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Current transformer
Current transformers with either 1A or 5A sec-
ondary can be connected to the UMG96L.
A transformer ratio of 5A/5A is preset by the
manufacturer. In programming mode the cur-
rent transformer setting is marked by the sym-
bol „
CT
“.
Programming
In programming mode please scroll to the cur-
rent transformer ratio by pressing key 2. Con-
firm the selection by pressing key 1.
The first digit of the primary current flashes and
can be changed by pressing key 2.
If key 1 pressed again the next digit will be se-
lected and flashes now.
If the entire digit flashes, the decimal point can
be moved.
Press key 2 shortly - The decimal point moves
to the right.
Press key 2 longer - The decimal point moves
to the left.
If no digit flashes anymore, you can shift to the
indication of the voltage transformer.
Primary
(5.00kA = 5000A)
Secondary
Current
transformer
symbol
PRG
k A
L1
L2
L3
CT
Example: Sum current transformer
A current measurement is carried out via two
current transformers, one with a ratio of 1000/
5A and another transformer with a ratio of 200/
5A. The sum measurement is carried out with
a sum current transformer 5+5/5A.
The UMG96L has to be programmed with the
following values:
Primary current: 1000A + 200A =
1200A
Secondary current:
5A
Attention!
The program allows current and voltage
transformer ratio setting only, if the maxi-
mum phase power can reach up to
50.0MW and the sum power can reach a
maximum value of 150.0MW.