In this chapter, let's learn about the functions of the safety programmable controller.

• 2.1 What is "dual input discrepancy detection"?
• 2.2 What is "input dark test"?
• 2.3 Precautions on Programming for the Safety System　　
• 2.4 Wiring Methods for Safety Devices　
• 2.5 Safety Communications　
• 2.6 Summary