MI 2087 Instaltest 61557
Measurement instructions
26
3.5. RCD - Contact Voltage and Fault Loop Resistance
For general information concerning Contact Voltage / Fault Loop Resistance
measurement refer to enclosed handbook
Measurements on electric installations
in practice and theory
.
How to carry out the measurement?
Step 1
•
Connect test cable
(Plug commander or Universal test cable) to Instaltest 61557.
•
Set function switch to
Uc, R
L
position, “Contact Voltage initial menu” or “Fault
Loop Resistance initial menu” will be displayed; see the figure below.
Uc
or
looP
is displayed for a while before initial menu appears.
Fig. 20.
Contact Voltage initial menu (left) and Fault Loop Resistance initial menu
Step 2
•
Select required function i.e. Contact Voltage or Fault Loop Resistance by
pressing the SELECT key first. Previously set function (
Uc
or
looP
message)
starts to flash. Select the function by using the
↑↑↑↑
and
↓↓↓↓
keys.
Fault Loop Resistance function takes longer measurement time but offers better
accuracy of Fault Loop Resistance result (in comparison with the R
L
subresult in Uc
function).
Step 3
•
Select Nominal differential current I
∆
n
as follows:
•
Press the
SELECT
key, last set Nominal differential current starts to blink.
•
Select appropriate value by using the
↑↑↑↑
and
↓↓↓↓
keys. The following values are
available to be selected: 10, 30, 100, 300, 500 or 1000 mA.
G
(
G
eneral)
type of RCD
is selected.
S
(
S
elective)
type of RCD
is selected.
