Ecodesign Tier 2 explained: the loss limits every EU transformer must meet

"Tier 2" appears on every PNACHO data sheet. It is not a marketing badge – it is the second, stricter stage of the EU Ecodesign regulation for power transformers, mandatory for every unit placed on the EU market since 1 July 2021. This article explains what the regulation requires and how to read the numbers.

What the regulation covers

Commission Regulation (EU) 2019/1783 (which replaced 548/2014) applies to power transformers with a minimum rating of 1 kVA used in 50 Hz transmission and distribution networks. For distribution transformers up to 3 150 kVA it sets maximum no-load losses (P0) and maximum load losses (Pk). Tier 1 applied from 2015; Tier 2 tightened the limits from July 2021. A transformer that exceeds either limit cannot be CE-marked and cannot legally be installed in the EU.

Tier 2 limits – oil-immersed, Um ≤ 24 kV

Rated power	Max. load losses Pk	Max. no-load losses P0
25 kVA	600 W	63 W
50 kVA	750 W	81 W
100 kVA	1 250 W	130 W
160 kVA	1 750 W	189 W
250 kVA	2 350 W	270 W
400 kVA	3 250 W	387 W
630 kVA	4 600 W	540 W
800 kVA	6 000 W	585 W
1 000 kVA	7 600 W	693 W
1 250 kVA	9 500 W	855 W
1 600 kVA	12 000 W	1 080 W
2 000 kVA	15 000 W	1 305 W
2 500 kVA	18 500 W	1 575 W

Ratings between the table values (for example 40 or 63 kVA) are interpolated linearly, as the regulation allows.

Tier 2 limits – dry-type (cast resin), Um ≤ 24 kV

Rated power	Max. load losses Pk	Max. no-load losses P0
100 kVA	1 800 W	252 W
160 kVA	2 600 W	360 W
250 kVA	3 400 W	468 W
400 kVA	4 500 W	675 W
630 kVA	7 100 W	990 W
800 kVA	8 000 W	1 170 W
1 000 kVA	9 000 W	1 395 W
1 250 kVA	11 000 W	1 620 W
1 600 kVA	13 000 W	1 980 W
2 000 kVA	16 000 W	2 340 W
2 500 kVA	19 000 W	2 790 W

Why no-load losses matter more than they look

Load losses scale with the square of the load; no-load losses are constant from the moment the transformer is energised. A 630 kVA oil unit at the Tier 2 limit burns 540 W × 8 760 h = 4 730 kWh a year even if nothing is connected. At 0.15 €/kWh that is about 700 € per year, 21 000 € over 30 years – more than the purchase price. This is why the regulation cut no-load limits by 10 % between Tier 1 and Tier 2 and why the value is printed on every PNACHO product page.

What to ask for in a tender

• Guaranteed P0 and Pk at rated voltage and 75 °C, with tolerances per IEC 60076-1.
• The EU declaration of conformity referencing Regulation (EU) 2019/1783.
• The routine test report of the delivered unit, not a type-test report of a "similar" unit.

Every PNACHO-O and PNACHO-D transformer is specified to these limits and ships with all three documents.