HT instruments MACROTEST G3 - Manual (Page 96)

MACROTESTG3 - COMBIG3
EN - 95
Depending on the set values of phase-phase, phase-neutral or phase-PE voltage (see §
5.1.3) 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. 36) depends on:

Protection type (curve)
 Rated current of the protection device
 Time of fault extinction by the protection
Fig. 36: Example of curves relative to magnetothermal (MCB) protection
The instrument allows the selection of the following parameters:

MCB current (B curve) selectable among values:
6, 10, 13, 15, 16, 20, 25, 32, 40, 50, 63A
 MCB current (C, K curves) selectable among values:
0.5, 1, 1.6, 2, 4, 6, 10, 13, 15, 16, 20, 25, 32, 40, 50, 63A
 MCB current (D curve) selectable among values:
 0.5, 1, 1.6, 2, 4, 6, 10, 13, 15, 16, 20, 25, 32A
 Nominal current Fuse gG selectable among values: 2, 4, 6, 8, 10, 12, 13, 16, 20, 25, 32,
40, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630, 800, 1000, 1250A
 Nominal current Fuse aM selectable among values: 2, 4, 6, 8, 10, 12, 16, 20, 25, 32, 40,
50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630A
 Time of fault extinction by the protection selectable among: 0.1s, 0.2s, 0.4s, 5s