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Exchange of Thyristors for Size D7
3ADW000195R0501 DCS800 Service Manual e e
Exchange of Thyristors for Size D7
Installation of "Disc Type" thyristor in converters size D7 (2050...5200 A)
All DCS800 converters sizes D5/D6/D7 are equipped with disk type thyristors. The
structure of the "Disc type" semiconductor component is such that it requires a
certain compression force to operate. The prevention of overheating of the
component essentially depends on a good heat dissipation between the
semiconductor 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:
Torx
screwdrivers:
TX10,
TX20,
TX25
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.
24 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:
DCF 1066721 P1
Note:
For more detailed information about the wiring of the power part, see Hardware
Manual.
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 Appendix A
).
All thyristors are always mounted in the same direction, independent of current,
voltage, number of quadrants (2-Q or 4-Q), left or right side connection.
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 by touching the current contact
surfaces. Do not damage the welding flange or the contact surface.
Before you start work, disconnect the converter completely from the power
supply then check the voltage free condition and make sure, everything is
located in an electrically and mechanically safe condition!
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]
