How to do current measurement of 3-phase 220V motor using CT?

[garg29]

hi friends,

I want to measure current consumed by a 3-Phase 220v motor. I can do AC current measurements using CT(Current transformers) but i just want to know do i need to install only one CT or do i need 3 CT's one for each phase. What calculations are involved in finding out the net result.

Is it :- Itotal = (Sqrt(3)) * Iphase

Thanks in advance.

With best regards,
Garg

 

[nandhu015]

Re: Current Measurements

Yes, You have to measure all the three phases.

Regards
Nandhu

 

[mg_designs]

Current Measurements

eed 3 CT's one for each phase


review ur device datasheet for help u

i used ade7754 & is very good for 3 phase
current voltage power
try it

Added after 52 seconds:

ade7754 & is very good for 3 phase measurments
and very cheap

 

[alberto1683]

some problems with measurements

Hello friends. I`m working with ADE7754 , I read the VRMS value of phase A but it

have an error of 4%. Do you have the same problem??(I wrote -5 at AVRMSOS and I

measured with zero crossing detection)

Also I want to measure current but I don´t know what current transformer buy..

I`m greatfull with your help

Thanks

 

[Prabakaran]

Current Measurements

Hi mg_designs,
I too working in ADE7758 for calculating the power of the three phase motor , but i m facing problem in that. Can i have the code to calculate the power in that .

 

[alberto1683]

Re: Current Measurements

Hello Friends:

I´m working with a project with an ADE7754. I know what type of

Current Transformer did you use...

I have one CT that`s 2000:1, but I dont´t know the value of RB in the

circuitry

Thanks

 

[vijaya_narayana]

Re: Current Measurements

if it is for 3 phase then i think u need to have 3 CT to measure the current

 

[jayavardhan]

Current Measurements

use maxim4372 it gives very accuratevalue than CT.