H2-ctrio

Its been awhile, thanks Phill for replying to me personally.

Ok, this thing is driving me nuts. I've used it to drive a high speed stepper motor which worked beautifully.

Now, I have a quad 240 ppr encoder wired to A,B,C,and M, channel 1. When we run the machine past 500 rpm, it does not measure accurately. So hey, lets use the pulse catch feature, my God who wrote that mess in the manual? LOL.

All I want to do is make sure my total count which is in V2000 currently stays accurate with increases in speed. I don't mind doing the math, and I don't want an output to follow it, but it seems like that is what I have to do, and then put that output in a memory location, and use that instead of V2000. And I can only enable pulse catch on terminal D, and it just sort of doesn't seem to do anything, lol.

HELP!

Johnny Master Electrician
[email protected]

Actually 500rpm is 8.3rps, so 8.3 * 240 is 1992hz.

I will double check my scan time, and give more info.

Thanks.

My scan time is about 6ms give or take. As the manual says, a pulse that lasts less than 1ms is typically hard to catch during the CPU scan.

So use this wonderful feature called 'pulse catch'. Its so wonderful I hate it, lol. Going to try a few things.

Thanks Bryan for your reply.

Johnny

Maths was never my strong point, out by a factor of 60 isn't too bad for me.

High speed counter inputs should work outside the program cycle time, if you have used them as standard inputs you will have a problem. What I would expect to happen it that you will have a special High Speed Counter instruction. Then you could interrogate the High Speed Counter each program cycle, but more normally you create an Interrupt either based on time or pulses received. So go back and check your program, what kind of counter have you used? I have no direct experience of the module or make of PLC but High Speed Counters are High Speed Counters no matter what system they are based in.

Its actually called an 'H2-CTRIO' high speed counter module.
The high speed pulsed output works great lol.

Its not the program that is the issue, its getting this stupid module to retain the high speed count with 'pulse catch' until the CPU can see it.

I will figure it out, what a silly modulue.

Thanks again.

If is a High Speed Counter module then 'pulse catch' is the wrong way to go and probably won't work. You must use a High Speed Counter instruction to read data from a High Speed Counter module. Pulse catch is generally only used to catch pulses that are too quick to be detected inside your program cycle time, high speed counters work independently of the cycle time and so pulse catch doesn't apply. What kind of counter have you used???

http://www.plcs.net/chapters/count15.htm

The module is made by Host Engineering. They should be able to help. Perhaps you need an Annex board shown here.

I hear what you are saying, think I'm close.

I think my temp linkage was loose, it works fine.

Sorry and thanks.

Johnny

Actually, that module works very well. I thought I was throwing raw pulses to the cpu, but the mod converts it by whatever factor you choose before, so scan and pulse width don't have to be an issue. It does all the counting/velocity calc's for you as well. Through that into a memory address and use it in your program. Just have to pulse an infrared system based on velocity and I've got a working machine!

Its nice to be back!