IEC 61326-3-1 EMC test limits for functional safety devices

IEC 61326-3-1:2017 defines dedicated EMC immunity test levels for equipment intended for functional safety applications. Tables 3–7 of the standard specify test values per port type — all of them with performance criterion DS (the device must maintain or reach a detectable, defined state).

The following table consolidates Tables 3–7 into a single overview. The required performance criterion is DS for every test listed.

Phenomenon (basic standard)	AC power ports, input/output	DC power ports, input/output	I/O signal/control ports	I/O signal/control ports connected direct to power supply network	Functional earth port
Burst (IEC 61000-4-4)	SIL 1&2: 3 kV (5/50 ns, 5 kHz) SIL 3: same level, test duration at highest level ×5	SIL 1&2: 3 kV (5/50 ns, 5 kHz) SIL 3: same level, test duration at highest level ×5	SIL 1&2: 2 kV (5/50 ns, 5 kHz) SIL 3: same level, test duration at highest level ×5 only for lines longer than 3 m	SIL 1&2: 3 kV (5/50 ns, 5 kHz) SIL 3: same level, test duration at highest level ×5	SIL 1&2: 2 kV (5/50 ns, 5 kHz) SIL 3: same level, test duration at highest level ×5
Surge (IEC 61000-4-5)	SIL 1&2: 2 kV line-to-line, 4 kV line-to-ground SIL 3: same levels, number of pulses at highest level ×3 level may be achieved via external protection devices (specify devices and installation requirements in user documentation)	SIL 1&2: 1 kV line-to-line, 2 kV line-to-ground SIL 3: same levels, number of pulses at highest level ×3 level may be achieved via external protection devices (specify devices and installation requirements in user documentation)	SIL 1&2: 2 kV line-to-ground SIL 3: same level, number of pulses at highest level ×3 only for long-distance lines (IEC 61326-1:2012 §3.10); level may be achieved via external protection devices (specify in user documentation)	SIL 1&2: 2 kV line-to-line, 4 kV line-to-ground SIL 3: same levels, number of pulses at highest level ×3 use the coupling network for AC/DC power lines; level may be achieved via external protection devices (specify in user documentation)	—
Conducted RF (IEC 61000-4-6)	10 V (150 kHz–80 MHz, 1 kHz, 80 % AM) applied in the frequency ranges of IEC 61326-3-1 Table 9; ISM frequencies are taken into account individually	10 V (150 kHz–80 MHz, 1 kHz, 80 % AM) applied in the frequency ranges of IEC 61326-3-1 Table 9; ISM frequencies are taken into account individually	10 V (150 kHz–80 MHz, 1 kHz, 80 % AM) applied in the frequency ranges of IEC 61326-3-1 Table 9; ISM frequencies are taken into account individually	10 V (150 kHz–80 MHz, 1 kHz, 80 % AM) applied in the frequency ranges of IEC 61326-3-1 Table 9; ISM frequencies are taken into account individually	—
Conducted common-mode voltage (IEC 61000-4-16)	1 V→10 V, 20 dB/decade (1.5–15 kHz) 10 V (15–150 kHz)	1 V→10 V, 20 dB/decade (1.5–15 kHz) 10 V (15–150 kHz) 10 V (DC, 16⅔ Hz, 50/60 Hz, 150/180 Hz) 100 V short duration, 1 s (DC, 16⅔ Hz, 50/60 Hz)	1 V→10 V, 20 dB/decade (1.5–15 kHz) 10 V (15–150 kHz) 10 V (DC, 16⅔ Hz, 50/60 Hz, 150/180 Hz) 100 V short duration, 1 s (DC, 16⅔ Hz, 50/60 Hz) only for long-distance lines (IEC 61326-1:2012 §3.10) and only for earthed systems/equipment	1 V→10 V, 20 dB/decade (1.5–15 kHz) 10 V (15–150 kHz) 10 V (DC, 16⅔ Hz, 50/60 Hz, 150/180 Hz) 100 V short duration, 1 s (DC, 16⅔ Hz, 50/60 Hz)	—
Voltage dips	0 % for 1 cycle 40 % for 10 cycles (50 Hz) / 12 cycles (60 Hz) 70 % for 25 cycles (50 Hz) / 30 cycles (60 Hz) (IEC 61000-4-11 or IEC 61000-4-34)	40 % U_T for 10 ms (IEC 61000-4-29)	—	—	—
Short interruptions	0 % for 250 cycles (50 Hz) / 300 cycles (60 Hz) (IEC 61000-4-11 or IEC 61000-4-34)	0 % U_T for 20 ms (IEC 61000-4-29)	—	—	—

Notes

All values in the table apply to functions intended for safety applications. Non-safety functions may be disturbed — see performance criterion DS.
DC connections between parts of equipment that are not connected to a DC distribution network are treated as I/O signal/control ports, not as DC power ports.
Dash (—) means the standard defines no test of that phenomenon for that port type.