10
4 Wiring
Diagrams
4.1 Power
Supply
The instrument is fitted with a separated power supply with extended
functioning range. The terminals for the power supply are numbered
(13 and 14). Use cables with max cross-section of 4 mm
2
.
4.2 Measurement Connections
4.2.1 Voltage connection
Use cables with max cross-section of 4 mm
2
and connect them to the terminals marked VOLTAGE INPUT
on the instrument according to the applicable diagrams that follow.
4.2.2 Current connection
It is necessary to use external CTs with a primary rating adequate to the load to be metered and with a 5A
secondary rating. The number of CTs to be used (1, 2 or 3) depends upon the type of network.
Connect the CT output(s) to the terminals marked CURRENT INPUT of the instrument according to the
applicable diagrams that follow.
Use cables with cross-section adequate to the VA rating of the CT and to the distance to be covered. The
max cross-section for the terminals is 4 mm
2
.
N.B. The CT secondary must always be in short circuit when not connected to the instrument in order to
avoid damages and risks for the operator.
Warning: THE PHASE RELATIONSHIP AMONG VOLTAGE AND CURRENT SIGNALS MUST BE
CAREFULLY RESPECTED. ALL DISREGARD OF THIS RULE OR OF THE WIRING DIAGRAM
LEADS TO SEVERE MEASUREMENT ERRORS.
