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IEC 61000-3-2:2014 © IEC 2014 – 13 –
– television receivers;
– refrigerators and freezers having one or more variable-speed drives to control compressor
motor(s).
NOTE 2 Class D limits are reserved for equipment that, by virtue of the factors listed in note 1, can be shown to
have a pronounced effect on the public electricity supply system.
6 General requirements
The following restrictions apply even to equipment to which no harmonic current limits apply as
defined in Clause 7.
The requirements and limits specified in this clause are applicable to the power input terminals
of equipment intended to be connected to 220/380 V, 230/400 V and 240/415 V systems
operating at 50 Hz or 60 Hz. Requirements and limits for other cases are not yet considered.
A simplified test method is permitted for equipment that undergoes minor changes or updates,
provided that, in previous full compliance tests, it has been shown to have current emissions
below 60 % of the applicable limits and the THD of the supply current is less than 15 %. The
simplified test method consists of verifying that the updated equipment has an active input
power within ±20 % of that of the originally tested product, and that the THD of the supply
current is less than 15 %. Products that fulfill these requirements are deemed to comply with
the applicable limits, but in case of doubt the result of a full compliance test according to
Clauses 6 and 7 takes precedence over this simplified method.
6.1 Control methods
Asymmetrical controls according to IEC 60050-161, 161-07-12 and half-wave rectification
directly on the mains supply may only be used in the following circumstances:
a) where they are the only practical solution permitting the detection of unsafe conditions, or
b) where the controlled active input power is less than or equal to 100 W, or
c) where the controlled appliance is a portable equipment fitted with a two-core flexible cord
and is intended for use for a short period of time, i.e. for a few minutes only.
If one of these three conditions is fulfilled, half-wave rectification may be used for any purpose,
whereas asymmetrical controls may only be used for the control of motors.
NOTE 1 Such equipment includes, but is not limited to, hair dryers, electrical kitchen appliances and portable
tools.
Symmetrical control methods which are prone to produce harmonics of low order (n ≤ 40) in the
input current may be used for the control of the power supplied to heating elements provided
that the full sine-wave input power is less than or equal to 200 W, or that the limits of Table 3
are not exceeded.
Such symmetrical control methods are also allowed for professional equipment provided that
either
a) one of the above conditions is fulfilled, or
b) the relevant limits are not exceeded when tested at the supply input terminals and in
addition both the following conditions are fulfilled:
1) it is necessary to control precisely the temperature of a heater whose thermal time
constant is less than 2 s, and
2) there is no other technique economically available.
Professional equipment whose primary purpose, considered as a whole, is not for heating, shall
be tested against the relevant limits.
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