Electromagnetic interference

Definition

Electromagnetic interference (EMI) refers to the disruption of the normal operation of electronic devices caused by electromagnetic radiation emitted from external sources. It can significantly affect the performance of data acquisition systems, leading to inaccuracies in data collection and processing. Understanding EMI is crucial in designing robust systems that ensure data integrity and reliable operation.

5 Must Know Facts For Your Next Test

1. EMI can originate from both natural sources, like lightning, and man-made sources, such as motors and radio transmitters.
2. There are two main types of EMI: conducted interference, which travels along power lines or signal cables, and radiated interference, which spreads through the air.
3. Data acquisition systems must be designed with proper filtering techniques to mitigate the impact of EMI on measurements.
4. Shielding is often employed in the design of sensitive equipment to prevent EMI from disrupting signal integrity.
5. Regulatory standards exist to limit EMI emissions and ensure compatibility among electronic devices, helping to maintain performance in environments with multiple technologies.

Review Questions

• How does electromagnetic interference affect the performance of data acquisition systems?
  • Electromagnetic interference can cause data acquisition systems to produce inaccurate readings or disrupt the collection process altogether. This interference can distort signals, leading to errors in measurement and analysis. To ensure reliable operation, engineers must design these systems with effective EMI mitigation strategies, such as proper grounding and shielding techniques.
• What are the differences between conducted and radiated electromagnetic interference, and how do they impact data collection?
  • Conducted electromagnetic interference occurs when unwanted signals travel along wires or cables, while radiated electromagnetic interference spreads through the air. Both types can severely impact data collection by introducing noise into the system. Conducted interference might affect the power supply or data lines directly, whereas radiated interference could disrupt wireless communication or sensor readings from a distance.
• Evaluate the importance of electromagnetic compatibility in the design of integrated data acquisition systems.
  • Electromagnetic compatibility is vital in ensuring that integrated data acquisition systems operate effectively without causing or experiencing disruptive interference. Designers must consider how different components will interact within an environment filled with other electronic devices. By addressing EMI during the design phase—using techniques like shielding and filtering—engineers can create systems that maintain high performance and reliability while minimizing disruptions caused by external electromagnetic fields.

Related terms

Electromagnetic Compatibility: The ability of electronic devices to operate without interference with one another, ensuring that they can function correctly in shared environments.

Signal Integrity:

The measure of the quality and strength of an electrical signal as it travels through a system, which can be affected by EMI.

Shielding: The use of materials or designs to block or reduce electromagnetic interference from affecting electronic components.