Why can't a Programmable Controller or Programmable Terminal be used for the safety circuit?
The IEC 60204-1 (JIS B 9960-1) standard specifies that a safety circuit cannot be made using a programmable controller alone. This comes from the general requirement of the same standard that safety related functions must be constructed from proven circuit technology and parts. If the circuit relies on the operation of programmable electronic devices, this requirement may not be satisfied.
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Compact (104.5 mm), lightweight (1.3 kg) and easy-to-install Safety Laser Scanner
Supports ISO 13849-1 (PLe/Safety Category 4). Can be used on higher risk level applications by connecting to Safety Controllers.