Manual

82 Gossen Metrawatt GmbH
19.1 Voltage Drop Measurement (at Z
LN
) – U Function
Significance and Display of U (per IEC 60364-6)
Voltage drop from the intersection of the distribution network and
the consumer system to the point of connection of an electrical
power consumer
(electrical outlet or device connector terminals)
should not exceed 4% of nominal line voltage.
Calculating voltage drop (without offset):
U = Z
L-N
× nominal current of the fuse
Calculating voltage drop (with offset):
U = (Z
L-N
– Z
OFFSET
) × nominal current of the fuse
U in % = 100 × U / U
L-N
See also section 14 regarding the measurement procedure and
connection.
Connection and Test Setup
Set Parameters
Note
If nominal current I
N
is changed by U
OFFSET
, the offset
value is automatically adjusted.
Set Limit Values
TAB Limit value per German technical connection conditions
for connection to low-voltage mains between the distribu-
tion network and the measuring device
DIN Limit value per DIN 18015-1: U < 3%
between the measuring device and the consuming device
VDE Limit value per DIN VDE 0100-520: U < 4%
between the distribution network and the consuming
device (adjustable up to 10% in this case)
NL Limit value per NIV: U < 5%
Measurement Without OFFSET
Proceed as follows:
➭ Switch OFFSET from ON to OFF.
Determine OFFSET (in %).
Proceed as follows:
➭ Switch OFFSET from OFF to ON. U
OFFSET = 0.00% is displayed.
➭ Connect the test probe to the point of common coupling
(measuring device / meter).
➭ Start measurement of offset with I
N
.
First of all, an intermittent acoustic warning is
generated and a blinking message appears, in
order to prevent inadvertent deletion of a pre-
viously saved offset value.
➭ Start offset measurement by pressing
the triggering key once again, or abort
offset measurement by pressing the
ON/START ▼ key (in this case ESC).
U
OFFSET x.xx % is displayed and x.xx can be a value within a
range of 0.00 to 99.9%.
An error message appears in a pop-up window if Z exceeds 9.99 
Start measurement with OFFSET.
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Nominal current: 2 … 160 A
Polarity selection: Lx-N
Diameters: 1.5 … 70 mm
Cable type: NY…, H03… - H07…
Number of wires: 2 … 10-wire
Tripping characteristics: B, L
Limit Value:
U % > Limit Value
U
L
 R
L
U
Red
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