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7. Pump protection & cooling water flow

It goes without saying that pumps should never run dry to ensure their proper operation and prevent unnecessary wear and tear of critical and expensive hardware.  Additionally, minimum flow rates for cooling water flow should be achieved prior to and throughout operation of rotating equipment.

For this reason a sensor is placed in the line to detect liquid movement. Within seconds of pump startup, the sensor confirms liquid is flowing or the pump is automatically shut down and the appropriate alarm initiated to prevent any damage. This is known as a ‘flow/no flow’ pump application. 

Rotating equipment such as pumps, generators and machine bearings generate lots of heat.  Water and lubricants are circulated through heat exchangers to remove heat and provide sufficient cooling for rotating hardware.  Leaks in water cooling water distribution or underperforming pumps will diminish cooling capacity and eventually result in overheating and damage to bearings.


The Thermatel TD1 or TD2 is an excellent device for ‘flow-no flow’ pump applications as well as to check adequate flows of cooling fluids.

  • Temperature compensated to provide repeatable alarm under varying process temperatures
  • Continuous diagnostics detect sensor fault
  • Non-linear mA output signal can be used for trending, diagnostics and repeatable flow/level indication (TD2)
  • Detects minimum flow or presence/absence of flow
  • Easy/fast calibration
  • Excellent low flow sensitivity
  • Flow, level & interface detection