Instruction Idea: Timed Input

[deep6ixed]

Been doing some upgrades to our equipment and programs around the shop to some our older equipment, installing the Do-More and analog in the old 205 racks.  Found a few situations around our equipment where we are using timers simply to check that an input has been on long enough to toggle something else.

One of our machines has a flapper that moves back and forth as wire runs across it.  If there is a tie up the flapper moves forward and stays there, but if there isn't a tie up the input goes swings high and low as the flapper moves.  So we have to have that input feed a timer, then if the timer completes its preset then shut the machine down.

The idea I have is, Timed Inputs:

Input On Delay:  The input must be high for a preset time before it is considered high by the ladder code.
Input Off Delay: The input must be low for a preset time before it is considered low by the ladder code.

I'm not sure if it's possible, or other people would consider it useful, but it's my two cents.

[BobO]

I see the benefit. You could view it as a specialized ON/OFF delay timer or it could be an input filter box. Not sure which would be more straightforward.

[plcnut]

I could see something like this being useful if placed in TopOfScan. If the option was instruction based (versus configuration based) then I could even use a bit to enable/disable the 'filter'.

[ATU]

I vote for input filtering accessible by a system structure.

[BobO]

I vote for input filtering accessible by a system structure.

Which would be highly useful for the built in inputs of a brick. Not so much for the 350th input associated with a Ethernet remote base.

And you need to smart about the way you use image register, too. Runtime access is nice, but does it need to burn critical image register when a setup instruction can get there as well?

[ATU]

Agreed

[LWgreys]

Hummm! I think i mentioned something alone this line a little while back call Signal debounce. I have to use timers to control the state of the inputs from sensors due to the movement of material packets pass the sensors which have small gaps between the material.