MI 3101 EurotestAT: Appendix E
Reduced low voltage supply systems
117
E.4.3 Line impedance and prospective short-circuit current
Z
Line-Line
Measuring range according to EN61557 is 0.25
19.9 k
.
Measuring range (
) Resolution
(
)
Accuracy
0.00
9.99
0.01
10.0
99.9
0.1
100
999
1
1.00k
9.99k
10
10.0k
19.9k
100
(5 % of r 5 digits)
Prospective short-circuit current
Measuring range according to EN61557 is 0.25 A
440A (ksc = 1)
Measuring range (A)
Resolution (A)
Accuracy
0.00
0.99
0.01
1.0
99.9
0.1
100
999
1
1.00k
99.99k
10
100k
199k
1000
Consider accuracy of line
impedance measurement
*The accuracy is valid if:
Mains voltage is stable during the measurement
IPSC calculation: .......................................IPSC = U
N
ksc / ZLine-Line
U
N
= 110 V; (90 V
Uinp
121 V)
Maximum loading.......................................3.1 A / 10 ms
Nominal input voltage ................................110 V, 14 Hz
500 Hz
R, XL values are indicative.
