IG-183-EN version 06; 31/03/2020
63
General instructions
cgm
.3 system: medium voltage SF
6
gas-insulated
cubicles up to 38 kV according to IEEE and CSA standards
Recommended sequence of operations
5.8.1. Selection of recommended fuses
The fuses recommended for use in the fuse protection
functional unit are defined according to tests carried
out by the manufacturers. The following table shows the
recommended fuse ratings according to the Ur/Ptransf.
ratio:
U
r
Line
[kV]
U
r
Fuse
[kV]
Rated transformer power WITHOUT OVERLOAD
[kVA]
25 50 75 100 125 160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500
7.2
6/12
6.3
16
16
20
20
25
40
40
50
63
80
100
100
125
160
-
-
-
12.5 10/24
6.3
6.3
16
16
16
20
20
25
31.5
40
50
63
80
80
100
-
-
-
13.2 10/24
6.3
6.3
10
16
16
20
20
25
31.5
40
50
63
63
80
100
-
-
-
14.4 10/24
6.3
6.3
10
16
16
16
20
20
25
40
40
50
63
80
80
-
-
-
25
10/24
6.3
6.3
6.3
6.3
10
16
16
16
20
20
25
31.5
40
50
50
63
80
-
34.5 20/36
-
-
-
6.3
6.3
10
10
16
16
20
20
31.5
31.5
40
40
50
63
80*
General operating conditions:
Without overload and temperature < 104 °F (40 °C).
Recommended fuses:
SIBA brand, type HH, with medium type striker, conforming to IEC 60282-1 (low loss fuses).
The values marked with an (*) correspond to SSK-type fuses.
Maximum permitted power loss for a fuse: < 75 W.
The fuse-switch assembly has been temperature-rise tested under normal service conditions according to IEC 62271-105. A fuse-holder carriage adapted
for 292 mm - 6/12 kV fuses is available.
The measurement of 20/36 kV fuses is 537 mm and the measurement of 10/24 kV fuses is 442 mm. A fuse-holder carriage adapted for 292 mm - 6/12 kV
fuses is available.
If any of the fuses blows, we recommend changing all three.
For overload conditions in the transformer or use of other brands of fuse, please consult
Ormazabal
.
Table 5.10.
Rated transformer power WITHOUT OVERLOAD
