Current Transformer - Imag Specifation
Current Transformer - Imag Specifation
(OP)
Why is that Magnetizing current ( Imag ) measured or Specified mostly at Vk /2 (Vk= Knee point Voltage ) in the Current Transformer discription ?
When was the last time you drove down the highway without seeing a commercial truck hauling goods?
Download nowINTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
Current Transformer - Imag Specifation
|
RE: Current Transformer - Imag Specifation
RE: Current Transformer - Imag Specifation
A bit more info is needed.
RE: Current Transformer - Imag Specifation
I've seen Iexc limited at Vkp/2, but it's very rare. My assumption when that was specified was that someone was trying to spec a CT to match exactly to an existing unit and took it to another level above Iexc @ Vkp.
RE: Current Transformer - Imag Specifation
@ Scottf : Some manufcaturer specify it Imag ( magnetising Current ) at Vk (Knee Point Voltage ) and Few at Vk/2 . But These are for new substations and not matching any other existing CT
RE: Current Transformer - Imag Specifation
I have never seen it yet specified at a fraction of Vk but the standard allows for it. The reason why Ie is specified in this way is to ensure matched characteristics at Vk for a group of CT's used for a differential application. Matched characteristics minimises the spill current due to CT mismatches. In other words, it is intended to ensure superior performance than say if a Class P CT was used for the same application.
Alternatively stated the B-H characteristic passes through the same point for the matched CT's.