UL 2763:2011 free download Energy Efficient Harmonic Cancellation Transformers
1 Scope
1.1 This standard is designed to reduce environmental impacts by specifying criteria for energy efficientharmonic cancellation transformers.
1.2 This standard is a republication of Ecologo Certification Criteria Document (CCD)015: EnergyEfficient Harmonic Cancellation Transformers. The criteria have been reformatted for consistency with theStyle Manual for uL Standards.
2 Glossary
2.1 For the purpose of these requirements, the following definitions apply.
2.2CFC’s -Chlorofluorocarbons.
2.3 ELECTRIC TRANSFORMERS – A device that converts electricity from the high voltage levels inthe utility transmission systems to voltages that can be safely used in businesses and homes.
2.4 HARMONICS – Integral multiples of the base, or fundamental frequency (60 Hz in North America)in the electrical distribution system.For example the 3rd harmonic is 3 x 60 Hz = 180 Hz.
COMPLIANCE EVALUATION
3 Energy Efficient Harmonic Cancellation Transformers Requirements3.1 Energy efficient harmonic cancellation transformers shall:
a) Be Energy Star Transformers Program Compliant;
b) Be subjected to performance testing in accordance with the requirements of NEMA TP1-1996,Guide for Determining Energy Efficiency for Distribution Transformers;
c) Ensure that,when providing transformers with 3-phase, 4-wire output(s) for balanced, phase-to-neutral, non-linear loads, the output winding configuration cancels the principal triplen
harmonic fluxes (3rd and 9th) created by the load currents without coupling them to the primarywinding;
d) Not be manufactured using chlorofluorocarbons (CFCs) in any phase of the manufacturingprocess; and
UL 2763:2011 free download
