Some frequency-dependant components in electronic hardware can produce electric, magnetic or electromagnetic fields. If these fields are strong enough, they can interfere with other apparatus and cause undesired effects. Electromagnetic Compatibility (EMC) is the ability of electrical equipment to operate without being effected by or causing Electromagnetic Interferance (EMI).
The EC introduced directive 89/336/EEC in 1989 which defines the EMC criteria within which all electric equipment marketed in the EU must operate. The original concept was to equalise trade in Europe and keep the Customer informed (bias was against cheap imports with no filters that could disturb other control equipment). Not all manufacturers Sales teams take much notice of this and no firm has ever been prosecuted, as far as the author is aware.
Although the legal onus is on the manufacturer and their authorised representatives to advise the customer to use the correctly filtered equipment, it is up to the user to select equipment with First or Second environment compliant filtering to suit their application; First Environment covers use where the supply is shared with residential loads - Second Environment covers non residential loads.
It is more important to use motor wires that are screened, armoured or completely encased in metal conduit. This reduces the leakage of EMI and offers a conductive path back to the Inverter (required for EMC compliance in any case).
The Parker SSD Drives products we sell up to 7.5kW all include EMC Filters to the First and Second environment, as long as they have '-F-' in the product code. Most of the others include Second Environment filters, unless they say otherwise.
If you have an earth leakage protection system on the supply to an Inverter with First Environment filters, it will trip. Some of the filter caps are connected to earth and make a pulse of current when the power is turned on. The solution is to use a supply without an Earth Leakage Circuit Breaker (ELCB) as long as this is safe for you, buy Inverters with Second environment filters as long as the leakage level is compatible with the ELCB or buy Inverters with no EMC Filter at all.
Not all ELCBs are compatible with the use of Inverters.