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3-13
IM 760401-01E
Before Starting Measurements
3
3.8
Using an External PT or CT to Wire the Circuit
under Measurement
WARNING
When using an external CT, do not allow the secondary side of the CT to become an
open circuit while current is flowing through the primary side. Otherwise, high
voltage will appear at the secondary side of the CT, making it extremely dangerous.
CAUTION
The measurement current flows through the thick lines in the figure below. Use
wires with sufficient current capacity.
Use of a PT (or CT) enables measurement of voltage or current even if the maximum
voltage or maximum current of the object to be measured exceeds the maximum
measuring range.
• If the maximum voltage exceeds 600 V (300 V if the crest factor is set to 6),
connect an external potential transformer (PT), and connect the secondary side of
the PT to the voltage input terminals.
• If the maximum current exceeds 20 A (10 A if the crest factor is set to 6), connect
an external current transformer (CT), and connect the secondary side of the CT to
the current input terminals.
Wiring example of a single-phase, two-wire system (1P2W) when using a PT/CT... Can
be applied to models 760401, 760502, and 760503.
Source
Load
L CT
PT
V
v
Source
Load
L CT
PT
V
v
l
Input terminal
(Elemnt)
l
Input terminal
(Element)
C
±
±
V
C
±
±
V
Wiring example of a single-phase, three-wire system (1P3W) when using a PT/CT...
Can be applied to models 760502, and 760503.
Source
L
l
CT
PT
V
v
load
L
l
CT
PT
V
v
N
Input terminal
(Element 1)
Input terminal
(Element 3)
C
±
±
V
C
±
±
V
Содержание WT210
Страница 1: ...Digital Power Meter IM 760401 01E 3rd Edition ...
Страница 208: ...13 18 IM 760401 01E 13 3 Sample Program Image ...
Страница 214: ...13 24 IM 760401 01E 13 5 Sample Program Output of Normal Measurement Data ...
Страница 266: ...14 50 IM 760401 01E 14 6 Sample Program Image ...
Страница 272: ...14 56 IM 760401 01E 14 8 Sample Program Output of Normal Measurement Data ...