CS 2099 Eurocheck
Eurocheck operation
15
q
Selected I
Δ
n current will affect dissipation of measurement results. Lower I
Δ
n
currents (especially 10 mA) will cause larger variations in results. Consider
accuracy of trip-lock function when evaluating calibration results (accuracy is
defined in User manual of your instrument).
4.7 Line impedance calibration
Line impedance is measured between L and N conductors.
Line impedance calibration can be performed with universal test cable, plug cable or
even plug commander.
Calibration procedure is basically the same as the procedure for fault loop impedance
function (chapter 4.5). Only differences between both procedures are noted below.
Step
Action
1
q
The same as fault loop impedance function.
q
Follow connection diagrams shown in Figure 4.1 and Figure 4.2.
2
q
Switch on the tested instrument and select line impedance function.
3
q
The same as fault loop impedance function.
4
q
The same as fault loop impedance function (line impedance will be
measured instead of loop).
5
q
Perform line impedance measurement with the tested instrument.
q
Write down measurement result for documentation purposes (it will be in
11
Ω
– 12
Ω
range in most cases).
6
q
The same as fault loop impedance function (line impedance will be
measured instead of loop).
7
q
Perform line impedance measurement with the tested instrument.
q
Write down measurement result for documentation purposes (it will be in
1
Ω
– 2
Ω
range in most cases).
8
q
Calculate the difference between LOOP+11
Ω
and LOOP+1
Ω
measurement results – it has to be close to 9.8
Ω
(see Eurocheck
technical specification).
q
If impedance difference deviates significantly from 9.8
Ω
, it is very likely
the tested instrument is damaged. Send it to your distributor or
manufacturer for repair and/or readjustment.