Posted to News on 11th Nov 2011, 23:44
Drives with safety functions - Machinery Directive implications
Gambica has published a technical document, entitled Status of safety-related variable speed drives in regard to the EC Machinery Directive 2006/42/EC, to provide clarity for drives manufacturers and suppliers, as well as machine builders and system integrators.
The position paper starts by explaining the background, in that 'safety components' are covered by the Machinery Directive in the same way as machines. Three classes of variable-speed drive are then discussed:
- Drives with integral safety functions
- Drives without safety functions but with optional safety modules
- Drives with integral safety functions and optional safety modules
There is also a section that discusses terminology, with reference to 'power drive system' (PDS), 'power drive system with safety-related function' (PDS (SR)) and 'basic drive module' (BDR) - which is a term used in EN 61800-5-2 (IEC 61800-5-2) to refer to an adjustable speed electrical power drive or variable-speed drive.
Safety components
Gambica's experts have concluded that, as far as the Machinery Directive is concerned, drives with safety functions should be treated as safety components, as should safety modules; in the case of a drive with integral safety functions and a module for additional safety functions, both should be treated as safety components.
A detailed explanation of the argument behind this is provided within the paper, together with information about how to treat drives that also perform safety-related logic functions.
Follow the link to download a copy of the position paper, Status of safety-related variable speed drives in regard to the EC Machinery Directive 2006/42/EC (320kB PDF).
