Clearance Requirements for Probe and Transmitter Installations

Clearance Requirements for Probe

The nature of Guided Wave RADAR requires a 4” minimum diameter around the probe to be free of metal. The probe must be mounted at least 2” away from any internal pipes, fittings, and structural members. In-feeds, weirs, drains, and agitators may cause mechanical damage to the probe. They will also create turbulence that causes incorrect level measurements. The probe must be mounted as far as possible from turbulent areas of the tank.

The image below highlights three different probe installation examples and what to look out for when deciding where to install your probe. 

#1. The probe is too close to the side of the tank (or other fittings) 

#2. The probe is too close to the tank infeed 

#3. The probe is placed correctly. There is no interference within 2" of the probe

Clearance Requirements for Transmitter

The image below shows the top of the probe installed inside your tank. The 6" clearance on either side of the top of the probe and any manway, piping, etc. is to ensure adequate room for the TD transmitter and wiring.