Did I Goof?

[ArikBY]

Hi

Could you please explain what is your application?
I will try to advice what better to use.Interupt,High speed counter
or Input refresh.

About input refresh just change the value for IR0 bit 0-7.
You can see the scan time in the bottom of your program in the right side.
then download your program to the PLC with seting(you just need to mark the box).
Feel free to ask more question if you need. we are here for that.

All the best.

 

[jonton]

Thankyou ArikBY,
A 1.5 meter long arm goes into a plastic Injection Moulding Machine to get the product. When the arm gets fully out we signal IMM to close and make more product. We could sinal IMM when we are half way out, and save some time, but I think we pass the half way magnetic reed switch 00.06 too quickly to see it. I went to the settings you showed and selected Input constant IR000 bits 05-06, and set time to 2ms. I wont know scan time till Monday. Does this mean inputs 00.05 and 00.06 are both fast inputs now? Or did I completely miss your point? How do I assign input 00.06 to an IR00003 to IR00006, or is it already IR00006. I understand to set time > scantime.
But I cannot read anything that tells how to associate input 00.06 with a IR0003 to IR0006, which will tell it to see faster.
Thanks again ArikBY and others, Regards
Jon T

 

[Jay Anthony]

OK... I've been watching this one for several days now and I thought ArikBY had you straightened out. I think he threw you astray when he posted the screen shot of the interrupt page of a CQM1H. Technically, he is correct. But your focused on the wrong section. Inputs 3,4,5,6 can be set for quick response which works fine with a very fast pulse which is shorter than scan. It is not good if you have a train of pulses with the frequency being more than one pulse per scan. Essentailly what the quick response input does is it makes a "pulse stretcher" so that a fast moving pulse is trapped and saved for the I/O refresh at the bottom of scan. It does not speed the program up because you are still limited by scan time but what it does do is make the pulse reliable.

If your intention is to shorten the response time from input to output, then this is a whole other story which will lead us off into interrupt subroutines. Give us feedback as to your real intention.

BTW,BobB, check your email.

 

[jonton]

Many thanks Jay,
Things becoming clearer all the time.
My intention is simply to see the pulse. Excecution can occur later. Its 500msec I will save, a scan time is not so big.
My book showed the section you pasted, called quick response operation, but not "setting quick response inputs" or "using quick response inputs"
So on the left of the settings page you posted, where it says interupt enable, I should not touch because I dont want to interupt.
I should search for DM6628, which will contain all zeros, and put a 1 in the 2 bit of ip6?
Have to go to work now, Monday a.m. here.
I'll return this afternoon.
Thanks heaps
JON T

 

[Jay Anthony]

If you use the settings page to set the interrupt enable to "Quick", then DM6628 will automatically be set correctly. Or you can set DM 6628 yourself. Be sure to cycle the power on the PLC for the settings to become active.

 

[jonton]

Yes Jay and thank you,
Since it was monday today, I rang local agent who was most apologetic once he realised he had not given me the info CD ver3.3 which BobB mentioned I should get free. Its in the mail.
Mean time he explained, since I dont need an interupt, to go straight to DM6628 BUT I MUST BE ONLINE or I dont see bits, then type 0010000000etc as you said.
Oh well, a little stress for me, Monday has gone, customer still happy, and PLCS.net makes the deadline.
So, SHOW ME TUESDAY
Bye for now and thanks to all,
Jon T