In industrial environments where there will inevitably be a substantial amount of electrical noise, disturbance and unintentional electromagnetic induction, the questions we need to ask are, ‘Can the Raspberry Pi cope with EMI? Will my prototype achieve acceptable EMC?’
What sources of EMI are present?
Industrial environments are often loud, but it’s the silent noise – the electronic disturbance – that can damage the performance of sensors and communications systems or stop them from functioning altogether. The two main types of EMI are conducted and radiated. Conducted electromagnetic interference is caused by conductors coming into direct contact; electromagnetic noise is passed through cables from the emitting device to the susceptible device.
Radiated interference is when electromagnetic waves are transmitted wirelessly without the physical contact of conductors. With radiated waves, disturbances are not confined to the surface of the conductor – rather, disturbances will radiate away from it. One type of radiated EMI is near-field interference – capacitive and inductive coupling between two circuits.
Read the full article in the April issue of DPA.