Is there something wrong with this SIS interlock design?
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As shown in the diagram, the emergency stop interlock is connected directly after the RS flip-flop. Will there be any problems with this in terms of logical operations? (For example, when the interlock is not activated, the RS flip-flop outputs 1; if the emergency stop button is pressed, then this circuit will have a signal of 0, one 1 and one 0. Is no logical operation required in such a case?)
The inverted outputs of the 2 emergency stop buttons are combined using an ‘or’ operation; the output of this ‘or gate’ is connected to the ‘or gate’ located before the R1S flip-flop.
Which design institute drew these plans without any verification or review? Regardless of whether the interlocking is correct or not. The graphic link is incorrect.
No problem. Connecting them together gives AND. The parking button comes first above everything else. Press to stop.
What was said on the 5th floor is correct; it reminds me that the emergency stop button and the action conditions I’ve used are placed in front of the OR gate. It should be done according to your diagram.
I was too simplistic. But with signed numbers, why isn’t it shown? Inverting the ESD button has the same effect as before; this logic does not reflect ESD priority.
The drawing isn’t detailed enough; in the actual configuration, an OR gate must be added, otherwise the wires won’t be connected
OR won’t work; the “1” output by RS is at the other input of OR, so AND is needed.
This post was last edited by hxch150804 on 2022-4-1 at 11:31. OP, you’re right – one person tells me to turn it on and another tells me to turn it off; whose instructions should I follow? This logic controller does not allow such coding; when you write the configuration in this way, it definitely will not compile. Unless the buttons are connected via hard wires to the control circuit of the solenoids – that is, if the two emergency stop buttons are connected in series to the power bus of the 6 solenoids, rather than being connected to the DI ports of the control system – then such a wiring scheme can barely be considered acceptable.