Electromagnetic immunity is the condition that an electrical or electronic device, equipment or system can operate without degradation in an environment with electromagnetic disturbance. It is important to remember that all electronic devices are affected by electromagnetic disturbances. Electromagnetic compatibility (EMC) has therefore become so important. However, no device or system is immune to electromagnetic waves. So EMC problems will always exist.
There are three ways to solve the electromagnetic interference problem:
- The electromagnetic surge in the source must be eliminated or reduced (low noise design, decoupling or shielding)
- Electromagnetic interference paths (air or conductors) should be eliminated or attenuated (screening, reorienting, filtering, separation)
- Increased immunity of the affected device or system (high immunity design, screening, filtering, decoupling)
Elevators and escalators are also electrical devices, and electromagnetic compatibility problems also apply to these devices. The control panels of elevators and escalators can transmit unwanted signs (interference by conductivity), as well as spreading signs on the air as an antenna (interference by radiation). Cables of different sizes in a circuit or system sometimes act as antennas. Cables can therefore act as both electrical and magnetic interference sources. The two basic elements of cable performance are the quality of the shielding material and the cable screen grounding. In the meantime, shielding means electromagnetic isolation of cables.
In the elevator and escalator panels, power cables and communication cables should be laid as far as possible in separate channels. However, due to lack of space, these cables are sent together in the same channel. This can always cause electromagnetic disturbances. In order to prevent this, it is recommended to keep the power cables and communication cables as far away from each other as possible and to install shielded analog cables which are more resistant to electromagnetic compatibility (EMC).
Another application method is to create a Faraday Cage with the grounding of the cabinet cupboard cover in order to prevent electromagnetic interference to the system from the elevator and escalator control panels. This cage reduces the electromagnetic effects that may occur from the panel to the outside or from the outside to the panel.
In short, elevators and escalators in high frequency areas must meet the electromagnetic compatibility criteria and standards.