Size marking on the case is the bare core dimension (OD × ID × H), not the cased or finished size.
Nanocrystalline toroidal core 100×80×20 mm
100×80×20 mm nanocrystalline toroidal core, Black PBT Class B 130C.
Soft-published ahead of stock. Expected availability October 20, 2026. The image is a dimension diagram; product photos will be added when inventory arrives.
CCNT-100-080-020-HFBK is a 100×80×20 mm nanocrystalline toroidal core for large-cable ground-fault CTs, busbar metering CTs, and industrial residual-current monitoring. Its nanocrystalline HF characteristic suits higher-frequency magnetics where size, window, and permeability must stay in balance. Choose this size when cable or busbar clearance and magnetic area come first.
Arriving October 20, 2026
$81.721 piece
This SKU is soft-published for selection and SEO. Product photos will be added when stock arrives. Request a quote now, or join the waitlist for an in-stock notice.
Technical Specifications
Bare core dimensions
Cased / finished dimensions
Magnetic properties
Finish and handling
Environmental
Applications and selection
Applications
- large-cable ground-fault CTs
- busbar metering CTs
- industrial residual-current monitoring
- utility-scale current sensing
- large-cable/busbar ground-fault protection CTs
- utility-scale revenue metering CTs
- industrial residual-current monitoring transformers
- switchgear/panel current-sensing cores
When to choose this size
This 100×80×20 mm toroidal core is sized for large-cable ground-fault CTs and related designs in the nearby size family. Step down to the 90×60×20 mm core when board space, enclosure height, or a tighter footprint matters more than winding room. Move up to the 105×75×30 mm core when you need a larger outer diameter, winding window, or higher throughput than this part can comfortably support. In short, pick CCNT-100-080-020-HFBK when your design for large-cable ground-fault CTs fits this window and OD; pick a neighbor when compactness or power handling shifts the trade-off.
Winding notes
Magnetic calculations should use the bare 100×80×20 mm geometry (Ae 1.67 cm², Le 28.2 cm). The winding must fit the finished window: cased ID is 75.8 mm, not the 80 mm bare ID. Keep the winding distributed around the toroid to limit leakage and local heating. High permeability (μi 80,000) supports useful magnetizing inductance at practical turn counts; stay within 1.25 Tesla saturation and the -40°C to +130°C PBT Class B 130C limit.
Related application guides
Frequently asked questions
Are stated dimensions bare or cased?
The 100×80×20 mm size marked on the case is the bare core (OD × ID × H). Finished cased size is 104.5 × 75.8 × 23.4 mm. Use bare dimensions with Ae and Le for magnetic design, and the finished inner diameter for winding clearance.
Is this core suitable for a current transformer?
Yes. It is a nanocrystalline core sized for large-cable ground-fault CTs, including large-cable/busbar ground-fault protection CTs. High permeability helps you reach useful secondary inductance with practical turns in a 100 mm OD.
When should I choose a different size instead?
Choose the 105×75×30 mm core when you need more winding window, heavier wire, or higher throughput. Choose the 90×60×20 mm core when board space or a smaller footprint matters more than this 100×80×20 mm envelope.
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Get pricing, availability, and winding support for CCNT-100-080-020-HFBK.