(a)

point 1 is amended as follows: (i) the title of Table I.1 is replaced as follows: ‘Maximum load and no-load losses (in W) for three-phase liquid-immersed medium power transformers with one winding with Um ≤ 24kV and the other with Um ≤ 3,6 kV’; (ii) the title of Table I.2 is replaced as follows: ‘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’; (iii) the following paragraphs are added after the first paragraph: ‘As of the date of application of Tier 2 requirements (1 July 2021), when the one-to-one replacement of an existing medium power transformer entails disproportionate costs associated with their installation, the replacement transformer is, exceptionally, only required to meet Tier 1 requirements for the given rated power. In this respect, installation costs are disproportionate if the costs of the replacement of the complete substation housing the transformer and/or the acquisition or rental of additional floor space are higher than the net present value of the additional avoided electricity losses (tariffs, taxes and levies excluded) of a Tier 2 compliant replacement transformer over its normally expected service life. The net present value shall be calculated based on capitalised loss values using widely accepted social discount rates (*1). In this case, the manufacturer, importer, or authorised representative shall include in the technical documentation of the replacement transformer the following information: — Address and contact details of the commissioner of the replacement transformer — The station where the replacement transformer is to be installed. This shall be unequivocally identified by either a specific location or a specific installation type (e.g., station or cabin model) — The technical and/or economic justification of the disproportionate cost to install a transformer that is only Tier 1 compliant instead of a Tier 2 compliant one. If the transformers(s) were commissioned by a tendering process, all the necessary information regarding the analysis of bids and the award decision shall be provided. In the above cases, the manufacturer, importer or authorised representative shall notify the competent national market surveillance authorities. ( *1 ) The European Commission Better Regulation Toolbox suggest using a value of 4 % for the social discount rate https://ec.europa.eu/info/sites/info/files/file_import/better-regulation-toolbox-61_en_0.pdf ’; " (iv) Table I.3 is replaced by Tables I.3a and I.3b as follows: ‘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 (Pk) No load losses (Po) For both liquid immersed (Table I.1) and dry type (Table I.2) No correction No correction Primary highest voltage for equipment Um ≤ 24kV Secondary highest voltage for equipment Um > 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. Type of dual voltage Reference voltage for the application of correction factors Load losses (Pk) (*2) No load losses (Po) (*2) 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 %