The Ecodesign for Energy-Related Products and Energy Information Regulations 2021

Variable speed drives

3.—(1) For the determination of the IE class, the power losses of VSDs (“VSD losses”) must be determined at 100 per cent rated torque-producing current and 90 per cent rated motor stator frequency.

(2) The VSD losses must be determined according to one of the following methods—

(a) the input minus output method; or

(b) the calorimetric method (calculating power losses by measuring the heat emitted by the VSD).

(3) The test switching frequency must be 4 kilohertz (kHz) when power is at 111 kVA (90 kW) or below, and 2 kHz when power is above111 kVA (90 kW), or at the default factory settings as defined by the manufacturer.

(4) VSD losses may be measured at a frequency of up to 12 Hz instead of zero.

(5) Manufacturers or their authorised representatives may also use the single loss determination method for determining VSD losses.

(6) For the purposes of sub-paragraph (5)—

(a) calculations must be performed with respect to component manufacturer’s data with typical values of power semiconductors at the actual VSD operating temperature or at the maximum operating temperature specified in the datasheet;

(b) where no component manufacturer data is available, losses must be determined by measurement, as follows—

(i) a combination of calculated and measured losses may be used;

(ii) the different individual losses must be calculated or measured separately, and the total losses determined as the sum of all individual losses.