Description

The 80% NiFe Cores For Leakage Circuit Breakers may be provided in the form of toroidal or laminated form. The material for 80% NiFe Cores For Leakage Circuit Breakers is sensitive to stress after annealing and needs protection to prevent mechanical forces, It is provided by a plastic core or a suitable heat-resistant coating. Once Coated or boxed, the core is very strong, the main magnetic properties Highly linear and less dependent on temperature. In one aspect, the strip material limits the diversity of the shape of the mechanical core, but is limited The geometry of other hand-variable ring cores can be obtained at low processing costs. Of The current core size ranges from about 10 mm to more than 300 mm from the outside diameter. Basically, spaces or cut cores should also be available, however These options are not currently available as a standard on the market.

Features

  • High initial permeability, High output voltage, core size saving.
  • Low core loss, Good tolerance ability for large current impulse, Good protection of tripping of high current
  • High Curie temperature, Good temperature stability(-55℃~130℃)
  • Competitive price

Application

  • Electronic Leakage Circuit Breakers
  • Electromagnetic Leakage Circuit Breakers

Material Properties

Magnetic & Chemical Properties
Properties Measurement Unit 80% NiFe7
Permeability Permeability AC
Bs Tesla 0.751
Br Tesla 0.42
Hc 2(A.m)-1 Tesla 0.35
µ4 4 Tesla 550000
µ max Tesla 570000
Permeability AC
µ4z5 - 70000
µz86 - -
µmax - 95000
Core loss (W/Kg-1) 0.015
Chemical Composition
% Ni - 78%-81%
% Mo - 4.5%-6%
% Si - 0.05%-0.4%
% Mn - 0%-0.5%
% C - 0.01%
% Fe - Balance
Physical Properties
Density (g.cm -3) 8.7
Specific Heat (J.Kg-1.˚C-1) 460
Thermal conductivity W.m-1.˚C-1 19
Mean CTE between -50 & +200˚C ˚C-1 12.10-6
Electrical resistivity µΩ.cm 60
Curie Point ᵒC 420
Coefficient of magnetostriction at Saturation ∆l / l - 1-3 x 10-6
Melting temperature ᵒC 1450
Saturation Induction Tesla -
Hardness Hv 325
In Cold worked condition
UTS MPa 1050
0.2% PS(Cold Worked) MPa 1030
Elongation % min 3
In Annealed condition
Hardness Hv 160
UTS MPa 650
0.2% PS MPa 280
Elongation % 35
Grain Size - 8

KEY

  • Practical saturation measured for H = 800 A/m.
  • Remanent induction Br and coercive field Hc measured from H = 80 A/m.
  • Practical saturation Bs and Remanent induction Br measured for H = 800 A/m.
  • Measured for H = 4 mA/cm (peak value).
  • Sinusoidal excitation field H = 4 mA/cm (peak value).
  • Impedance permeability for B = 0.8 T.
  • Measurements made on 35X26X0.34 mm ring specimens after annealing in Pure & Dry Hydrogen for 4h at 1170°C followed by cooling at 200°C/h.
  • Practical saturation measured for H=5000A/m.
  • Core loss W/kg at 1.5T at 50Hz=3.90 max.
  • Typical operating frequency - 50 hz to 400hz

Product model and their tolerances

DIMENSIONS AND TOLERANCE
Outer Diameter (mm) Tolerance (mm) Inner Diameter (mm) Tolerance (mm) Height Tolerance (mm)
< 10 ± 0.4 < 10 ± 0.3 ± 0.3
< 25 ± 0.5 < 25 ± 0.4 ± 0.4
< 50 ± 1.0 < 50 ± 0.5 ± 0.5
< 80 ± 1.25 < 80 ± 0.75 ± 0.8
< 100 ± 1.5 < 100 ± 0.8 ± 0.8
< 160 ± 2.0 < 160 ± 1.3 ± 1.5
< 200 ± 2.5 < 200 ± 1.5 ± 1.5
< 320 ± 2.5 < 320 ± 2.0 ± 2.0
NOTE: General Cutting gap tolerance will be ± 0.5mm

Applications

Current measurement for:
  • Automotive
  • Aerospace
  • Medical
  • Renewable energy

Testing

As a standard practice PML checks Toroidal core (before cutting) for magnetic properties by tracing the B-H properties of the core itself. Below are results of a sample core

Sample Core Geometry
  • Outer Diameter - 160 mm+/-2mm
  • Inner Diameter - 110 mm+/-1mm
  • Height - 30 mm+0.2 /- 0.0 mm
GFCI Core Loop Plotter
Ind Pk(T) Permeability Loss/kg (Wt) H EffPk (A/cm) H RMS (A/cm) Ind RMS (T) Hc (A/cm) Br (T)
0.1 127150.24 0 0.0083 0.0059 0.0672 0.0019 0.02
0.2 144038.48 0 0.0134 0.0095 0.1378 0.0073 0.0868
0.3 158385.11 0 0.0188 0.0133 0.2102 0.0125 0.1708
0.4 164657.89 0 0.0242 0.0171 0.277 0.0166 0.2839
0.5 115868.36 0.0061 0.1674 0.1183 0.352 0.0204 0.3449
0.6 41492.51 0.015 0.3746 0.2649 0.4307 0.024 0.3815
0.636 14717.2 0.0183 0.4492 0.3176 0.4591 0.0253 0.3947