So that the sensor part of the probe is within the specified distance required to properly monitor the process and accurately provide feedback to the PLC, DCS, or other control equipment.
If it is not within the specified gap the sensing operation will not be accurate and the process system controls will not function correctly.
Depending on the application, the result could be catastrophic to humans and equipment.
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They said; "Brain size?" I heard; "Train size?" so I said: "I'll take a small one, thank you."
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