Contrel EMA-90N - Page 5

EMA‐90N UserManual IM128‐Uv0.74 Pag.5/32
In case of connection in a 3 phase network (without neutral or with
neutral not distributed) don’t connect the N terminal.
WARNING: If the instrument has the TTA on the current inputs,
DON’T connect the S2 terminals to the earth.
This connection with only 2 CT (and eventually 2VT) allows to
measure accurately the three-phase currents.
WARNING: If the instrument has the TTA on the current inputs,
DON’T connect the S2 terminals to the earth.
This connection can be used with distributed and equal loads.
It is possible to measure the current on one phase (using only one
CT). The unmonitored phase currents are mathematically
calculated.
The measurement of neutral current is optional.
WARNING: If the instrument has the TTA on the current inputs,
DON’T connect the S2 terminals to the earth.