Chapter A General rules of electrical installation design

F40
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F - Protection against electric shock
8 Residual current devices (RCDs)
Immunity level for Merlin Gerin residual current devices
The Merlin Gerin range comprises various types of RCDs allowing earth leakage
protection to be adapted to each application. The table below indicates the choices to
be made according to the type of probable disturbances at the point of installation.
Device type Nuisance
trippings
High
frequency
leakage
current
AC b
Schneider Electric - Electrical installation guide 2008
Non-trippings
Fault current Low
Rectified
alternating
Pure direct
temperatures
(down to
- 25 °C)
A b b b
SI b b b b b
Corrosion
Dust
SiE b b b b b b
B b b b b b b
Fig. F71 : Immunity level of Merlin Gerin RCDs
Immunity to nuisance tripping
Type Si/SiE RCDs have been designed to avoid nuisance tripping or non-tripping in
case of polluted network , lightning effect, high frequency currents, RF waves, etc.
Figure F72 below indicates the levels of tests undergone by this type of RCDs.
Disturbance type Rated test wave Immunity
Continuous disturbances
Multi9 :
ID-RCCB, DPN Vigi, Vigi C60, Vigi
C120, Vigi NG125
SI / SiE type
Harmonics 1 kHz Earth leakage current = 8 x I∆n
Transient disturbances
Lightning induced overvoltage 1.2 / 50 μs pulse
(IEC/EN 61000-4-5)
Lightning induced current 8 / 20 μs pulse
(IEC/EN 61008)
Switching transient, indirect
lightning currents
Downstream surge arrester
operation, capacitance loading
Electromagnetic compatibility
Inductive load switchings
fluorescent lights, motors, etc.)
Fluorescent lights, thyristor
controlled circuits, etc.
RF waves (TV&
radio, broadcact,
telecommunications,etc.)
0.5 μs / 100 kHz
“ ring wave ”
(IEC/EN 61008)
4.5 kV between conductors 5.5 kV /
earth
5 kA peak
400 A peak
10 ms pulse 500 A
Repeated bursts
(IEC 61000-4-4)
RF conducted
waves
(IEC 61000-4-6)
RF radiated waves
80 MHz to 1 GHz
(IEC 61000-4-3)
4 kV / 400 kHz
66 mA (15 kHz to 150 kHz)
30 V (150 kHz to 230 MHz)
30 V / m
Fig. F72 : Immunity to nuisance tripping tests undergone by Merlin Gerin RCDs