
Gx
Series
EN - 146
Depending on the set values of phase-phase, phase-neutral or phase-PE voltage (see §
5.1.4) and the measured value of fault loop impedance, the instrument calculates the
minimum value
of the assumed short-circuit current to be interrupted by the protection
device. For proper coordination, this value MUST always be greater than or equal to the
Ia
value of the tripping current of the type of protection considered.
The
Ia
reference value (see Fig. 46) depends on:
Protection type (curve)
Rated current of the protection device
Time of fault extinction by the protection
Fig. 46: Example of curves relative to magnetothermal (MCB) protection
The instrument allows the selection (*) of the following parameters:
MCB current (B curve) selectable among values:
3,6,10,13,15,16,20,25,32,40,45,50,63,80,100,125,160,200A
MCB current (C, K, D curves) selectable among values:
0.5,1,1.6,2,3,4,6,10,13,15,16,20,25,32,40,50,63, 80,100,125,160,200A
Nominal current Fuse BS88-2 selectable among values:
2
,
4
,
6, 10, 16, 20, 25, 32, 40,
50, 63, 80, 100, 125, 160, 200A
Nominal current Fuse BS88-3 selectable among values:
5,16,20,32,45,63,80,100A
Nominal current Fuse BS3036 selectable among values:
5,15,20,30,45,60,100A
Nominal current Fuse BS1362 selectable among values:
3,15A
Time of fault extinction by the protection selectable among:
0.1s, 0.2s, 0.4s, 1s, 5s
(*) The values could be subject to variations