Chapter 5 - Exchange of Thyristors for Size A5
DCS 500 / DCS 600 Service Manual
VI A
5 - 1
Installation of "Disc
Type" thyristor in con-
verters size A5
(900...2000 A)
All DCS 500 and DCS 600 converters sizes A5/C3/C4 are equipped
with disk type thyristors. The structure of the "Disc type" semicon-
ductor component is such that it requires a certain compression
force to operate. The prevention of overheating of the component
essentially depends on a well heat dissipation between the semi-
conductor and the conducted heat sink. It is thus important that all
joints have good thermal and electrical conduction.
Required Tools
Special tools or material needed in addition to standard tools for the
exchange of thyristor modules:
-
Torque spanner for electrical connections:
13 Nm (M8)
25 Nm (M10)
50 Nm (M12)
-
Screws are metric type; use appropriate nuts.
-
17 mm ring spanner for fuse and busbar connections.
-
17 mm ring spanner for press clamp.
-
Tissue paper / solvent (e.g. ethanol).
-
Thermal joint compound:
type
BECHEM-RHUS SU 2
(grease)
Manufacturer:
Carl Bechem GmbH, 58089 Hagen
ABB Service:
GHSN 390 001 P 0001
-
Disassembly tool
3ADT 621 023 P1
Note:
For more detailed information about the wiring of
the power part, see manual
Technical Data.
Therefore strict observance of the build in instructions given below
is of utmost importance. Make sure that the new component can
replace the old one in accordance with the spare part list (see
Ap-
pendix A).
Semiconductors and heat sinks are to be handled carefully to avoid
scratches and other damage. Avoid touching the contact surfaces.
Do not lift the semiconductor with the gate wire. Do not lift the
semiconductor unit touching the current contact surfaces. Do not
damage the welding flange or the contact surface.
Before you start work, disconnect the converter
completly from the power supply then check the
voltage free condition and make sure, everything
is located in an electrically and mechanically safe
condition!
3ADW000093R0601_DCS500B/DCS600_Service Manual_e_f
