EN   EN 
 
 
 EUROPEAN  
COMMISSION   
Brussels, XXX  
[…](2018) XXX  draft  
ANNEX  
 
ANNEX  
to the  
Commission Regulation (EU) .../... of XXX  
amending 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  
  EN 1  EN ANNEX  
The Annexes  to Regulation (EU) No 548/2014  are amended as follows :  
(1) Annex I is amended as follows:  
(a) point 1 is amended as follows:  
(i) the following paragraphs are added:  
"As of the date of application of Tier 2 requirements (July 2021), when the one -to-one 
replacement of an existing medium power transformer entails disproportionate costs 
associated with their installation, the replacemen t transformer is, exceptionally, only required 
to meet Tier 1 requirements for the given rated power.  
In this respect, i t can be considered that installation costs are disproportionate if these costs 
(e.g. the replacement of the complete substation housin g 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 nor mal expected service life. This net present value should 
be calculated based on capitalised loss values using widely accepted social discount rates.  
In those cases where the replacement transformer is only capable of meeting Tier 1 
requirements instead of  Tier 2, the manufacturer or importer must state in the technical 
documentation of the transformer the following information obtained from the commissioner 
of the unit:  
– Address and contact details of the commissioner of the unit  
– The station where the repla cement unit is to be installed. This can be either a specific 
location or an specific installation type (e.g., station or cabin model)  
– The justification to install a unit that is only Tier 1 compliant. If the unit(s) were 
commissioned by a tendering proces s, this shall include all the necessary information 
regarding the analysis of bids and the award decision, but not information that may 
be commercially sensitive for bidders. ", 
 
(ii) 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 ≤ 3150 kVA)  
Special combination of voltages in one winding  Load losses 
(Pk) 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 > 3.6kV  
For liquid immersed (Table I.1)  10% 15% 
Primary highest voltage for 
equipment Um = 36kV  Secondary highest voltage for 
equipment Um ≤ 3.6kV  EN 2  EN Primary highest voltage for 
equipment Um = 36kV  Secondary highest voltage for 
equipment Um > 3.6kV  10% 15% 
For dry type (Table I.2)  10% 15% 
Primary highest voltage for 
equipment Um = 36kV  Secondary highest voltage for 
equipment Um ≤  3.6kV  
Primary highest voltage for 
equipment Um = 36kV  Secondary highest voltage for 
equipment Um > 3.6kV  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 ≤ 3150 kVA.  
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 rega rdless 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  the losses shall be 
calculated based on 20% 20% EN 3  EN rated power available on all 
combinations of windings, i.e., both 
voltages on one wi nding are fully 
rated in combination with one of the 
voltages on the other winding  the higher voltages 
of both dual voltage 
windings  
(*) 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. ", 
(b) in point 1.4,  the first paragraph is replaced as follows:  
"1.4. For the one -to-one replacement of existing medium power pole -mounted transformers, 
the applicable maximum levels of load and no -load losses are not the one s in Tables I.1 and 
I.2, but those in Table I.6 below. The correction factors for special combinations of winding 
voltages indicated in Tables I.3a an d I.3b are also applicable. " , 
(c) point 2 is replaced by the following:  
"2. Minimum energy efficiency req uirements for large power transformers  
Minimum efficiency requirements for three -phase large power transforme rs are set out in 
Tables I.7,  I.8 and I.9 . 
As of the date of application of Tier 2 requirements (July 2021), when the one -to-one 
replacement of an existing large power transformers or the installation of a new large power 
trans former in an existing  site entails disproportionate costs associated to its transportation 
and/or i nstallation, or is technically i nfeasible, the replacement transformer is, ex ceptionally, 
only required to meet Tier 1 requirements for the given rated power.  
Furthermore, if the cost involved in meeting Tier 1 requirements also proves to be 
disproportionate, or where it is demonstrated in the technical documentation that no 
techn ically feasible solutions exist, no minimum requirements would be applicable for the 
one-to-one replacement  of a large power transformer in an existing  site. 
As of the date of application of Tier 2 requirements (July 2021), when the installation of a 
new l arge power transformer in a new site entails disproportionate costs associated to their 
transportation and/or i nstallation, or is technically i nfeasible, the new transformer is, 
exceptionally, only required to meet Tier 1 requirements for the given rated p ower.  
Furthermore, i f the cost involved in meeting Tier 1 requirements also proves to be 
disproportionate, or where it is demonstrated in the technical documentation that no 
technically feasible solutions exist, no minimum requirements would be applicable for new 
large power transformers  installed in new sites.  
In those cases where a replacement or a new large power transformer is not capable of 
meeting Tier 2 requirements, or not even Tier 1 ones , the manufacturer or importer 
responsible for placing on th e market or putting  into service the transformer  must state in the 
technical documentation  the following information obtained from the commissioner of the 
unit: 
– Address and contact details of the commissioner of the unit  
– The station where the replacement unit is to be installed. This can be either a specific 
location or an specific installation type (e.g., station or cabin model)  EN 4  EN – The technical and/or economic justification to install a unit that is only Tier 1 
compliant (or not even able to meet Tier 1 req uirements for new transformers). If the 
unit(s) were commissioned by a tendering process, this shall include all the necessary 
information regarding the analysis of bids and the award decision, but not 
information that may be comme rcially sensitive for bid ders.  
In all the above  cases, the complete technical documentation  must systematically be submitted  
to the competent national market surveillance authorities every time that a non-compliant  
transformer is placed on the market or put into service.  
 
