Tettex 2293 - Power Supply Modes; Parallel Mode on HV-Side 16 A ¦ 100 V (A1) or 32 A ¦ 50 V (A2)

Theory
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3.2 Power Supply Modes
The 3 programmable power supplies in the 2293 can operate in different configurations. These
configurations will be explained in this chapter.
3.2.1 Parallel Mode on HV-side 16A ¦ 100V (A1) or 32A ¦ 50V (A2)
This supply mode is selected, when a phase on the high voltage side of the transformer has to
be measured without the corresponding phase on the low voltage side. The three supplies are
connected in parallel and the range is selected according to the desired measuring current as
follows:
I ≤ 16.0A  16A ¦ 100V
I > 16.0A  32A ¦ 50V
The measuring circuit for phase A of an YNyn0 transformer is illustrated below:
U
1
U
1
N
A
B
C
1
I
32A / 50V
or
16A / 100V
n
a
b
c
The measured resistance is calculated as follows:
1
1
I
U
RRR
NAAN

The following diagram shows the operating area for the power supply in mode A1 and B1 - 16A ¦
100V: