Accessories
4.8 Residual current devices
3VA molded case circuit breakers with IEC certificate
434
Manual, 03/2019, A5E03603177010-03
Parameterization of the residual current device
①
Button for setting tripping characteristic type B / type B+
②
Setting button for response current I
Δn
③
Setting button for delay time Δt
Button for setting the tripping characteristic
This rotary switch can be used to change the tripping characteristic of the RCD520B
between type B (according to IEC 62423 and IEC 60947-2) and type B+ (according to
DIN VDE 0664-400 for I
Δn
= 30 to 300 mA and for frequencies over 1 kHz).
The same conditions apply for type B+ as for type B, i.e. the tripping characteristics of type B
and type B+ are identical up to 1 kHz. With device type B+ however, the frequency range for
the detection of residual currents extends up to 20 kHz. Tripping takes place below 420 mA
within this frequency range to provide increased fire protection. With type B, the tripping
threshold increases above 1 kHz to prevent spurious tripping due to discharge currents,
particularly in conjunction with frequency converters.