Preparing your device for an EMC measurement

A device behaves differently in each operating state. Decide in advance which states matter for the measurement.

• Typical continuous operation and full load
• Start-up, switching and control processes
• Communication active or inactive
• States in which anomalies have already occurred

Cables and connected equipment often influence the result more than the circuit board itself.

• All cables used in the field, in realistic lengths
• Power supplies, sensors and actuators as in operation
• Substitute or load resistors where real loads cannot be transported
• A note on which lines are shielded and how the shields are bonded

Check in advance whether the supply you need is available at the site in question.

• Operating voltage and current draw during the measurement
• DC or AC, single-phase or three-phase
• Special requirements such as inrush currents or start-up behaviour
• Details of fuses, plugs and the type of connection

The more that is known about the setup, the faster an anomaly can be narrowed down.

• Block diagram or schematic, an extract is fine
• Layout or stack-up of the board, if available
• A short functional description and the operating steps
• Known anomalies and results from earlier measurements

So that changes are possible during the measurement without dismantling the whole setup.

• The enclosure can be opened and closed without special tools
• Access to connectors, test points and controls
• Spare parts for changes to the setup, such as filters or ferrites
• Weight and dimensions for transport and setup