Siemens SENTRON - 4 Residual Current Protective Devices; Types of Residual Current Protective Devices

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Residual current protective devices
4. Residual current protective devices
4.1 Types of residual current protective devices
Residual current protective devices are distinguished from one another in respect
of their suitability for detecting different forms of residual current (table 1).
Residual current with different waveforms can occur depending on the electronic
switching in the circuit. Since residual current protective devices differ in their
suitability for detecting residual current waveforms, the relevant load input circuit
must be taken into account when such a device is chosen.
Table 2 shows electronic circuits and their possible load and residual currents,
along with the suitable types of residual current protective device in each case.
According to the function of RCCBs in various types
Current
type
Type AC Type A Type F Type B
Type B+
Tripping
current
0.5 – 1.0 I
Δn
0.35 – 1.4 I
Δn
Lead angle
135°
0.11 – 1.4 I
Δn
max. 1,4 I
Δn
+ 6 mA (Type A)
+ 10 mA (Type F)
+ 0,4 I
Δn
(Type B/B+)
0.5 – 1.4 I
Δn
0.5 – 2.0 I
Δn
~
Table 1: Classication of residual current protective devices into different
types with tripping ranges