WEG UR11 Series, Руководство пользователя

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Installation and Connection
3
3-8 | UR11
R1
F1
Q1
F4 F2 F5 F3 F6
R2 S1 S2 T1 T2
L1
900 A 900 A
L2
R S T
UR111140T4SZ
+UD -UD
Figure 3.8 - Example of 6 pulse configuration with one rectifier unit
The Table 3.4 on page 3-8 presents WEG values according to the configuration presented at Figure 3.8 on
page 3-8 (6 fuses per UR11).
Table 3.4 - Recommended Fuses
Nominal
Voltage [V]
ND Current [A] Fuse [A]
Maximum Fuse I
2
t
@ 25 ºC [A
2
s]
380 / 480 1140 900 1.445.000
500 / 600 893 700 1.445.000
660 / 690 811 1.445.000
The fuses must be sized according to the voltage supply of the rectifier in order it can be capable of providing
the arc extinction and the I
2
t must be smaller than the I
2
t of each thyristor (1.445.000 A
2
s), as indicated at Table
3.4 on page 3-8 .
Example of fuses used by WEG:
400 V line: 6,9URD33TTF0900 (FERRAZ, 900 A / 690 V / I²t = 700.000 A²s).
Other lines: 6,9URD33TTF0700 (FERRAZ, 700 A / 690 V / I²t = 300.000 A²s).