# Commission Regulation (EU) No 548/2014 of 21 May 2014 on implementing Directive 2009/125/EC of the European Parliament and of the Council with regard to small, medium and large power transformers, Division 1.1: Requirements for three-phase medium power transformers with rated power ≤ 3 150 kVA

Extent: E+W+S+N.I.

Table I.1: Maximum load and no-load losses (in W) for three-phase liquid-immersed medium power transformers with one winding with U m ≤ 24kV and the other with U m ≤ 3,6 kV
Maximum losses for kVA ratings that fall in between the ratings given in Table I.1 shall be obtained by linear interpolation.
Tier 1 (from 1 July 2015)
Tier 2 (from 1 July 2021)
Rated Power (kVA)
Maximum load losses Pk (W)
Maximum no-load losses Po (W)
Maximum load losses Pk (W)
Maximum no-load losses Po (W)
≤ 25
Ck (900)
Ao (70)
Ak (600)
Ao – 10 % (63)
50
Ck (1 100)
Ao (90)
Ak (750)
Ao – 10 % (81)
100
Ck (1 750)
Ao (145)
Ak (1 250)
Ao – 10 % (130)
160
Ck (2 350)
Ao (210)
Ak (1 750)
Ao – 10 % (189)
250
Ck (3 250)
Ao (300)
Ak (2 350)
Ao – 10 % (270)
315
Ck (3 900)
Ao (360)
Ak (2 800)
Ao – 10 % (324)
400
Ck (4 600)
Ao (430)
Ak (3 250)
Ao – 10 % (387)
500
Ck (5 500)
Ao (510)
Ak (3 900)
Ao – 10 % (459)
630
Ck (6 500)
Ao (600)
Ak (4 600)
Ao – 10 % (540)
800
Ck (8 400)
Ao (650)
Ak (6 000)
Ao – 10 % (585)
1 000
Ck (10 500)
Ao (770)
Ak (7 600)
Ao – 10 % (693)
1 250
Bk (11 000)
Ao (950)
Ak (9 500)
Ao – 10 % (855)
1 600
Bk (14 000)
Ao (1 200)
Ak (12 000)
Ao – 10 % (1 080)
2 000
Bk (18 000)
Ao (1 450)
Ak (15 000)
Ao – 10 % (1 305)
2 500
Bk (22 000)
Ao (1 750)
Ak (18 500)
Ao – 10 % (1 575)
3 150
Bk (27 500)
Ao (2 200)
Ak (23 000)
Ao – 10 % (1 980)
Table I.2: Maximum load and no-load losses (in W) for three-phase dry-type medium power transformers with one winding with Um ≤ 24kV and the other with Um ≤ 3,6 kV
Maximum losses for kVA ratings that fall in between the ratings given in Table I.2 shall be obtained by linear interpolation.
Tier 1 (1 July 2015)
Tier 2 (1 July 2021)
Rated Power (kVA)
Maximum load losses Pk (W)
Maximum no-load losses Po (W)
Maximum load losses Pk (W)
Maximum no-load losses Po (W)
≤ 50
Bk (1 700)
Ao (200)
Ak (1 500)
Ao – 10 % (180)
100
Bk (2 050)
Ao (280)
Ak (1 800)
Ao – 10 % (252)
160
Bk (2 900)
Ao (400)
Ak (2 600)
Ao – 10 % (360)
250
Bk (3 800)
Ao (520)
Ak (3 400)
Ao – 10 % (468)
400
Bk (5 500)
Ao (750)
Ak (4 500)
Ao – 10 % (675)
630
Bk (7 600)
Ao (1 100)
Ak (7 100)
Ao – 10 % (990)
800
Ak (8 000)
Ao (1 300)
Ak (8 000)
Ao – 10 % (1 170)
1 000
Ak (9 000)
Ao (1 550)
Ak (9 000)
Ao – 10 % (1 395)
1 250
Ak (11 000)
Ao (1 800)
Ak (11 000)
Ao – 10 % (1 620)
1 600
Ak (13 000)
Ao (2 200)
Ak (13 000)
Ao – 10 % (1 980)
2 000
Ak (16 000)
Ao (2 600)
Ak (16 000)
Ao – 10 % (2 340)
2 500
Ak (19 000)
Ao (3 100)
Ak (19 000)
Ao – 10 % (2 790)
3 150
Ak (22 000)
Ao (3 800)
Ak (22 000)
Ao – 10 % (3 420)
Table I.3a
Correction factors to be applied to the load and no load losses indicated in Tables I.1, I.2 and I.6 for medium power transformers with special combinations of winding voltages (for rated power ≤ 3 150 kVA)
Special combination of voltages in one winding
Load losses (P k )
No load losses (P o )
For both liquid immersed (Table I.1) and dry type (Table I.2)
No correction
No correction
Primary highest voltage for equipment U m ≤ 24kV
Secondary highest voltage for equipment U m > 3,6 kV
For liquid immersed (Table I.1)
10 %
15 %
Primary highest voltage for equipment Um = 36kV
Secondary highest voltage for equipment Um ≤ 3,6 kV
Primary highest voltage for equipment Um = 36kV
Secondary highest voltage for equipment Um > 3,6 kV
10 %
15 %
For dry type (Table I.2)
10 %
15 %
Primary highest voltage for equipment Um = 36kV
Secondary highest voltage for equipment Um ≤ 3,6 kV
Primary highest voltage for equipment Um = 36kV
Secondary highest voltage for equipment Um > 3,6 kV
15 %
20 %
Table I.3b
Correction factors to be applied to the load and no load losses indicated in Tables I.1, I.2 and I.6 for medium power transformers with dual voltage in one or both windings differing more than 10 % and rated power ≤ 3 150 kVA.
The losses shall be calculated on the base of the voltage of the winding specified in the second column and can be increased with the correction factors given in the last 2 columns. In any case, whatever the combinations of winding voltages, the losses cannot exceed the values given in Tables I.1, I.2 and I.6 corrected by the factors in this table.
Type of dual voltage
Reference voltage for the application of correction factors
Load losses (Pk)
No load losses (Po)
Dual voltage on one winding with reduced power output on the lower low-voltage winding
AND
maximum available power on the lower voltage of the low-voltage winding limited to 0,85 of the rated power assigned to the low-voltage winding at its higher voltage.
losses shall be calculated based on the higher voltage of the low-voltage winding
No correction
No correction
Dual voltage on one winding with reduced power output on the lower high-voltage winding
AND
maximum available power on the lower voltage of the high-voltage winding limited to 0,85 of the rated power assigned to the high-voltage winding at its higher voltage.
losses shall be calculated based on the higher voltage of the high-voltage winding
No correction
No correction
Dual voltage on one winding
AND
full rated power available on both windings, i.e., the full nominal power is available regardless of the combination of voltages.
The losses shall be calculated based on the higher voltage of the dual voltage winding
10 %
15 %
Dual voltage on both windings
AND
rated power available on all combinations of windings, i.e., both voltages on one winding are fully rated in combination with one of the voltages on the other winding
the losses shall be calculated based on the higher voltages of both dual voltage windings
20 %
20 %

---
Source: https://www.legislation.gov.uk/eur/2014/548/annex/I/division/1/division/1.1 (the official version)
Page: https://openlegislation.uk/eu-regulation-2014-548/annex-I/division-1/division-1.1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.