Evaluation Of Measured Values; Measuring Line Impedance (Z L-N Function) - Gossen MetraWatt PROFITEST MBASE MTECH Operating Instructions Manual

8.2

Evaluation of Measured Values

The maximum allowable loop impedance Z
played after allowance has been made for maximum operating
measurement error (under normal measuring conditions) can be
determined with the help of Table 1 on page 57. Intermediate val-
ues can be interpolated.
The maximum allowable nominal current for the protective device
(fuse or circuit breaker) for a nominal line voltage of 230 V, after
allowance has been made for the maximum measuring error of
the device, can be determined with the help of Table 6 on page
58 based upon measured short-circuit current (corresponds to
DIN VDE 0100, part 600).
Special Case Suppression of Limit Value
The limit value cannot be determined. The test person is
requested to evaluate the measured values himself and to
acknowledge or reject them via softkeys.
Measurement passed: Key
Measurement failed: Key X
The measured value cannot be stored until it has been evaluated
by the test person.
GMC-I Messtechnik GmbH
which may be dis-
L-PE
4
9 Measuring Line Impedance (Z
Measuring Method (internal line resistance measurement)
Supply impedance Z is measured by means of the same
L-N
method used for loop impedance Z
23). However, the current loop is completed via neutral conductor
N rather than protective conductor PE, as is the case with loop
impedance measurement.
Select the Measuring Function
Z
L-N
Connection, TT System
Connection, TN-S Sys-
tem
Set Parameters
Nominal current: 2 ... 160 A
Tripping characteristics: B/E,C,D,K
Cross-section*: 1.5 ... 70 sq. mm
Cable types*: NY..., H03... - H07...
Number of wires*: 2 ... 10-strand
Country-specific Plug Insert, e.g. SCHUKO
2-Pole Adapter
function)
L-N
(see section 8 on page
L-PE
25