Because the law changes to machinery safety, such as the design philosophy is needed to get a secure system. I recently put in a training course on safety PLC and was initially shocked by the fact that we are outside the traditional techniques. Over the years I've been in the design and operation of many security systems, some good some not so involved.
So what will the new law for people like me think, first of all, forget the lock-wired? Yes, that's all you knowhave simply forgotten. This was a bit 'to get to the sink, but if you think about it, you can begin to see the benefits - Fault tolerance, before we had a lot of cables and complex circuits to add to achieve fault tolerance and in most cases error did not recognize, would need a weekly / monthly safety control device from a reset is not guaranteed. How many times these checks out?
Programmable Logic Controller
The introduction of a security check, we can pass the control andnote the results!
Wiring, in designing a circuit that I would always tie each emergency button to the main camp of the MCC, this has often been criticized for the cost of installation and wiring, but at least the coach would be a starting point, trying to diagnose problems on a safety circuit. Often, though this is not the case and a plant I worked on recently had 60 E-Stop imagining all paused series thread on this track. With the safety PLC is not a problem as more remoteInputs and outputs provide coded pulses can prevent cross-channel and fault diagnosis is fed directly to the PLC, which is no longer transmitted aux wiring of security will now be the feedback.
So they are sold? Yes, I think, and hopefully with the correct application can be implemented more robust system that not only protect the plant more reliable, but the people. My only concern now is to convince a customer.
Safety PLCprogrammable logic controller