Robertshaw Capacitance Level Probes

These probes are used with Robertshaw RF and microprocessor based ON/OFF or continuous level controls for measuring applications involving liquids or granular materials.

When the probe is used with an ON/OFF (fixed level point) type, it may be installed in the vessel in either a vertical or horizontal position. If, however, the probe is to be used on a continuous level measuring application or on an application with a differential (such as Pump On/Pump Off), then it must be installed into the vessel in a vertical position.

Bent probes are available to allow the active length of the probe to be different from the installation direction. See "Bending Specifications."

When the process is a conductive liquid (such as water or sulfuric acid) and the vessel is non-metallic or non-metallic lined, a probe with a ground wire may be employed to provide a ground path to the liquid (second plate).

The liquid must be clean and free of foreign materials and be no more viscous than water.

The Robertshaw Level Measuring instruments have been designed so that they attach directly to the 1/2" NPT fitting on the top of the probe. Typically, these are either the complete transmitter housing or a conduit outlet box with a coaxial cable to the instrument. The 6-32 threaded fitting in the end of the probe rod accepts either a contact pin or a machine screw as required.

These high pressure/temperature non-insulated probe assemblies utilize a one piece gland construction and ceramic insulator bushings so as to withstand cyclic as well as continuous high pressures. Primary sealing surfaces are maintained under compression by spring washers.

Sealing, for both liquids and gasses, is accomplished by the use of high temperature o-rings. The o-ring material is suitable for use with most products.

Positive retention of the probe rod in the gland is provided by a bushing which prevents the rod from coming through the gland even under pressures in excess of rated pressure.

The flexible version has a fitting swaged to the stainless steel cable. This fitting is threaded into the gland assembly.

Intended for severe pressure and/or temperature service these non-insulated probes may be used with the Level-Tek, Level-Tel, Level-Lance or Excalibur 7000 in nonconductivematerial applications.