MR MESSKO COMPACT - Connecting Current Transformer

6 Installation and commissioning
875831400/02 EN
2. If a constant temperature cannot be ensured, we recommend taking the
temperature sensor out of the thermometer pocket and placing it in a ther-
mometer calibration bath. Set the calibration bath to a temperature of
40°C for this example.
3. Connect a current source to terminals 3 and 6 of the thermometer. Set the
nominal secondary transformer current specified by the transformer man-
ufacturer (e.g. 1.9A) on the current source.
4. Wait until the temperature display stops changing (approx. 15minutes).
5. Compare the temperature display to the previously calculated value (in
this example, 40°C + 26K = 66°C).
6. If the required temperature value is not reached on the thermometer dis-
play, use the adjustment screw of the potentiometer to readjust (take the
heating and cooling time of approx. 15minutes into account).
7. If the displayed temperature remains at the required value constantly over
a period of 30minutes, the calibration is complete.
8. Reinstall the temperature sensor in the thermometer pocket.
6.7 Connecting the current transformer (winding temperature)
WARNING
Electric shock!
Dangerous high voltages may occur when a current trans-
former is operated with an open secondary circuit. This can
lead to death, injuries and property damage.
► Make sure that there are no dangerous electrical voltages on the CT
secondary circuit.
► Never operate a current transformer with an open secondary circuit;
short-circuit the current transformer to prevent this.
► Ground the current transformer on one side.
► Observe the information in the current-transformer operating instruc-
tions.