ABB DCS800, Installation And Start-Up Manual

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Hardware
3ADW000197R0101 DCS800-R Sel e a
Interface board SDCS-REB-3
This board is not included in the standard kit. In case the function described later
on gives some advantage it needs to be ordered separately!
In a single thyristor bridge the distance between the 6 thyristors and the pulse
transformer board is often quite short. The length of these cables, which is limited
to 1 meter, is sufficiently long. In big thyristor stages with parallel thyristors the dis-
tance can be longer than 1 meter.
In addition to that, there is another reason, which becomes more critical at big thy-
ristor stages. The wiring of the SDCS-PIN-51, SDCS-REB1 and SDCS-REB-2 is
designed, that firing pulses for one complete thyristor bridge will be available at
SDCS-PIN-48.
To get flexible routing of the firing pulses, the SDCS-REB-3 board comes into use.
This board enables the firing pulses to be assigned to the pulse transformers and
therefore to the thyristors as well.
If the SDCS-REB-3 board is used, it must be installed between the SDCS-REB-2
and the pulse transformer board SDCS-PIN-48. This board represents a matrix
which is used for assigning the current direction signals and the firing pulses re-
ceived at plugs X11: to X:42 to the output plugs X113: to X813:. If possible try to
avoid connecting thyristors of different bridges to the same SDCS-PIN-48. Com-
missioning and testing will become easier.
At a power part with parallel thyristors each thyristor gets a three digit number.
Every digit has the meaning (see chapter
Interfacing the Electronics and Thyristors
figure Arrangement of thyristors in an anti parallel bridge ):
-
thyristors named 1xx, 2xx, 3xx or 4xx belong to the first, second, third or fourth
bridge
-
thyristors named x1x belong to the forward bridge, which is activated by the
current direction signals SR_1ACE and SR_1BDF
-
thyristors named x2x belong to the reverse bridge, which is activated by the
current direction signals SR_2ACE and SR_2BDF
-
thyristors named xx1, xx2, up to xx6 indicate the normal firing sequence by
their number
Firing pulses
The pulse transformer board SDCS-PIN-48 contains 6 channels numbered A to F.
These are in turn subdivided into 2 groups, one with the channels A, C, E and one
with the channels B, D, F. These are controlled by two current direction signals.
The next figure shows the routing of the firing pulses and the activation of the two
groups for three different configurations, used with the bigger standard DCS800-
S0x modules.
Signal flow and Thyristor designation
Signal flow of firing pulses and doubling of current direction signals are shown
based on the relevant figures in chapter
Interfacing the Electronics and Thyristors .
That results in the thristor designation.