Encompass™ Current Transformers from GE offer electrical utilities piece of mind knowing they’ll have the right CT in stock. Upgrade today and eliminate the need for multiple current ratios, thereby simplifying CT selection.
Encompass wide range CTs are designed for commercial and industrial applications. Encompass CT’s substantially reduce inventory, complexity and improve standardization for meter shop operations, particularly when used with GE’s kV2c FITZALL™ transformer rated meters.
JCR-0W, 10A-1000A, 2” Window, Indoor/Outdoor
JAK-0W, 20A-2000A, 3” Window, Indoor/Outdoor
JAB-0W, 20A-3000A, 4.5” x 3.5” Window, specifically designed for secondary bushing of padmount transformers
JAD-0W, 40A-4500A, 5.75” Window, Indoor/Outdoor
Meets IEEE C57.13 definition of 0.3 Standard Revenue Metering accuracy class, with additional extended range performance capability
The same ANSI mounting provisions, terminals, construction as standard CT’s
Reduce inventory requirements
Reduce part numbers
Simplify CT selection
Simplify billing multipliers
Application Overview: Secondary Metering with Current Transformers
Encompass and RevenueSense CTs provide flexibility for commercial and industrial applications, indoor or outdoor service and bar-type or window-type configurations.
Redefining the Test Limits
Traditionally, CT accuracy is tested at:
10% of rated current (light load)
100% of rated current (full load)
With a rating factor between 1.0 and 4.0.
With GE Encompass CT’s, the 0.3 accuracy class is extended by changing the test points to:
4% of rated current (light load)
40% of rated current (full load)
With a typical rating factor of 4.0
Wide Range Designed for CL20 Meter
A rating factor of 4.0 means the Current Transformer meets rated accuracy at up to 4 times the rated primary current. Thus, the output on a 5 Amp CT secondary can be used up to 20 Amps if a rating factor of 4.0 is assigned to the CT (4.0*5A = 20A). This pairs the CT output range and the Meter input range when used with a CL20 transformer rated meter, maximizing the performance potential of the system.
Standard CT Test Limits
Encompass Test Limits
Results and Benefits
The 4% and 40% test points in combination with a high rating factor of 4.0 means 1 Encompass CT can equal or better the performance of both higher AND lower ratios.
The 500:5 Encompass unit when compared to a 200:5 standard CT has equal to or better test results at all points included even low currents and is available at an equivalent price. This comparison holds true across several other standard CT ratios, meaning one Encompass CT can functionally replace up to eight other standard ratios, allowing for an inventory reduction of up to nearly 90%.
Encompass CT vs. Standard CT
To demonstrate the advantages of upgrading to an Encompass CT,
let’s compare a JAK-0W 500:5 Encompass CT to a JAK-0C 200:5 standard CT
Physically, the JAK-0W 500:5 Encompass CT:
Has the exact same mounting plate
Has the exact same terminal locations
Has the exact same window size
Electrically, the accuracy of a JAK-0W 500:5 is equivalent or better than the accuracy of a JAK-0C 200:5 across all test points. This can be looked at two ways:
A 500:5 Encompass CT has ±0.3% accuracy from 200A to 2000A, compared to a standard 200:5 CT which has a ±0.3% accuracy from 200A to only 800A. Both CT’s have ±0.6% accuracy from 20A to 200A.
The 500:5 Encompass CT has equal to or better accuracy rating across the entire 20A to 2000A range. It is important to note that accuracy class only defines the “tolerance of error” allowed in a CT. Actual test results are also an important factor when evaluating CT’s. At a typical burden of B-0.1, the Encompass CT test results slightly outperform a standard CT, even at the lowest test amps. All Encompass test results are well within the IEEE limits.
* Tested Accuracy Class values shown are for illustrative purposes only, and not a guarantee of performance. Actual results may vary, within defined test tolerances.
Make & Model
GE JCR-0C or JCW-0C
ABB CSF or CSH
Itron R6M or R6SA
GEC Durham TCW or TFW
100:5, 200:5, 300:5, 400:5, 500:5
GEC Durham AB