General guidelines

The following guidelines should be observed regarding the power supply:

  • A surge limiter must be installed at the junction where the flex enters the building.

  • Disturbances to the mains power are dampened by industrial line filters installed at the entrance to the system.

  • Sensitive devices are protected by surge limiters and surge arresters at the input feed.

  • Transformers can also be used as filters. For high frequency disturbances the transformer must be equipped with single, or preferably double, shielding.

Example: Solution for the power supply

The following illustration shows an example of filtering the mains power by using a double isolated transformer:

NOTE: A good ground connection is vital when installing transformers. The transformer housing must be bolted to a conductive earth plane.

Guidelines for partitioning in the system

The power supplies for the individual devices should be wired as point-to-point from the line entry:

Separate power supplies must be provided if extremely sensitive and high interference devices are used concurrently in the same power supply system:

Devices with high inference capabilities must be connected as close as possible to the line entry and sensitive devices connected at a distance from the line entry: