T1689 Technical Manual Rev 07
Specification
MV3000 Air Cooled DELTA
DELTA Rectifier Module
Page 35
2.9.1.3
External Requirements
•
For parallel operation of rectifier modules, external sharing reactors must be fitted;
•
For 12-pulse operation, the two supplies must be phase shifted by 30° to each other, and be of
balanced voltage. The d.c. output must be through an interbridge transformer;
•
Protection of the main input rectifier devices is by the addition of external semi-conductor fuses.
For recommended fuses, see Section 2.9.1.4 - Current Ratings and Recommended Fuses;
•
The a.c. and d.c. terminals on the modules are not suitable to support the weight of any attached
cables. These cables must have additional mechanical support;
•
These modules must be cooled by an external MVC3014-4001 fan assembly located above the
unit.
2.9.1.4
Current Ratings and Recommended Fuses
Overloads are for 60 seconds, 6 times per hour equally spaced.
All ratings assume standard drive configurations using the recommended interbridge transformers.
Parallel Ratings
Output current should be de-rated by 10% in the following circumstances:
•
Two separate rectifier modules connected in parallel;
•
Two halves of the same rectifier connected in parallel (6 pulse).
In systems with parallel rectifiers, a.c. line reactors will be required.
Fusing
To protect a DELTA rectifier module from d.c. link side short circuits it is recommended that semi-conductor
fuses be fitted in the a.c. supply. The current rating of the rectifier module with the recommended fuses is
given in Table 2–15. Other manufacturers’ fuses may be used but they should be equivalent to the types
specified in this manual. Appendix B: Electrical Connection Diagrams includes details of the input power
circuits and the fusing arrangements.
Module
Voltage (V)
Fuse
DC Current Rating (A)
For 1.5
Overload
For 1.1
Overload
MVR1600-4601
500 - 690
Cooper Bussmann, 170M6718 (3
qty)
1600
Ferraz, 8.5 URD 73 TTF 1400, Ref No.
: S 300 718 (3 qty)
MVR1600-4601
500 - 690
Cooper Bussmann, KTU-1500 (3 qty)
1300
Ferraz, 6.6 URD 33 TTF 1400.
Ref no. C 300 085 (3 qty)
Table 2–15. – Recommended Fuses For Rectifier Module Input Protection
NOTES: Semi-conductor fuses of the correct rating must be fitted to each of the three phases of the a.c. supply input
to protect against catastrophic failure of the input rectifiers.
The fuses should be fitted remotely from the rectifier;
All ratings are calculated assuming a 31 MVA supply (fault level), no added impedance.
The codes for fuses may not specify the mechanical details. These should be selected to suit user
requirements.
All incoming mains cables should be protected with fuses according to local wiring regulations, for example,
in Europe (or any other countries that use IEC standards) using fuses type gG and in USA and Canada using
Class L fuses.
