Robertshaw Capacitance Level Probe
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.
Model 150KB284 and 150KB285 Non-Insulated High Temperature/Pressure Probe
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. Pressure sealing surfaces are maintained under compression by parallel spring washers.
On the 150KB284 (flexible) model, the stainless steel flexible cable has a swaged threaded termination for connection into gland assembly.
On the 150KB285 (rigid) model, positive retention of the probe rod in the gland is provided by a boss which prevents the rod from coming through the gland even under pressures in excess of rated.
Intended for severe pressure and/or temperature service, these probes may be used with either the Level-Tek, Level-Tel, Level-Lance or Excalibur 7000 in non-conductive material applications.