MI 3152(H)
Eurotest
XC (2,5 kV)
Tests and measurements
98
Measurement procedure
Enter the
Z loop m
function.
Set test parameters / limits.
Connect test leads to A 1143
– Euro Z 290 A adapter and switch it on.
Connect A 1143
– Euro Z 290 A adapter to the instrument using RS232-PS/2 cable.
Connect test leads to the object under test, see
Figure 7.35
and
Figure 7.36
.
Start the measurement using
or
button.
Save results (optional).
Figure 7.37: Examples of high precision Loop impedance measurement result
Measurement results / sub-results
Z
Loop impedance
Ipsc
Standard prospective fault current
Imax
Maximal prospective fault current
Imin
Minimal prospective fault current
Ub
Contact voltage at maximal prospective fault current (contact voltage measured against
Probe S if used)
R
Resistance of loop impedance
XL
Reactance of loop impedance
Ulpe
Voltage L-PE
Freq
Frequency
Standard prospective fault current I
PSC
is calculated as follows:
𝐼
𝑃𝑆𝐶
=
230 𝑉
𝑍
where
𝑈
𝐿−𝑃𝐸
= 230 𝑉 ± 10 %
The prospective fault currents I
Min
and I
Max
are calculated as follows:
𝐼
𝑀𝑖𝑛
=
𝐶
𝑚𝑖𝑛
𝑈
𝑁(𝐿−𝑃𝐸)
𝑍
(𝐿−𝑃𝐸)ℎ𝑜𝑡
where
𝑍
(𝐿−𝑃𝐸)ℎ𝑜𝑡
= √(1.5𝑅
𝐿−𝑃𝐸
)
2
+ 𝑋
𝐿−𝑃𝐸
2
𝐶
𝑚𝑖𝑛
= {
0.95; 𝑈
𝑁(𝐿−𝑃𝐸)
= 230 𝑉 ± 10 %
1.00; 𝑜𝑡ℎ𝑒𝑟𝑤𝑖𝑠𝑒
and
𝐼
𝑀𝑎𝑥
=
𝐶
𝑚𝑎𝑥
𝑈
𝑁(𝐿−𝑃𝐸)
𝑍
𝐿−𝑃𝐸
where
𝑍
𝐿−𝑃𝐸
= √𝑅
𝐿−𝑃𝐸
2
+ 𝑋
𝐿−𝑃𝐸
2
𝐶
𝑚𝑎𝑥
= {
1.05; 𝑈
𝑁(𝐿−𝑃𝐸)
= 230 𝑉 ± 10 %
1.10; 𝑜𝑡ℎ𝑒𝑟𝑤𝑖𝑠𝑒
Refer to
A 1143
– Euro Z 290 A adapter Instruction manual
for detailed information.
