TESTBOY TV 450
Line impedance
45
5.6 Line impedance and prospective short-circuit current
Line impedance is measured in loop comprising of mains voltage source and line wiring.
It is covered by requirements of the EN 61557-3 standard.
See chapter
4.1 Function selection
for instructions on
key functionality.
Figure 5.26: Line impedance
Test parameters for line impedance measurement
FUSE type
Selection of
fuse
type
[---, NV, gG, B, C, K, D]
FUSE I
Rated current
of selected fuse
FUSE T
Maximum
breaking time
of selected fuse
Lim
Minimum short circuit
current
for selected fuse.
See Appendix A for reference fuse data.
Connections for measurement of line impedance
L1
L2
L3
N
PE
R
E
Ro
L
PE
N
L/L
1
N/L2
PE/L3
N/
L
2
L
/L
1
PE
/L
3
Figure 5.27: Phase-neutral or phase-phase line impedance measurement – connection
of plug commander and 3-wire test lead
Line impedance measurement procedure
* model TESTBOY TV 450 (TYPE B)
Select the
Z-LINE
function using the function selector switch.
Select test
parameters
(optional).
Connect
test cable to the instrument.
Connect
test leads to the to the item to be tested (see
figure 5.27
).
Press the
TEST
key to perform the measurement.
Store
the result by pressing the MEM key (optional)*.
