Technical Knowledge
Straight answers on core parameters — loss, permeability, air gaps, annealing — plus selection guides for transformers, CTs, meters, EMI filters and welders.
Specification Q&A
Core loss: what it is and how to specify it
Core loss (W/kg) drives transformer temperature and efficiency. Learn what determines it and how to specify a target.
Read more →Permeability (µi, µmax): reading the datasheet
Initial and maximum permeability decide sensitivity, phase error and inductance. Here is how to read them.
Read more →Air gaps: why cut cores hold inductance under load
A controlled gap stores energy and stabilises inductance against DC bias and temperature.
Read more →Tolerances, coating and insulation
What ±0.1 mm means, and how coating thickness affects winding and withstand voltage.
Read more →Why annealing after cutting matters
Cutting introduces stress that raises loss and lowers permeability. Annealing restores both.
Read more →Saturation flux density and DC bias
How much DC your core can take before inductance collapses — and how to choose material.
Read more →Silicon steel vs nanocrystalline vs ferrite vs amorphous: which core material?
A practical comparison of the four common core materials by frequency, loss, saturation and cost.
Read more →Transformer core types explained: laminated, wound, cut and 3-phase
How the main transformer core constructions differ in loss, noise, cost and manufacturing.
Read more →How to size a transformer core: turns, area and flux
The working formulas for core area, turns and flux density, with a worked example.
Read more →Application Guides
Choosing a core for distribution transformers
Silicon steel wound cores vs amorphous: loss, noise, cost and manufacturing.
Read more →Instrument transformer cores: nanocrystalline or silicon steel?
Accuracy class, phase error and size trade-offs for CT/VT cores.
Read more →Residual current device cores
High initial permeability keeps trip thresholds stable across temperature.
Read more →Cores for smart meters and energy metering
Small toroids with tight tolerance for class 0.5S/0.2S metering.
Read more →Common-mode choke core selection
Nanocrystalline vs MnZn vs NiZn for EMI suppression.
Read more →Cores for inverter welders
Lighter transformers, higher duty cycle, lower temperature rise.
Read more →What is a toroidal core? Advantages, types and how to choose
A toroidal core is a ring-shaped magnetic core wound from strip steel or tape. Learn why it is efficient, where it is used, and how to specify one.
Read more →Current transformer cores: accuracy classes, burden and core choice
How CT accuracy class, burden and saturation drive core material and size.
Read more →Request a quote or sample
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