How to choose Current Transformer (CT)
Choosing a current transformer
Choice of a CT depends on 2 criteria:
- the Ip/5 A ratio
- the installation type.
The Ip/5 A ratio
We recommend that you choose the ratio immediately higher than the maximum measured current (In).
Example: In = 1103 A; ratio chosen = 1250/5.
For small ratings from 40/5 to 75/5 and for an application with digital devices, we recommend that you choose a higher rating, for example 100/5.
This is because small ratings are less accurate and the 40 A measurement, for example, will be more accurate with a 100/5 CT than with a 40/5 CT.
The installation type
Choice of a CT model depends on the installation type:
- insulated cables
- mounting on bars.
Released for: Schneider Electric Thailand
Need help?
Product Selector
Quickly and easily find the right products and accessories for your applications.
Get a Quote
Start your sales inquiry online and an expert will connect with you.
Where to buy?
Easily find the nearest Schneider Electric distributor in your location.
Help Center
Find support resources for all your needs, in one place.