HT COMBI521, Руководство пользователя

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COMBI521
EN - 57
6. Press the
GO/STOP key on the instrument, the START
key on the remote switch probe or use the AutoStart
feature (see § 5.1.5). The instrument starts the
measurement and the “
Measuring… ” message is shown
on the display.
L O O P 15/10 – 18:04
TN
Ipfc
ZL-PE
=
=
- - -
- - -
A

FREQ. = 50.00Hz
VL-PE=231V
VL-N=232V
Measuring…
L-PE STD
FUNC MODE
7. During this whole stage, do not disconnect the measuring
leads of the instrument from the system under test. The
following screen appears on the instrument's display.
The value of the prospective short-circuit current (Ipfc) is
shown in the upper part of the display, while the
Line/Fault loop Z
L-PE
impedance is shown in the bottom
part of the display.
The Standard (Std) prospective short-circuit current (Isc)
is calculated using the following formulas:
Z
MEAS
= measured L-L,L-N,L-PE loop impedance
U
NOM
= nominal voltage (depending on the system)
PE L
NOM
PE SCL
Z
U
I



N L
NOM
N SCL
Z
U
I



L L
NOM
L SCL
Z
U
I



3
R C D 15/10 – 18:04
TN
Ipfc
ZL-PE
=
=
163
1.41
A

FREQ. = 50.00Hz
VL-PE=231V
VL-N=232V
L-PE STD
FUNC MODE
8. Press the SAVE key to store the test result in the instrument’s memory (see § 7.1) or
the ESC/MENU key to exit the screen without saving and go back to the main
measuring screen.