CT Lab Impedo DUO, User Manual

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Impedo DUO User Guide
95
6.2.4.2 110 V Voltage Transformer (VT) Circuits & 400V Direct (Star/ 4-wire
systems)
Always connect the safety earth terminal located on the power
connector first!
Table 11: VT circuit connection layout for 4-wire star connection
Terminal Legend 110V VT Circuit or 400V/550V Star (4-wire) Systems
1. V
1
Phase 1
2. V
2
Phase 2
3. V
3
Phase 3
4. V
com
Neutral (Star connection point)
5. V
4+
Earth (optional for 400V systems only)
6. V
4-
Star connection point (Neutral) (Optional for 400V
systems only)

Connect Phase 1,2 and 3 to Voltage Inputs 1-3 as shown in Figure 62 below.

Connect Neutral (400V systems) or the star-point (110V VT circuits) to V
com
.

The fourth voltage input may be used on 400V systems to measure Neutral-
Earth voltage.
Figure 62: Impedo Duo 4-wire star connection
Phase 3
Phase 2
Phase 1
Phase 4 Ref
Phase 4
Neutral