Table I.7 Minimum Peak Efficiency Index requirements for liquid immersed large 
power transformers  
Rated Power (MVA)  Tier 1 (01.07.2015)  Tier 2 (01.07.2021)  
Minimum Peak Efficiency Index (%)  
≤ 0.025  97.742  98.251  
0.05 98.584  98.891  
0.1 98.867  99.093  
0.16 99.012  99.191  
0.25 99.112  99.283  
0.315  99.154  99.32  
0.4 99.209  99.369  
0.5 99.247  99.398  
0.63 99.295  99.437  
0.8 99.343  99.473  
1 99.360  99.484  
1.25 99.418  99.487  
1.6 99.424  99.494  
2 99.426  99.502  
2.5 99.441  99.514  
3.15 99.444  99.518  
4 99.465  99.532  
5 99.483  99.548  
6.3 99.51  99.571  
8 99.535  99.593  
10 99.56  99.615  
12.5 99.588  99.64  
16 99.615  99.663  
20 99.639  99.684  
25 99.657  99.7 
31.5 99.671  99.712  
40 99.684  99.724  EN 5  EN 50 99.696  99.734  
63 99.709  99.745  
80 99.723  99.758  
100 99.737  99.77  
125 99.737  99.78  
160 99.737  99.79  
200 99.737  99.797  
Minimum PEI values for kVA ratings that fall in between the ratings given in Table I.7 shall 
be calculated by linear interpolation  
 
Table I.8 Minimum Peak Efficiency Index requirements for dry -type large power 
transformers with Um ≤ 36kV  
Rated Power (MVA)  Tier 1 (01.07.2015)  Tier 2 (01.07.2021)  
Minimum Peak Efficiency Index (%)  
3,15 < Sr ≤ 4  99.348  99.382  
5 99.354  99.387  
6,3 99.356  99.389  
8 99.357  99.390  
≥ 10 99.357  99.390  
Minimum PEI values for kVA ratings that fall in between the ratings given in Table I.8 shall 
be calculated by linear interpolation ", 
 
Table I.9  Minimum Peak Efficiency Index requirements for dry -type large power 
transformers with Um > 36kV  
Rated Power (MVA)  Tier 1 (01.07.2015)  Tier 2 (01.07.2021)  
Minimum Peak Efficiency Index (%)  
≤ 0.05  96.174  96.59  
0.1 97.514  97.79  
0.16 97.792  98.016  
0.25 98.155  98.345  
0.4 98.334  98,57  
0.63 98.494  98.619  
0.8 98.677  98.745  
1 98.775  98.837  
1.25 98.832  98.892  
1.6 98.903  98.96  
2 98.942  98.996  
2.5 98.933  99.045  EN 6  EN 3.15 99.048  99.097  
4 99.158  99.225  
5 99.2 99.265  
6.3 99.242  99.303  
8 99.298  99.356  
10 99.33  99.385  
12.5 99.37  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 99.59  99.626  
Minimum PEI values for kVA ratings that fall in betwee n the ratings given in Table I.9  shall 
be calculated by linear interpolation ", 
(d) in point 3, a new point (f)  is added as follows:  
"(f) the noise levels of medium and large power transformers, measured at least as a type test  
and the last subparagraph is replaced by:   
For medium and la rge power transformers only, the information under a); c) and d) shall also 
be included on the rating plate of the transformer. "; 
(e) point 5 is added as follows:  
"5. Repair operations  
Existing m edium and large power transformers shall be considered as new products if they are 
subject to upgrade or retrofit activities , regardless of when they were first placed on the 
market . This is without prejudice to the legal obligations under other U nion's  harmonisation 
legislation that these produc ts could be subje ct to.  
Existing m edium and large p ower transformers on which only routine repair or refurbishment 
operations ar e performed shall not  be considered as new products.  Therefore, obligations set 
out in this Annex are not applicable to repaired or refurbished transformers, which were first 
placed on the market before 11 June 2014. "   
 
(2) Annex II is replaced  by the following : 
 
"Annex II  
Measurement method s 
For the purpose of compliance with the requirements of this Regulation, measurements shall 
be made using a reliable, accurate and reproducible measurement procedure, which takes into 
account the generally recognised state of the art measurement methods, including methods set 
out in documents the reference numbers of which have been published for that purpose in the 
Official Journal of the European Union. " EN 7  EN (3) In Annex III the follow ing paragraph is added : 
"If Factory Acceptance Tests (FATs) are planned, which test minimum requirements set out 
in Annex I of this Regulation, the competent authorities in may deci de to use witnessed 
testing during these FATs to assess compliance of the transformer under investigation or have 
an independent test house carry out such assessment on their behalf. The authorities may 
request a manufacturer to disclose information on any  planned FATs relevant for witnessed 
testing. " 
(4) in Annex IV , point (c)  is amended as follows:  
"(c) Medium power transformers with amorphous steel core: Ao -50%, Ak ".