DIY Stepper function

[mrhappyzapp]

Hello shooter.

I have thought of the DIY encoder. Your idea has merit. Could I not get away with just one prox switch to get a signal off the shaft. Micro switches can wear due to their mechanical nature.

Now the thing is I can program a count-up/down scenario but once again what happens when the power outage happens. I am having difficulty with that part of programming so as to get the trolley to home out and then go back to it's previous position to continue the sequence.

I will not be around to push the home button and reset the sequence. Must be done automatically.

Would I need to set a register for the counts and should this be the case will the register retain the value so the trolley, once homed will read this register and "goto" the position to continue rest of sequence?

Thank,
mrhappyzapp

 

[keithkyll]

One prox, not microswitch for DIY encoder.
PLC writes values to memory during last microseconds of power fail. You select which ones. Use special contact SC2 to detect power fail. It's active for one scan when power returns.

 

[mrhappyzapp]

Hello keithkyll.

When you say "special contact SC2", which controller do you speak of or is this the same across all controllers?

Thanks,
mrhappyzapp

 

[keithkyll]

SC2 is for the Click. It's called "First Scan".
Other PLC's have special relays with similar functions.
First Scan, .1 second, 1 second, etc.