The grounding points on the frame of the electric machine are for safety grounding, and
signal cables and power cable shields have their own grounding points.
The machine enclosure grounding point, safety grounding
Testing the power cable shield grounding (earthing)
The power cable shields are grounded (earthed) through the cable glands to the connection box and
further to the electric machine enclosure. After the cable gland assembly and power cable installations,
and any time when needed, make sure that the grounding (earthing) connections are correct.
1. Connect one terminal of the measurement device to the cable shield of one power cable (in the
inverter end of the cable)
2. Connect the other terminal of the measurement device to the cable shield of an other power cable.
You can also use the machine enclosure grounding point for the measurement.
3. Measure the resistance between the two cable shields or between the cable shield and the enclosure
grounding point.
4. Change the measurement device terminal(s) to the shield of different power cable and repeat the
measurement until all cables have been measured.
Testing the low voltage (measurement signal) cable shield grounding (earthing)
The low voltage (measurement signal) cable shield is connected to the grounding (earthing) point. After
cable installation, and any time when needed, make sure that the grounding (earthing) connection is
valid.
1. Connect one terminal of the measurement device to the low voltage cable shield (in the non-
machine end of the cable).
2. Connect the other terminal of the measurement device to the machine enclosure grounding point.
3. Measure the resistance between the cable shield and the enclosure grounding point.
User Guide
EM-PMI375
Installation
©
Danfoss | November 2021
BC265856307805en-000202 | 55
