Medium power transformers shall comply with the maximum allowed load and no-load losses or the Peak Efficiency Index (PEI) values set out in Tables I.1 to I.5, excluding medium power pole-mounted transformers, which shall comply with the maximum allowed load and no load losses values set out in Table I.6.
| a 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)a | Maximum no-load losses Po (W)a | Maximum load losses Pk (W)a | Maximum no-load losses Po (W)a |
| ≤ 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 % (180) |
| 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) |
| a 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)a | Maximum no-load losses Po (W)a | Maximum load losses Pk (W)a | Maximum no-load losses Po (W)a |
| ≤ 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) |
| One winding with Um ≤ 24 kV and the other with Um > 1,1 kV | The maximum allowable losses in Tables I.1 and I.2 shall be increased by 10 % for no load losses and by 10 % for load losses |
| One winding with Um = 36 kV and the other with Um ≤ 1,1 kV | The maximum allowable losses in Tables I.1 and I.2 shall be increased by 15 % for no load losses and by 10 % for load losses |
| One winding with Um = 36 kV and the other with Um > 1,1 kV | The maximum allowable losses indicated in Tables I.1 and I.2 shall be increased by 20 % for no load losses and by 15 % for load losses |
| Case of dual voltage on one winding | In case of transformers with one high-voltage winding and two voltages available from a tapped low-voltage winding, losses shall be calculated based on the higher voltage of the low-voltage winding and shall be in compliance with the maximum allowable losses in Tables I.1 and 1.2. The maximum available power on the lower voltage of the low-voltage winding on such transformers shall be limited to 0,85 of the rated power assigned to the low-voltage winding at its higher voltage. |
| In case of transformers with one low-voltage winding with two voltages available from a tapped high-voltage winding, losses shall be calculated based on the higher voltage of the high-voltage winding and shall be in compliance with the maximum allowable losses in Tables I.1 and I.2., The maximum available power on the lower voltage of the high-voltage winding on such transformer shall be limited to 0,85 of the rated power assigned to the high-voltage winding at its higher voltage. | |
| If the full nominal power is available regardless of the combination of voltages, the levels of losses indicated in Tables I.1 and I.2 can be increased by 15 % for no load losses and by 10 % for load losses. | |
| Case of dual voltage on both windings | The maximum allowable losses in Tables I.1 and I.2 can be increased by 20 % for no load losses and by 20 % for load losses for transformers with dual voltage on both windings. The level of losses is given for the highest possible rated power and on the basis that the rated power is the same regardless of the combination of voltages. |
| Rated Power (kVA) | Tier 1 (1 July 2015) | Tier 2 (1 July 2021) |
|---|---|---|
| Minimum Peak Efficiency Index (%) | ||
| 3 150 < Sr ≤ 4 000 | 99,465 | 99,532 |
| 5 000 | 99,483 | 99,548 |
| 6 300 | 99,510 | 99,571 |
| 8 000 | 99,535 | 99,593 |
| 10 000 | 99,560 | 99,615 |
| 12 500 | 99,588 | 99,640 |
| 16 000 | 99,615 | 99,663 |
| 20 000 | 99,639 | 99,684 |
| 25 000 | 99,657 | 99,700 |
| 31 500 | 99,671 | 99,712 |
| 40 000 | 99,684 | 99,724 |
Minimum PEI values for kVA ratings that fall in between the ratings given in Table I.4 shall be calculated by linear interpolation.
| Rated Power (kVA) | Tier 1 (1 July 2015) | Tier 2 (1 July 2021) |
|---|---|---|
| Minimum Peak Efficiency Index (%) | ||
| 3 150 < Sr ≤ 4 000 | 99,348 | 99,382 |
| 5 000 | 99,354 | 99,387 |
| 6 300 | 99,356 | 99,389 |
| 8 000 | 99,357 | 99,390 |
| ≥ 10 000 | 99,357 | 99,390 |
Minimum PEI values for kVA ratings that fall in between the ratings given in Table I.5 shall be calculated by linear interpolation.
The maximum allowable levels of losses set out in Tables I.1 and I.2 shall be increased by 20 % for no load losses and 5 % for load losses in Tier 1 and by 10 % for no load losses in Tier 2.
