Current Transformers

Requirements and Specifications

The customer shall supply current transformers when the service is metered at the transformer and when the transformer is installed in an enclosure. Contact Austin Energy Metering for verification at 512-505-7045.

Current Transformer Description
Possible window type current transformer ratios:
  • 600/5 with rating factor 2.0(min) at 55 degree C
  • 2000/5 with rating factor 1.5(min) at 55 degree C
  • 4000/5 with rating factor 1.0(min) at 55 degree C
All Current Transformers shall be high accuracy with extended range: Class 0.15 accuracy at B0.1, 0.2, 0.5 and up to 1.8 burden at 60 cycles for all ratings.  AE specification E-0746 (pdf)

Requirements for 5th Terminal Lugs in Meter Socket

  • Services that require the voltage of 120/208 Single Phase shall have a 5th terminal lug installed in the 9 o’clock position.
  • Services that require the voltage of 125/216 single phase shall have a 5th terminal lug installed in the 9 o’clock position in the metering socket.
  • The 5th terminal lug is purchased in addition to the socket being purchased. It is only required for single phase 120/208 and 125/216
    volt services.
  • Meter sockets requiring the 5th lug terminal shall be identical to the sockets specified with the exception that it has the 5th lug terminal installed.

Other Specifications



Date last reviewed or modified: 07/07/2021