What frequency range does CISPR-25 cover?

CISPR-25 covers frequency ranges from 150 kHz to 2.5 GHz for conducted emissions and 30 MHz to 2.5 GHz for radiated emissions, with specific limits for different vehicle classes and receiver protection.

How does CISPR-25 apply to motorcycle key systems?

CISPR-25 applies to motorcycle key systems by setting emission limits for electronic components, immobilizers, and control units to ensure they don't interfere with on-board radio receivers and communication systems.

What are the key measurement methods?

Key measurement methods include conducted emission testing using LISN, radiated emission testing in anechoic chambers, stripline testing for components, and bulk current injection for immunity testing.

CISPR-25 EMC Standards for Automotive Radio Disturbance Characteristics

Q: What is CISPR-25?

CISPR-25 is an international standard that specifies limits and methods of measurement for radio disturbance characteristics of vehicles, boats, and internal combustion engines to protect on-board receivers from electromagnetic interference.

International standard specifying limits and methods of measurement for radio disturbance characteristics of vehicles, boats, and internal combustion engines to protect on-board receivers from electromagnetic interference, including motorcycle key systems and electronic components.

Standard Overview

Publication Date

2021 (Latest Edition)

Status

International Standard (CISPR)

Application

Automotive EMC Testing

Frequency Range

150 kHz to 2.5 GHz

Emission Limits and Test Methods

Conducted Emissions

150 kHz to 108 MHz

Voltage disturbances conducted on power supply lines

Class 3: 84-74 dBμV (150 kHz-30 MHz)
Class 4: 74-64 dBμV (150 kHz-30 MHz)
Class 5: 64-54 dBμV (150 kHz-30 MHz)

Radiated Emissions

30 MHz to 2.5 GHz

Electromagnetic field strength at specified distances

Class 3: 54-44 dBμV/m (30-108 MHz)
Class 4: 44-34 dBμV/m (30-108 MHz)
Class 5: 34-24 dBμV/m (30-108 MHz)

Component Testing

Stripline and TEM Cell

Testing methods for individual components and sub-assemblies

Stripline method: 1 MHz - 400 MHz
TEM cell method: 30 MHz - 1 GHz
Absorber lined shielded enclosure

Vehicle Testing

Complete Vehicle EMC

Full vehicle testing in anechoic chamber or open area

Anechoic chamber testing
Open area test site (OATS)
Absorber lined shielded enclosure

Motorcycle Applications

Key System EMC

Specific requirements for motorcycle electronic systems

Immobilizer system emissions
Key fob transmitter compliance
ECU electromagnetic compatibility

Immunity Testing

Bulk Current Injection

Immunity testing methods for automotive components

BCI method: 1 MHz - 400 MHz
Current levels: 1-200 mA
Substitution method validation

Implementation Features

Test Equipment Requirements

Essential test equipment and setup requirements for CISPR-25 compliance testing.

EMI test receivers with CISPR 16 compliance
Line Impedance Stabilization Network (LISN)
Anechoic chambers with specified dimensions
Stripline test fixtures for component testing
TEM cells for radiated emission testing
Bulk current injection probes and equipment

Classification System

CISPR-25 classification system for different vehicle types and protection levels.

Class 1: AM radio protection (150 kHz - 30 MHz)
Class 2: FM radio protection (30 MHz - 108 MHz)
Class 3: Mobile services protection (30 MHz - 1 GHz)
Class 4: Enhanced protection for sensitive receivers
Class 5: Maximum protection for premium vehicles
Frequency-dependent limits for each class

Design Guidelines

Best practices for designing automotive systems to meet CISPR-25 requirements.

PCB layout optimization for EMC performance
Proper grounding and shielding strategies
Filter design for conducted emission reduction
Cable routing and harness design
Component selection for EMC compliance
System-level EMC design considerations