The levels of load and no load losses indicated in Tables I.1 and I.2 are not applicable to liquid immersed pole-mounted transformers with power ratings between 25 kVA and 315 kVA. For these specific models of medium power pole-mounted transformers, the maximum levels of allowable losses are set out in Table I.6.
| a Maximum allowable losses for kVA ratings that fall in between the ratings given in Table I.6 shall be obtained by linear interpolation. | ||||
| Tier 1 (1 July 2015) | Tier 2 (1 July 2021) | |||
|---|---|---|---|---|
| Rated Power (kVA) | Maximum load losses (in W)a | Maximum no-load losses (in W)a | Maximum load losses (in W)a | Maximum no-load losses (in W)a |
| 25 | Ck (900) | Ao (70) | Bk (725) | Ao (70) |
| 50 | Ck (1 100) | Ao (90) | Bk (875) | Ao (90) |
| 100 | Ck (1 750) | Ao (145) | Bk (1 475) | Ao (145) |
| 160 | Ck + 32 % (3 102) | Co (300) | Ck + 32 % (3 102) | Co – 10 % (270) |
| 200 | Ck (2 750) | Co (356) | Bk (2 333) | Bo (310) |
| 250 | Ck (3 250) | Co (425) | Bk (2 750) | Bo (360) |
| 315 | Ck (3 900) | Co (520) | Bk (3 250) | Bo (440) |
The minimum efficiency requirements for large power transformers are set out in Tables I.7 and I.8.
| Rated Power (MVA) | Tier 1 (1 July 2015) | Tier 2 (1 July 2021) |
|---|---|---|
| Minimum Peak Efficiency Index (%) | ||
| ≤ 4 | 99,465 | 99,532 |
| 5 | 99,483 | 99,548 |
| 6,3 | 99,510 | 99,571 |
| 8 | 99,535 | 99,593 |
| 10 | 99,560 | 99,615 |
| 12,5 | 99,588 | 99,640 |
| 16 | 99,615 | 99,663 |
| 20 | 99,639 | 99,684 |
| 25 | 99,657 | 99,700 |
| 31,5 | 99,671 | 99,712 |
| 40 | 99,684 | 99,724 |
| 50 | 99,696 | 99,734 |
| 63 | 99,709 | 99,745 |
| 80 | 99,723 | 99,758 |
| ≥ 100 | 99,737 | 99,770 |
Minimum PEI values for MVA ratings that fall in between the ratings given in Table I.7 shall be calculated by linear interpolation.
| Rated Power (MVA) | Tier 1 (1 July 2015) | Tier 2 (1 July 2021) |
|---|---|---|
| Minimum Peak Efficiency Index (%) | ||
| ≤ 4 | 99,158 | 99,225 |
| 5 | 99,200 | 99,265 |
| 6,3 | 99,242 | 99,303 |
| 8 | 99,298 | 99,356 |
| 10 | 99,330 | 99,385 |
| 12,5 | 99,370 | 99,422 |
| 16 | 99,416 | 99,464 |
| 20 | 99,468 | 99,513 |
| 25 | 99,521 | 99,564 |
| 31,5 | 99,551 | 99,592 |
| 40 | 99,567 | 99,607 |
| 50 | 99,585 | 99,623 |
| ≥ 63 | 99,590 | 99,626 |
Minimum PEI values for MVA ratings that fall in between the ratings given in Table I.8 shall be calculated by linear interpolation.
From 1 July 2015, the following product information requirements for transformers included in the scope of this Regulation (Article 1) shall be included in any related product documentation, including free access websites of manufacturers:
information on rated power, load loss and no-load loss and the electrical power of any cooling system required at no load;
for medium power (where applicable) and large power transformers, the value of the Peak Efficiency Index and the power at which it occurs;
for dual voltage transformers, the maximum rated power at the lower voltage, according to Table I.3;
information on the weight of all the main components of a power transformer (including at least the conductor, the nature of the conductor and the core material);
For medium power pole mounted transformers, a visible display ‘For pole-mounted operation only’.
The information under a); c) and d) shall also be included on the rating plate of the power transformers.
The following information shall be included in the technical documentation of power transformers:
manufacturer's name and address;
model identifier, the alphanumeric code to distinguish one model from other models of the same manufacturer;
the information required under point 3.
If (parts of) the technical documentation is based upon (parts of) the technical documentation of another model, the model identifier of that model shall be provided and the technical documentation shall provide the details of how the information is derived from the technical documentation of the other model, e.g. on calculations or extrapolations, including the tests undertaken by the manufacturer to verify the calculations or extrapolations undertaken.