Use of Electrical Equipment of Machines

in Accordance with DIN EN 60204-1 (VDE 0113-1):2007-06 in Industrial Premises with Potential Fire Hazard in Accordance with DIN VDE 0100-482 (VDE 0100-482):2003-06 
Statement of the DKE/K 225 and the DKE/UK 221.2

1. Legal stipulations in the EEA Area

To satisfy the requirements of the EC Machinery Directive (98/37/EC), the standard EN 60204-1 “Safety of Machinery – Electrical Equipment of Machines - Part 1: General Requirements for Electrical Equipment on Machines” listed in the Official Journal of the EU plays a crucial role. Within its scope for the standards user this standard safeguards the presumption of conformity with the requirements of the EC Machinery Directive described in Appendix ZZ of the standard.

Furthermore, observance of the Electromagnetic Compatibility (EMC) is also given and is referred to in the DIN EN 60204-1 (VDE 0113-1):2007-06 “Safety of Machinery - Electrical Equipment of Machines – Part 1: General Requirements (IEC 60204-1:2005, modified)” of the German version of EN 60204-1:2006, see there 4.4.2 and 8.2.8 if the EMC standards stated in 4.4.2 are observed. In general the basic standards listed below the EMC Directive are to be considered with regard to observance of the latter, as they include state-of-the-art.

2. Normative Requirements

The series DIN VDE 0100 (VDE 0100) (German implementations of the HD 384 or HD 60364) applies to electrical installations which are a fixed component of buildings. Electrical equipment used in them is described only as far as its selection and use in the installation are concerned.

The electrical equipment of machines which is covered by the standard DIN EN 60204-1 (VDE 0113-1):2007-06 begins at the mains connection point of the electrical equipment of the machine.

Stipulations from the series DIN VDE 0100 (VDE 0100) do not apply in principle to the electrical equipment of machines in accordance with DIN EN 60204-1 (VDE 0113-1):2007-06.

3. Fire Protection Aspects from the Point of View of the Series DIN VDE 0100 (VDE 0100)

The requirements of the DIN VDE 0100-482 (VDE 0100-482):2003-06 (corresponds to HD 384.4.482 S1:1997 + Corrigendum 1:1997) “Erection of Low-Voltage Installations - Part 4: Protective Measures – Chapter 48: Selection of Protective Measures; Section 482: Fire Protection for Particular Risks or Hazards” are important if industrial premises are to be categorised as “industrial premises with a particular fire risk – industrial premises with potential fire hazard”. In Germany the directive VdS 2033 “Industrial premises with potential fire hazard and risks to be equated with these” includes corresponding case studies. Consequently, for example, building areas within pressrooms, such as the reel paper storage, as well as sawmills can be included among the areas with potential fire hazard.

4. Description of Problem

State-of-the-art is that most of the electric drives used in machines are designed as frequency closed-loop-controlled or open-loop-controlled drives utilising semi-conductor technology. If these drives are used without EMC measures (filter technology, shielded cables, etc.), system perturbations and EMC faults would occur due to the steep switching edges. Commercially available drive modules therefore usually feature these EMC measures.

As the speed-controlled drives utilise semi-conductor technology and require EMC measures, the current load of the protective conductor increases significantly on account of protective conductor currents (leakage currents). A significant proportion of these operational leakage currents is caused by parasitic capacities, e.g. in shielded motor cables.

The standard DIN VDE 0100-482 (VDE 0100-482):2003-06 stipulates that, in order to protect cable and line installations in the event of insulation faults, TN and TT systems should feature

• residual-current-operated protective devices (RCDs) at a rated residual current I_ΔN ≤ 300 mA or alternatively
• circuit breakers incorporating residual current protection (CBRs) in accordance with DIN EN 60947-2 (VDE 0660 Part 101), Appendix B, which disconnect external conductors and neutral conductors from the power supply; or
• residual current monitors (RCMs) in accordance with DIN EN 62020 (VDE 0663), independent of mains voltage with switching devices, e.g. power switch

The leakage currents described previously may cause these protective devices to trip, even though there is no insulation fault.

Moreover, in accordance with the product standard, residual-current-operated protective devices (RCDs) are limited to 125 A rated currents.

If circuits in machines have a significant level of leakage currents as mentioned above, the use of the aforementioned protective devices with standard measures are not practical from a technical and economical point of view.

The measure “Inherently earth-fault-proof wiring and inherently short-circuit-proof wiring in accordance with DIN VDE 0100-520 (VDE 0100-520):2003-06, 521.13” mentioned in this standard as an alternative to these protective devices is not required within a machine of this type and may not be applicable.

5. Suggested Procedure

If the combination of a residual-current-operated protective device (RCD) particularly with one or more electronic devices in the electrical equipment of the machine is incompatible and this is confirmed in writing by the manufacturer of the machine, e.g. if the total leakage current is too high for the reasons mentioned above or the type of fault currents impair the function of the residual-current-operated protective device, the following measure can be selected as an alternative to the use of the protective devices mentioned above:

In the electrical installation of the building up to the mains connection point of the respective machine the wiring shall be inherently earth-fault-proof and inherently short-circuit-proof (in accordance with DIN VDE 0100-520 (VDE 0100-520)).

On the machine side, starting from the mains connection point, the electrical equipment of a machine must be designed according to the requirements of DIN EN 60204-1 (VDE 0113-1).

If a machine is used in industrial premises with potential fire hazard, additional measures may be required, dependent on the risk assessment in accordance with DIN EN 60204-1 (VDE 0113-1):2007-06, 4.1.

DIN VDE 0100-410 (VDE 0100-410) refers to the conventional prospective touch voltage limit.