IEEE Standards IEEE C57.13.1-2017 pdf free download – IEEE Guide for Field Testing of Relaying Current Transformers IEEE C57.13.1-2017 pdf free download - IEEE Guide for Field Testing of Relaying Current Transformers. 12. Excitation test 12.1 Safety Ensure that the CT is de-energized and that the CT has been de-magnetized. Applying voltage to a... 02-24 Download Now