Direct PLC Dl05 controller with a 30 gpm flowmeter input

I need to know if a high speed input card will be sufficient enough to pickup up the flow in a metering line with a flowmeter and a 24vdc pulsed input.
Will it be accurate enough for repeatability or should i use a high speed counter card.
I will be using count instruction in the logic to get repeatability for the next each draw.
I am only familiar with AB rs500 and rs5000 software and am unsure what is the best route to take for direct plc?
Any examples of logic that could perform this function would be great.
Thanks,

What is the actual pulse rate?

The Pulse maximum rate would be 196 hz.
The fast input card is 2 milliseconds nominal for off to on signal and then 2 milliseconds from on to off signal.
The high speed counter card is 3 microseconds for off to on signal and then 3 microseconds from off to on signal.
I think I almost have top go with the highspeed counter card or I will be border line not getting my count pulse signal correct.
Once I measure the input pulse with a counter I will be using that count to shut off the next draw of flow meausurement.
Basically i will be calibrating a flow input pulse count then I will be measuring the output of the next flow with the saved calibration measurement.
This is so i can get a repeatability of what amount of fluid i want after the first calibration of flow measurement.

The other option if the PLC is a DC input model is to use the built in high speed IO. Take a look at Appendix E of the DL05 Manual. The build in high speed IO can go to 7kHz, IIRC.

Well we have decided to go with a DL06 series because of the larger expansion and 4 high speed inputs.
I have been very good at Allen Bradley plcs but I am not sure what to expect from direct plcs
If anyone knows the best place for a crash coarse In direct it would be very appreciated.
Thanks.

kickford1 said:

I have been very good at Allen Bradley plcs but I am not sure what to expect from direct plcs
If anyone knows the best place for a crash coarse In direct it would be very appreciated.
Thanks.

Click to expand...

Check out Bernie's AB to AD comparison web pages.
http://www.theplcguy.com/ABtoAD/Introduction.htm

He has links to some videos as well as several AB to AD comparisons.

High speed I/O setup for directsoft.

I am new to directsoft and automation direct and I need a good clear example of how to set up a high speed input for a flow meter on the first two inputs of this plc.
I have always used AB plc's and this is my first go around with direct.
I do not have the full programming software. Only the free version but i will soon be purchasing the full version because of a customers request.
I have been researching how to setup the v memory locations of the first two inputs and it is still not fully clear. I have downloaded too many pdf file.
A good programming example would be appreciated.
I will need to use the flow meter pulse to control a counter and then save it to a register so i can repeat the same amount of flow the next time.
Do I have to be online with the PLC in order to change the inputs to high speed via mode to 10?
Thanks

As shown in the examples for high speed counting, a rung triggered by the first pass (SP0) can write the values as shown to the various registers. Page E-16 of the online available (DL06) PDF shows a good example. From your description you won't need presets. V7633 will get the Mode 10 designation. The table on page E-14 details other V registers used for fine control of the X inputs.

Note that the Counter will be CT174 for input X0. This is technically an Up/Down counter (UDC) but you will be using it only in the UP direction using Mode 10. Also, remember that the accumulated count is in BCD. It spans 2 V registers and can get as high as 99999999. If your expected count will be above 9999 then you will have to use the box type double compare instructions rather than the convenient inline compares.

I'm not at wwork right now but let me know if I can help.

Thanks for all the help.
I believe this will get me going in the right direction.
I will keep you posted when I find out more about this project coming up.

One other question that I have is this PLC has a total of 4 high speed inputs. I will be needing a total of two fro two flow meters.
And I am under the impression that this is achievable.
What should be the counter number for X1 input on the second flow meter?
All the resetting of these counters will be done in the logic after the flow has stopped and the counts have been recorded to specific registers for a repeatable draw.
Thanks,

What should be the counter number for X1 input on the second flow meter?

Click to expand...

CT176 - see page E-15 in the manual.

Okay I am currently programming the fow meter controls and have had some success but my problem is this.
High speed counter is set to mode 10.
I am using the hi speed presets in the logic and if I use one preset I dont have a problem.
But i need to use two presets. One is ten percent of volume flow and one is finished flow.
I am using a LDD with a 10 percent V register copy of the flow recorded during a calibration and a full flow V register and that part works fine.
I am then using another LDD to put the copied v register into the OUTD register of V3640. This is to get a repeat of the original calibration.
After a counter reset and the counters accumulated amount reaches the calibration put into V3640 it will turn on special relay SP540 and this works fine.
But when I use 2 presets and write the next copy of calibration LDD to V3642 and turn on SP542 is where the problems occurs.
I am using a LDD Kfff to OUT V3644 to complete the presets being read.
The problem is if the first preset is made and not the second due to the cycle being interrupted.
Then CT174 counter is reset to zero.
The very next time I run the process it skips right over preset 1 and the SP540 bit then it reaches preset 2 it will enable SP541.
The next time I run the cycle with no interruptions it will enable SP540 at 10 percent and then SP541 when complete.
Do I need to write a LDD of 0 to OUTD V3640 and V3642 to reset the presets so I can reload them with my original calibration when I do not run a complete cycle or have an interruption.
Or should the presets reset from the beginning of counting every time?
Thanks,

I'm sorry that I can't help you in using presets with the counterss. I haven't done that.

Any other suggestions on coparing the calibrated counts of a particular counter as a double word and then controlling an output? I tried to use a greater than or equal to contact but it only allows me to go up to 9999 in that setting. I was doing a branched greater than or equal to for both the first word and the second word of the counter but that got to be too cumbersome. I thought the preset thing was the answer to my prayers. It works but it just doesnt like it when you dont finsh a filling cycle.
Thanks for the rsponse

You can use the CMPD instruction. It's a little less cumbersome.