Keystone KTAT-375-480-277 /A Step Down Transformer 480V to 277V

Typically ships in 2-3 business days* View full description
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Universal Voltage Converter Transformer | 480V-347V to 277V Autotransformer

Keystone KTAT-375-480-277 /A: Power Your 277V Lighting with Confidence

The Keystone KTAT-375-480-277 375W Step Down Auto Transformer is your solution for seamlessly integrating 277V lighting into your 480V power system. This innovative transformer enables you to utilize common universal voltage electronic ballasts, making your lighting setup more versatile and efficient.

Key Features:

  • 480V to 277V Step-Down: Convert 480V single-phase power to 277V, allowing you to use 277V electronic ballasts.
  • Non-Isolated Design: Offers a compact and cost-effective solution for voltage conversion.
  • Sound Rated A: Operates quietly, minimizing noise disturbances.
  • 5-Year Limited Warranty: Ensures long-lasting performance and peace of mind.
  • Universal Compatibility: Works with T5, T8, CFL, or Electronic HID ballasts operating at 277V input voltage.
  • High-Temperature Resistance: Features Class A insulation, rated for temperatures up to 105°C.
  • Safety Certified: UL and cUL 5085 approved for safe and reliable operation.
  • Thermal Protection: Built-in safety feature prevents overheating and ensures long-term reliability.


  • Expand your lighting options: Utilize a wider variety of 277V lighting fixtures and ballasts.
  • Simplify installation: No need for complex wiring or additional transformers.
  • Reduce energy costs: Utilize energy-efficient 277V electronic ballasts.
  • Enjoy long-lasting performance: Built with high-quality materials for dependable operation.
  • Ensure safety: Complies with stringent safety standards for peace of mind.

Ideal Applications:

  • Commercial buildings
  • Industrial facilities
  • Educational institutions
  • Healthcare facilities
  • Retail spaces
  • Parking garages
  • And more!

Upgrade your lighting system with the Keystone KTAT-375-480-277 375W Step Down Auto Transformer and experience the benefits of flexibility, efficiency, and reliability. Order yours today and unlock the full potential of your 480V power system!

Additional Information:

  • Input Voltage: 480V or 347V
  • Output Voltage: 277V
  • Frequency: 60Hz
  • Phase: Single-Phase
  • Dimensions: 5.7″ x 5.0″ x 3.7″
  • Weight: 6.6 lbs




*This product is built to order typically ships in 2 to 3 business days. Larger quantities may take longer than stated lead-time.  All lead-times are estimates and you will be notified by email if it will take longer than 5 business days to ship. Keystone has multiple warehouse's around the country to help serve you better.

Extra Information

Keystone Technologies
Catalog No:
KTAT-375-480-277 /A
Ballast Type:
Step Down Transformer
Input Voltage:
Output Voltage:
Input Frequency:
50/60 Hz
Height (in.):
Width (in.):
Length (in.):
5 Year
Price Shown:
Per Transformer