ELV LED lamps without an active switching power supply are considered to fulfil the
requirements of CISPR 15 without test.
All other types of retrofit ELV LED lamps shall be tested in conjunction with a
wound 50 or 60 Hz transformer. The use of such a transformer is considered to be the
worst-case condition and shall be used unless it is clearly stated in the manufacturer’s
instructions that the lamp is unsuitable for use with such a transformer. In this case
measurements shall be performed in combination with a typical compliant electronic
converter for halogen lamps.
The combination of transformer and LED lamp shall comply with the mains
disturbance voltage limits of Table 2a and the radiated disturbance limits of Tables 3a
and 3b.
In the case of the disturbance voltage measurement the lamp is mounted in a conical
metal housing as described in figure 7.The lamp is then connected to the transformer
by a flexible 3-core cable consisting of two ELV supply conductors and the earth
connection to the conical housing. The length of this cable shall be as short as
possible. The metal conical housing shall be positioned with its cable entrance close
to the transformer.
The combination of transformer and conical metal housing shall be tested as a
luminaire in accordance with the requirements of clause 8.2.
When performing the radiated disturbance measurements in accordance with clause 9,
the conical metal housing shall not be used.