Application Description A Mini Power Center combines three individual components into one NEMA Type 3R enclosure: a main
breaker, an encapsulated single-phase (Type EP) or three-phase (EPT) Dry-Type Trans-former, and a secondary distribution
loadcenter with main breaker. Inter-connecting wiring is completed at the factory. Mini Power Centers are used wherever there
is a 480V or 600V distribution system and loads requiring 208Y/120V, three-phase or 120/240V single-phase.
Typical installations include:
Features, Benefits and Functions
- Industrial plant assembly lines
- Plant expansions
- Test equipment
- Temporary power at construction sites
- Sewage disposal plants
- Car washes
- Parking lots
- Commercial buildings
Standards and Certifications Industry Standards
- Suitable for service entrance
- Sand and Resin Encapsulated design
- Suitable for indoor or outdoor applications NEMA 3R
- 185°C Insulation system, 115°C Rise standard
- 60 Hz operation
- Primary main breaker
- Secondary main breaker (Type BR feeder breakers not included)
- All live parts enclosed for personnel safety
- Cover is hinged to prevent removal and can be padlocked
- Cores are grounded with a copper lead
- Ground bar is supplied to permit grounding of individual secondary circuits
- Neutral bar is grounded to case
- Feeder circuits can be easily added or changed using Type BR plug-in breakers
- Aluminum windings and loadcenter chassis standard
- Short-term overload capability as required by ANSI
- Meets NEMA ST-20 sound levels
- CSA/UL Listed
All dry type distribution and control transformers are built and tested in accordance with applicable NEMA, ANSI, and IEEE
Standards. All 600 volt class transformers are CSA and UL listed unless otherwise noted.
All dry type distribution transformers are seismically tested, seismically qualified, and exceed requirements of
the Uniform Building Code (UBC) and California Code Title 24.
Eaton standard dry type distribution transformers are designed for 60 Hertz operation. Transformers required for other
frequencies must be specifically designed.
- Overload Capability
Short-term overload is designed into transformers as required by ANSI. Dry type distribution transformers will deliver 200%
nameplate load for one-half hour; 150% load for one-hour; and 125% load for four-hours without being damaged provided that a
constant 50% load precedes and follows the overload. See ANSI C57.96-01.250 for additional limitations. Continuous overload
capacity is not deliberately designed into a transformer because the design objective is to be within the allowed winding
temperature rise with nameplate loading.
- Insulation System and Temperature Rise
The design life of transformers having different insulation systems is the same — the lower temperature systems are designed
for the same life as the higher temperature systems.
- Winding Terminations
Eaton recommends external cables be rated 90°C (sized at 75°C ampacity) for encapsulated designs and 75°C for ventilated