Low-Voltage Current Transformers / Extended Range Current Transformers (ERCTs) for Billing, Window-Type
ROS-A Series
For 600V (max.) power systems, these current transformers offer a 0.3 Metering Class accuracy. ERCT specifications also available. Secondary side includes a short-circuiting device. Terminal cover sealable. Various window diameters and current ratios.
About the Product
Resin-insulated current transformers ROS-A Series, designed for billing purposes and suited to power systems of 600V (max.), offer revenue metering of at least a Class 0.3 Accuracy and can be used for indoor application or in an outdoor enclosure. Current Ratios available are from 100:5A to 800:5A, and window diameter options are 38mm, 66mm, and 78mm. ROS-A Series current transformers of the Standard Specifications have an RF of up to 4.0. Those of the ERCT Specifications are able to maintain the rated accuracy and burden rating while measuring 1% ~ 150% of the rated current, surpassing the usual metering-class requirement (5% ~ 100%). All ROS-A Series current transformers have been type-tested by CIC’s Advanced Electricity Lab, a testing facility accredited by a member of ILAC.
Product Features
- Standards: IEEE C57.13
- Secondary side equipped with a short-circuiting device
- Terminal cover provided for the secondary side
- Sealable
- Application: Indoors, or in an outdoor enclosure
- Rated Voltage: Up to 0.72 kV
- Frequency: 50 or 60 Hz
- 0.3 Metering Class
- Type-tested by a laboratory accredited by an ILAC member
- Additional specification or customization may be requested to comply with various electrical standards and client requirements
Selection Table
Standard Specifications
Model | Current Ratio | RF | Accuracy & Burden (IEEE) | Window Diameter | Approx. Weight | |
At 30℃ Ambient Temperature | At 55℃ Ambient Temperature | |||||
ROS-38A | 100 / 5A | 4.0 | 4.0 | 0.3 B-0.2 | 38 mm | 6.5 kg |
ROS-66A | 150 / 5A | 4.0 | 4.0 | 0.3 B-0.1 | 66 mm | 5.0 kg |
200 / 5A | 4.0 | 4.0 | 0.3 B-0.5 | |||
250 / 5A | 4.0 | 4.0 | 0.3 B-0.5 | |||
ROS-78A | 300 / 5A | 4.0 | 2.9 | 0.3 B-0.5 | 78 mm | 4.0 kg |
400 / 5A | 4.0 | 2.9 | 0.3 B-0.5 | |||
500 / 5A | 3.0 | 2.4 | 0.3 B-0.5 | |||
600 / 5A 800 / 5A | 2.0 | 1.8 | 0.3 B-0.5 | |||
2.0 | 1.5 | 0.3 B-0.5 |
ERCT Specifications
Model | Current |
| Accuracy & Burden (IEEE) | Window | Approx. |
ROS-66A | 150 / 5A | 1% ~ 150% | 0.3 B-0.1 | 66 mm | 5.0 kg |
200 / 5A | 1% ~ 150% | 0.3 B-0.5 | |||
250 / 5A | 1% ~ 150% | 0.3 B-0.5 | |||
ROS-78A | 300 / 5A | 1% ~ 150% | 0.3 B-0.5 | 78 mm | 4.0 kg |
400 / 5A | 1% ~ 150% | 0.3 B-0.5 | |||
500 / 5A | 1% ~ 150% | 0.3 B-0.5 | |||
600 / 5A | 1% ~ 150% | 0.3 B-0.5 | |||
800 / 5A | 1% ~ 150% | 0.3 B-0.5 |
Available Models
ROS-38A, ROS-66A, ROS-78A
- Download Materials
Low-Voltage Current Transformers or Extended Range Current Transformers (ERCT), ROS-A Series
Easy-to-print document, containing product description, specifications, and a selection table.
【Product Dimensions】Low-Voltage Current Transformers or Extended Range Current Transformers (ERCT), ROS-A Series
Download PDF for basic drawing(s) and dimensions of this product. For more detailed information, please contact CIC.
CT & PT Selection Guide: How to Choose a Current Transformer or Potential Transformer
How to select, based on application and power system attributes, the primary and secondary currents, burden, accuracy, rated frequency, type (indoor vs. outdoor), insulation material, etc.
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