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GMC-I Messtechnik GmbH
9.1 AC Measurement with (Clip-On) Current Transformers
9.1.1
Transformer Output mA/A
Attention!
If current transformers are used at the secondary
side in an open condition, e.g. due to defective
or non-connected power cables, a blown device
fuse or incorrect connection, dangerously high
voltages can occur at the connections. For this
reason, check to see if the measuring instru-
ment’s current path and transformer’s second-
ary winding, which is connected to the
instrument, complete a closed current circuit,
and connect the transformer to the
and mA or
A jacks.
Some current transformers (e.g. Z3511 ... 3514) include
safety devices, which prevent dangerous voltage increases
at open electrical circuits.
The maximum allowable operating voltage at the primary
conductor is equal to the nominal voltage of the current
transformer. When reading the measurement value, con-
sider the transformation ration of the transformer, as well
as additional display error.
9.1.2
Transformer Output mV/A (e. g. Z201A ... 203A)
Some transformers have a voltage output
(designation: mV/A). Consequently, the secondary con-
nection must be connected to
and V.
mA
600V
A
V
F
600 V CAT II / 300 V CAT III
400mA fused
10A fused
9.1.2
9.1.1
Primary conductor
M
mA
600V
A
V
F
600 V CAT I I / 300 V CAT II I
400mA fused
10A fused
