Gx
Series
EN - 151
CAUTION
The instrument must be used to measure fault loop impedance values at
least 10 times higher than the resolution value of the instrument in order to
minimize errors.
Depending on the set values of nominal 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 depends on:
Protection type (curve)
Rated current of the protection device
Time of fault extinction by the 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:
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