Datakom D-700 MK3, User Manual

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D-700 MK3 User Manual Firmware V-16.8
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SELECTING THE CT ACCURACY CLASS:
The CT accuracy class should be selected in accordance with the required measurement precision. The
accuracy class of controller is 0.5%. Thus 0.5% class CTs are advised for the best result.
CONNECTING CTs:
Be sure of connecting each CT to the related phase input with the correct polarity. Mixing CTs between
phases will cause faulty power and pf readings.
Many combinations of incorrect CTs connections are possible, so check both order of CTs and their
polarity. Reactive power measurement is affected by incorrect CTs connection in similar way as active
power measurement.
CORRECT CT CONNECTIONS
Let’s suppose that the genset is loaded with 100 kW on each phase. The load Power Factor (PF) is 1.
Measured values are as follows:
kW kVAr kVA pf
Phase L1 100.0 0.0 100 1.00
Phase L2 100.0 0.0 100 1.00
Phase L3 100.0 0.0 100 1.00
Total 300.0 0.0 300 1.00
➢
Current Transformers must be used for current
measurement. No direct connection allowed.
➢ No common terminals or grounding allowed.