IEC 61000-4-29 Edition 2.0: One DC Supply as the Whole Generator

Standards & compliance · 4 min read · 39 cited facts

Edition 2.0 of IEC 61000-4-29 was published on 30 July 2026, replacing the first edition of 2000. That gap has a practical consequence: almost everything a search returns about this standard describes the withdrawn text. A test plan or a vendor page that quotes -4-29 without naming the edition almost certainly predates July 2026, and its generator figures need re-checking before anything gets bought against them.

The standard covers voltage dips, short interruptions and voltage variations on DC input power ports — the DC counterpart of IEC 61000-4-11, with two structural differences. Durations run in absolute seconds rather than mains cycles, and interruptions come in two defined modes, high-impedance and low-impedance, which have no AC equivalent. The AC side has its own article on this site; none of its numbers transfer.

The levels, in seconds

Parameter	Value	Clause
Voltage dip levels	40 % and 70 % of UT (60 % and 30 % dips), abrupt microsecond-range transitions	Clause 5 / Table 1
Short interruptions	0 % UT for 0.001 / 0.003 / 0.01 / 0.03 / 0.1 / 0.3 / 1 s, in high-impedance and/or low-impedance condition	Table 2
Voltage variations	85 % and 120 %, or 80 % and 120 % of UT, for 0.1 / 0.3 / 1 / 3 / 10 s; ramp times set by the product standard	Table 3
Rated-voltage-range rule	if the upper limit of the EUT's rated range exceeds the lower by more than 20 %, the full procedure runs at both limits	Clause 5

Test levels — Edition 2.0

Annex A accepts a single programmable DC supply

This is the commercially interesting part. Annex A, Figure A.2, accepts one programmable DC power supply as the whole generator architecture — no switch network, no dedicated dip generator — provided it meets conditions that each disqualify most bench supplies on their own.

Parameter	Value	Clause
Voltage-change edges	rise and fall 0.5–50 µs into a 100 Ω load, overshoot/undershoot < 10 % of the change	§6.2.1
Peak inrush current drive	50 A at 24 V, 100 A at 48 V, 220 A at 110 V, 100 A at 650 V — positive towards the EUT and negative reverse from it	§6.2.2
Steady-state current margin	generator rated output current at least 120 % of the EUT's rated input current	§6.2.1
Generator output voltage	up to 120 % of the maximum UT; a 780 V DC / 25 A generator is recommended to cover a large number of applications	§6.2.1

What the one-supply architecture must meet

The edge figure and the 780 V / 650 V generator figures come from the Edition 2.0 redline — recent changes, not carried-over 2000 text. The inrush requirement runs both directions: the generator drives the §6.2.2 peak currents positive towards the EUT, and a supply that cannot take the negative reverse current back from the EUT does not qualify, whatever its source rating says.

Interruptions add a condition that a programmed setpoint cannot satisfy: the high-impedance mode requires a genuine disconnection, so the EUT cannot back-feed the gap. A supply regulating its output at zero remains a low-impedance short across the port — that runs the low-impedance case only, and a test plan calling for both modes needs the output to actually open.

Where the scope stops

Ripple on the DC port belongs to IEC 61000-4-17, not to this document.
AC input ports belong to IEC 61000-4-11, where durations run in mains cycles.
Transient overvoltages injected by network faults are explicitly out of scope.
Severity selection and pass/fail criteria are deliberately left to product committees — this standard defines the method; your product standard picks the levels.

Running -4-29 from one supply?

Send the EUT's rated input current and its UT range. The edge rate, the inrush table and the 20 % margin decide whether a single programmable supply can be your generator — we will tell you plainly if it cannot.

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