NT210K + TPL503 Temperature Pressure and Level Monitor

The NT210 K controller combined with the TPL503 sensor provide the highest level of protection for hermetic oil filled transformers.  The TPL503 replaces the classic electromechanical controls of the past and is installed directly on the transformer via an integrated flange allowing it to monitor the oil temperature, pressure and level.  The sensor has a transparent body which allows you to see the oil level from any direction around the sensor, making it easy to visually check the oil level.  Sensor data is transmitted to the NT210K controller via an RS485 serial connection.  This allows the control of all measurements and indications remotely.  A self-test circuit reports any anomalies with the sensor or the controller, ensuring that your hermetic oil-filled transformer will never be alone!

On request, a protective coating can be applied to the electronics board for tropical climates.


  • Temperature monitoring from 0°C to 120°C (32° – 248°F)
  • Pressure monitoring from -400 to +500mbar (-5.8 to +7.25psi) (Control from 0 to +500mbar)
  • Level control in 3 modes:  FULL, ALARM, TRIP
  • 24-240VAC -DC input power
  • VDC with reversible polarities
  • Rated for use in ambient temperatures from -20° to +60°C (-4° to 140°F)
  • Digital input (RS485) for connection to TPL503 sensor
  • All potential free output relays rated for up to 5A @ 250VAC
  • 2 alarm relays (Alarm & Trip)
  • 1 alarm relay for sensor or self diagnostic fault
  • 1 alarm relay for fan control
  • Power-link output (9VDC) to power the TPL sensor directly from controller

The TPL503 sensor monitors oil temperature, pressure and level