Current Transformers for Metering

Introduction to Metering Current Transformers

Measuring Current Transformers (CTs) are used with the measuring instruments to:

  1.  Isolate the instruments from the power circuits,
  2.  Standardise the instruments, usually at 5 amps or 1 amp.

The scale of the instrument (according to the CT ratio), then becomes the only non-standard feature of the instrument.

If you require more information on Measuring class, please refer to our guide -> PDF

To help explain some of the terminology we use for our range of current transformers, we have produced a terminology section for your assistance.

How to choose your CT?

It can be difficult to pick the right CT for your application (especially if you do not have technical background). 

Here are some things we will need to know before we can provide a quotation for you:

  • Ratio
    • Primary
    • Secondary
  • Burden
  • Accuracy Class
  • Type 
  • Application - indoor/outdoor
  • Limiting Dimensions - CT has to fit on a busbar or in switchgear  

If you are still unsure how to choose your CT get in touch with us on +44(0)1355 236 057 or or our live Chat! 

Indoor Measuring Current Transformers

Whether the current transformer is taped, plastic case or resin enacapsulated models. Ring shape, square, rectangular or stadium style, we have a solution. Our quality range of medium voltage indoor transformers ensure that we can provide a full package service to our global customer base.

Indoor CTs

Outdoor Measuring Current Transformers

Covering Low Votlage ( LV ) & Medium Voltage ( MV ) insulation levels up to 145kV, our outdoor transformers can be supplied as resin encapsulated or enclosed in a metal enclosure. Suitable for several applications!

Outdoor CTs

Measuring Current Transformers in Oil

Designed for installation inside a power transformer, all materials have been specially selected to ensure transformer oil contamination is kept to a minimum.

CTs in Oil

SF6 and LS0H CTs

Every project is different, that's why we have developed a range of current transformers suitable for some of the most industrially challenging environments. Our instrument transformer range covers Low smoke and fume / Low smoke zero halegon, Sulphur Hexaflouride (sf6) or Gas insulated switchgear (GIS).