Current transformer

The ratio of the current transformers used is required to be able to determine the measured values correctly.

Settings

• Measuring mode (absolutely essential for three-wire systems)

• Voltage reference

• Swap s1(k) and s2(l)

• Measurement group mode for L1..L4 *

• Current channel L1-L3

• Current channel L4 *

• Multifunction channel L5 *

Measuring mode (absolutely essential for three-wire systems)

• Click on a current channel in the device image.

• Specify the measuring mode:

  • The Current measurement setting corresponds to 3w2u for three-wire and is also correct for four-wire and 3 x L3 measuring.

  • The setting Calculated (Aron measuring circuit) corresponds to 3w2u for three-wire.

Voltage reference

If you have swapped the current channel (e.g. L1 and L3 swapped), you can correct this here.

Swap s1(k) and s2(l)

If you have connected the current transformer of this channel incorrectly, you can correct this here.

Example image: UMG 96-PQ-L

Measurement group mode for L1..L4 *

• Select Current measurement Low power for small-signal current transformers or active Rogowski coils with an integrator circuit.

• Select Current measurement Rogowski passive to switch on the integrator circuit in the measurement device for passive Rogowski coils.

Example image: UMG 96-PQ-L-LP

Current channel L1-L3

The current transformers for channels L1 to L3 must have the same transformer ratio.

• Select only the checkbox Current Channel L1-L3 .

• In the Primary and Secondary fields, enter the current transformer ratio according to the specification on the rating plate of the current transformer.

Example image: UMG 96-PQ-L

Current channel L4 *

• Select only the checkbox Current Channel L4.

• In the Primary and Secondary fields, enter the current transformer ratio according to the specification on the rating plate of the current transformer.

Multifunction channel L5 *

If Measuring mode = DC power is selected for the channel (terminals 29+30), enter the current transformer ratio here.