11.03
2 General Information about Integrated Safety Systems
2.1 Drives and CNC controls with integrated safety
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
2-25
2.1 Drives and CNC controls with integrated safety
"...For the protection of persons from hazardous motion, safety measures must
be implemented on machines. They are intended to prevent hazardous
machine motion while the protective devices are open. These functions include
monitoring positions, e.g. final positions, monitoring velocities and standstill, or
stopping in hazardous situations.
For the technical implementation of safety measures up until now, mainly
external equipment and devices have been used. These include contactors,
switches, cams, and monitoring devices. If a hazardous situation is detected,
these devices generally initiate a contact switching operation in the power
circuit thus causing the motion to stop (Fig. 2-1).
With the integration of safety functions, drive systems and CNC controls
perform safety functions in addition to their functional tasks. Very short
response times can be achieved because of the short data paths from
acquisition of the safety-relevant information, e.g. speed or position, to
evaluation. The systems with integrated safety technology generally respond
very quickly when the permissible limit values are violated, e.g. position and
velocity limit values. They can be of decisive importance for the required
monitoring result. The integrated safety technology can directly access the
power semiconductors in the drive controller without the use of
electromechanical switching devices in the power circuit. This helps reduce the
susceptibility to faults - and integration also reduces cabling..."
M
Integrated
safety
technology
CNC
Drive
control
External safety
technology
M
External safety
technology
Drive
control
EXT_INT.DSF
Fig. 2-1
External safety technology, integrated switching technology
(taken from /6/)
Extract from /6/