ABB DCS800 Hardware Manual page 95

Measuring board SDCS-PIN-51
This board is always used together with SDCS-PIN-4x board. On this
board there are the circuits located needed for current, voltage and
temperature measuring and for hardware coding.
The current is measured by current transformers at the main AC
inputs, rectified by a diode bridge and scaled with burden resistors.
The nominal current is adjusted by cutting out resistors (R1 ... R21)
from the board according to the current coding table. The resistors
R22 ... R26 are used for the current equal to zero detection. These
resistors must be cut off too, according to the current coding table.
Voltages (U1, V1, W1 and C1(+) and D1(-)) are measured by using
high ohm resistor chains. Scaling of AC and DC voltage is done by
activating 1 MΩ resistors (= cutting out short circuit wires, which are
represented by low ohmic resistors).
Layout of the SDCS-PIN-51 board
W5
R123
V1
W1
C1
D1
Isolating
supports
line potential !
U1
W5 W4 W3 W2
W11 W9 W8 W7 W6
W16 W15 W14 W13
W21 W20 W19 W18 W17
W26 W25 W24 W23
SDCS-PIN-51
3ADW000194R0611 DCS800 Hardware Manual f us
The voltage measurement uses 5 resistor:
U1:W1 to W5
V1:W6 to W11
W1:W12 to W16
C1(+):W17 to W21
D1(-):W22 to W26
If there is a need for voltage adaptation, all 5 chains must be han-
dled in the same way.
Note! Actual voltage signals U1, V1, W1, C1(+) and D1(-) of the
main circuit are not galvanically isolated from the control board.
Because of that a current of less than 1 mA will flow to earth.
When galvanically isolated measurement is needed, please contact
your ABB representative..
PTC
X22 X122
W1
4
3
S3
1 2
W10 W70
W12
W80
W22
305
see diagram
power part
2
X23 X24 2
1 1 1
Two PTC
R1 . . . . . . .
One PTC
W71 W72
X12S X413S
W81 W82
W83
X13S
95
Conductive
supports
X25 2
R21
R22
R26
X313S
S2 S1
Technical data