high pressure and temperature

Edited by the Engineeringtalk editorial team Apr 28, 2004

The ELS-900 electro-optical level sensor is only 35mm long, but is capable of operating accurately at pressures up to 17bar and temperatures up to 125C.

The new ELS-900 electro-optical level sensor from Gems Sensors is only 35mm long, but is capable of operating accurately at pressures up to 17bar and temperatures up to 125C.

In addition to this market leading performance, the ELS-900 is compatible with a wide range of fluids and features very economical pricing.

The smallest electro-optical switch available with integral electronics, the ELS-900 offers all the benefits of Gems prism technology.

The prism-shaped tip of the sensor eliminates droplet formation and false alarm trips, which means that the sensor can be used in a wide range of liquids that sensors using other technologies cannot handle.

The extremely high pressure and temperature capabilities of the sensor, combined with its very small size, open up a host of new applications in industries as diverse as medical, food, semiconductors, hydraulics, machine tools and engineering.

For example, the sensor could be used to monitor coolant levels in diesel generators, its high temperature resistance allowing it to be placed directly in the radiator rather than in the overflow bottle.

Other potential applications include low lubricant warning on machine tools and on- or off-highway vehicles and low-level warning in hydraulic reservoirs.

The housing of the ELS-900 is polyethersulphone, with no metallic components in contact with the liquid being measured.

As well as having high temperature resistance, polyethersulphone is FDA and NFS approved, making the sensor ideal for use in medical, electronics, pharmaceutical, beverage and food processing applications that operate at high temperatures.

Examples include low-level warning in the hot deionised water systems used to rinse semiconductor wafers after etching, and high-level warning in distilled water stills.

Very economically priced, these switches feature built-in solid-state electronics.

They are also extremely reliable, as they have no moving parts.

Repeatability is +/-1mm and the ELS-900 is suitable for operating temperatures from -40 to +125C and pressures from 0 to 17bar(g).

Three types of mounting are available: M12 x 1.8 and 0.5in-20 SAE 5, 0.25in NPT.