CS 2099 Eurocheck
Eurocheck operation
17
4.9 RCD measuring current I
Δ
n=30 mA verification
This test is part of RCD trip-out time calibration and couldn’t be performed separately –
it is valid only for I
Δ
n = 30 mA. Refer to chapter 4.8 for more information.
It is essential that the test instrument measuring current is within certain limits. For
example, standard EN 61557 defines low limit as I
Δ
n – 0 %, and high limit as I
Δ
n + 20
%. Metrel test instruments has even narrower specification, high limit is defined as
I
Δ
n + 10 %.
When RCD trip-out time measurement is performed Eurocheck automatically indicates if
test current was too low or too high (LEDs CURRENT LO or CURRENT HI light
respectively). Eurocheck low limit indication is set to 28 mA, and high limit to 35 mA.
4.10 Insulation resistance calibration
Eurocheck offers 2 insulation resistance values for calibration: 2 M
Ω
and 50 M
Ω
. It is
always possible (and recommended) to add third value into your calibration procedure –
0
Ω
(short-circuited test leads).
It is necessary to calibrate insulation resistance function with all available measuring
voltages. If measuring voltage is set continuously, it is recommended to perform
calibration with the following voltages: 50 V, 100 V, 250 V, 500 V and 1000 V.
Fault loop impedance calibration can be performed with universal test cable or tip
commander. Make sure to follow connection instructions for the tested instrument
(determine the leads of the test cable which are used for this measurement). Generic
connection diagram is shown in Figure 4.3.
Figure 4.3: Performing insulation resistance calibration using universal test cable
PE
N
L