Current Transformers

Current transformers (CT) are devices that are used to transform the current from a high current into a lower current so that the power can then be measured and controlled. The transformers consist of a core, a primary and a secondary winding. When an alternating current flows through the primary winding, a magnetic flux is created which then induces an alternating current in the secondary winding. This alternating current is proportional to the current in its primary. Current transformers are also known as a "step-down transformers". Once the current has been reduced it can be safely monitored and measured using an ammeter.


Current transformers can perform circuit control and perform roles for safety protection and current limiting.


Current transformers are found in:


  • Generating stations,

  • Electrical substations

  • Commercial electric power distribution.

Types of Current Transformers


Toroidal Current Transformer - These transformers are shaped like a doughnut they do not contain a primary winding. Instead, the line that carries the current flowing in the network is threaded through a window or hole in the toroidal transformer. Toroidal transformers offer high efficiency with minimal excess noise and little excess leakage inductance.


Wound Current Transformer - The transformers primary winding is physically connected in series with the conductor that carries the measured current flowing in the circuit. The magnitude of the secondary current is dependent on the turns ratio of the transformer.


Bar-type Current Transformer – This type of current transformer uses the actual cable or bus-bar of the main circuit as the primary winding, which is equivalent to a single turn. They are fully insulated from the high operating voltage of the system and are usually bolted to the current carrying device.


...
Read more Read less

Filters

Viewing 21 - 40 of 744 products
Results per page
Description Price Current Ratio Inner Diameter Transformer Type Overall Height Overall Width Overall Depth Input Current Output Current Minimum Temperature Maximum Temperature Dimensions For Use With Mounting Type Series
RS Stock No. 171-8856
BrandRS PRO
PHP1,049.00
Each
units
10:5 62 x 40mm Clip Fit 78mm 62mm 40mm 10A 5 A -5°C +55°C 62 x 40 x 78 mm - Surface Mount -
RS Stock No. 171-8762
BrandRS PRO
PHP710.49
Each
units
300:5 21 x 10mm Clip Fit 65mm 45mm 40mm 300A 5 A -5°C +55°C 45 x 40 x 65 mm - Surface Mount -
RS Stock No. 171-8811
BrandRS PRO
PHP1,792.17
Each
units
800:5 80 x 12mm Clip Fit 126mm 104mm 45mm 800A 5 A -5°C +55°C 104 x 45 x 126 mm - Surface Mount -
RS Stock No. 171-8782
BrandRS PRO
PHP1,128.00
Each
units
125:5 30 x 11mm Clip Fit 78mm 62mm 40mm 125A 5 A -5°C +55°C 62 x 40 x 78 mm - Surface Mount -
RS Stock No. 124-3880
BrandRS PRO
PHP81.71
Each
units
- - - - - - 15A - -40°C +120°C 17.2 x 9.53 x 20.4 mm - PCB Mount -
RS Stock No. 171-8778
BrandRS PRO
PHP736.17
Each
units
500:5 30 x 10mm Clip Fit 70mm 50mm 31mm 500A 5 A -5°C +55°C 50 x 31 x 70 mm - Surface Mount -
RS Stock No. 171-8859
BrandRS PRO
PHP1,049.00
Each
units
30:5 62 x 40mm Clip Fit 78mm 62mm 40mm 30A 5 A -5°C +55°C 62 x 40 x 78 mm - Surface Mount -
RS Stock No. 171-8823
BrandRS PRO
PHP2,774.24
Each
units
3000:5 100 x 30mm Clip Fit 155mm 140mm 45mm 3kA 5 A -5°C +55°C 140 x 45 x 155 mm - Surface Mount -
RS Stock No. 171-8857
BrandRS PRO
PHP1,049.00
Each
units
15:5 62 x 40mm Clip Fit 78mm 62mm 40mm 15A 5 A -5°C +55°C 62 x 40 x 78 mm - Surface Mount -
RS Stock No. 171-8751
BrandRS PRO
PHP668.46
Each
units
60:5 21 x 10mm Clip Fit 65mm 45mm 40mm 60A 5 A -5°C +55°C 45 x 40 x 65 mm - Surface Mount -
RS Stock No. 171-8767
BrandRS PRO
PHP918.26
Each
units
- - - - - - - - - - - - - -
RS Stock No. 171-8830
BrandRS PRO
PHP1,691.78
Each
units
250:5 45mm Base Mounted 102.5mm 141mm 38mm 250A 5 A - - 141 x 38 x 102.5 mm MCCB Surface Mount -
RS Stock No. 173-0238
BrandRS PRO
PHP170.611
Each (In a Box of 220)
units
- - - - - - 50A - -40°C +85°C 23.8 x 11.12 x 23.8 mm - PCB Mount -
RS Stock No. 171-8770
BrandRS PRO
PHP988.00
Each
units
200:1 30 x 10mm - 70mm 50mm 30mm - - - - 50 x 30 x 70 mm - - -
RS Stock No. 171-8855
BrandRS PRO
PHP1,049.00
Each
units
5:5 62 x 40mm Clip Fit 78mm 62mm 40mm 5A 5 A -5°C +55°C 62 x 40 x 78 mm - Surface Mount -
RS Stock No. 171-8860
BrandRS PRO
PHP1,328.37
Each
units
40:5 74 x 45mm Clip Fit 98mm 74mm 45mm 40A 5 A -5°C +55°C 74 x 45 x 98 mm - Surface Mount -
RS Stock No. 124-3896
BrandRS PRO
PHP220.19
Each
units
- - - - - - 25A - -40°C +85°C 19 x 11.5 x 21.5 mm - - -
RS Stock No. 171-8754
BrandRS PRO
PHP1,005.42
Each
units
100:1 21 x 10mm - 65mm 45mm 40mm - - - - 45 x 40 x 65 mm - - -
RS Stock No. 173-0220
BrandRS PRO
PHP205.909
Each (In a Box of 140)
units
- - - - - - 25A - -40°C +85°C 19 x 11.5 x 21.5 mm - - -
RS Stock No. 171-8766
BrandRS PRO
PHP603.00
Each
units
125:5 30 x 10mm Clip Fit 70mm 50mm 31mm 125A 5 A -5°C +55°C 50 x 31 x 70 mm - Surface Mount -
Related Products
OMEGA 3 Phase current transformers are suitable for ...
Description:
OMEGA 3 Phase current transformers are suitable for primary ranges from 60 A to 630 A with 5 A secondary. The current transformers allow faster installation directly next to the moulded case circuit breakers for optimised use of space. • ...
RS Pro toroidal current sensors are fully encapsulated ...
Description:
RS Pro toroidal current sensors are fully encapsulated for optimal mounting to printed circuit boards. Commonly used to detect branch circuit overload, load drop or shut down, accurate and easy to use. These RS Pro current sensors operate as the ...
RS Pro offers these flying lead current transformers ...
Description:
RS Pro offers these flying lead current transformers with high output voltage and linearity in a small size. Integral flying for easy installation 24 AWG 300V rating 250 mm long. All materials UL94-V0. Large centre hole allows 6.3 mm tabs. ...
RS Pro high current transformers feature a primary ...
Description:
RS Pro high current transformers feature a primary current range 50-150A, 1% accuracy. These current transformers also have dielectric with stand voltage 4KVrms, operating frequency 50/60 Hz, rated burden resistance 33 Ω, all materials UL94-VO and operating temperature -40°C to ...