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EMC

GB/T 18387-2017 Magnetic Field Limits

Radiated Emission (RE-H) – Magnetic Field Strength Limits (0.15 MHz to 30 MHz)

Magnetic field radiated emission limits for electric and hybrid vehicles per Chinese national standard GB/T 18387-2017, covering frequency range 0.15 MHz to 30 MHz. This standard applies to the measurement of electromagnetic radiated emission from electric and hybrid vehicles.

Limit Visualization Curve
Levels in dB(µA/m). Formula: f is frequency in MHz.
Frequency Range MHz
Peak Limit [dB(µA/m)]
0.15 to 4.77 37.36-20 lg(f)
4.77 to 15.92 64.52-60 lg(f)
15.92 to 20 16.45-20 lg(f)
20 to 30 -9.57

About GB/T 18387-2017

GB/T 18387-2017 specifies the limits and measurement methods of electromagnetic radiated emissions (both electric and magnetic field) from electric vehicles and hybrid electric vehicles in the frequency range of 0.15 MHz to 30 MHz.

It is equivalent to standard SAE J551-5. It is designed to protect off-vehicle receivers from electromagnetic disturbances produced by electric powertrains, traction batteries, and other high-voltage vehicle systems.

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How to read the GB/T 18387 magnetic-field reference

User task

Use this page for the magnetic-field branch of GB/T 18387-2017 for electric and hybrid vehicles. It keeps the 60 cm electrostatically shielded loop arrangement and dBµA/m result distinct from the electric-field page.

Choose before comparing

Confirm the magnetic-field method and 3 m measurement distance before comparing a row. The reference uses dBµA/m, a 60 cm shielded loop, 9 kHz receiver bandwidth, 5 kHz maximum step and 10 ms minimum dwell; Annex A is a 10 m conversion context.

What the displayed rows mean

Field type and antenna
RE-H is magnetic field strength in dBµA/m with the prescribed 60 cm electrostatically shielded loop; it is not the electric-field dBµV/m branch.
Distance and receiver
The displayed test geometry is 3 m with 9 kHz RBW, 5 kHz maximum step and 10 ms minimum dwell.
Annex conversion
Annex A supplies the 10 m reference conversion context. It does not make electric-field and magnetic-field results interchangeable.

Common misread

The shared 3 m and receiver settings do not make RE-E and RE-H the same measurement. Keep the field type, antenna, unit, receiver conditions and Annex A conversion context together.

Reference boundary

EMCCalc uses the National Standards Information Public Service Platform record for GB/T 18387-2017 and summarizes the encoded magnetic-field rows. The current standard and complete vehicle test method remain authoritative; no certification decision is made here.

Content review date:

Source and verification

Primary source

National Standards Information Public Service Platform — GB/T 18387-2017 Clauses 5–8, Table 3 and Annex A: field limits, site, receiver, antenna and distance conditions

Applicability
Electric and hybrid vehicles; this page is for magnetic-field strength, not electric-field strength.
Read this limit with
  • 0.15–30 MHz
  • Magnetic field strength
  • 3 m measurement distance; Annex A documents the 10 m reference conversion
  • Peak detector; 9 kHz receiver bandwidth; 5 kHz maximum step; 10 ms minimum dwell
  • dBµA/m; f in MHz for the displayed formulas
  • ALSE or OTS and the prescribed 60 cm electrostatically shielded loop-antenna arrangement
Last source-link and context review
Verification method
The source link, edition/section locator, and measurement context were reviewed against the values shown here. This reference is not a formal conformity assessment or certification.

Engineering reading

This is a magnetic-field limit. Do not substitute it for the electric-field page; use the geometry and receiver conditions required by the cited standard.