2 General Information about Integrated Safety Systems
11.03
2.1 Drives and CNC controls with integrated safety
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2-26
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
2.1.1 Standards
and
Directives
"...The European Machinery Directive applies to all machines /1/. The minimum
requirements are defined in Appendix I of the Directive. These are defined
more precisely by the European harmonized standards. However, Standards
have not been drawn-up for all types of machines. For machine tools for metal
working, robots, and automatic manufacturing systems, some Draft Standards
and final Standards do exist (Table 2-1). In many cases, Category 3 acc. to
EN 954-1 is defined in these Standards for the safety-related controls. /4/
contains a comparison for implementation of various control categories
according to EN 954-1 using different technologies. The basic requirement of
this category is: Single-fault fail-safety with partial fault recognition.
As regards the electronics in general and electric drives in particular, EN 954-1
does not contain any special requirements. A working group of the German
Electrotechnical Commission has therefore drawn-up a position document that
describes the most important safety functions of electric drive systems in
machines and defined the requirements to implement the various Categories
according to EN 954-1 /2/. This position document is to be transformed into a
draft Standard..."
The description of the most important safety functions of electrical drive
systems in machines is contained in Chapter 4, "Function description".
"...The electrical drive system includes hardware and software components that
influence the movement of the machine. Possible components are e.g.:
electronic controls, closed-loop control components, drive motors, power and
data cables and parts. They can also be part of the CNC control..."
Table 2-1
Overview of safety-relevant controls in C Standards
EN
12417
Machining centers
EN 12415
Turning centers
EN 775
Industrial robots
Agreement button
Category 3
Category 3
Category 3
Speed reduction incl.
protection against
Category 3
Category 3
Category 3
unexpected start-up
(n=0)
Category B and
agreement button
Interlocking of
Category 3
Category 3
Category 3
protective devices
and equipment
Limitation of endstops -
-
Category 3
Emergency Stop
acc. to EN 60204
Category 3
Category 3
Extract from /6/