Need assistance creating a program

Hi Group,


I have a EZ-420 PLC and part of a program and I am trying to create a complete program for an E-Stop test bench. I have just enough knowledge to be dangerous (well maybe not even that much) and am trying to scale a 0-10V signal for the EMP brake. I have been up and down the EZ Automation forums and the info I have found has only confused me more which has lead me here and to the following question: is there anyone that has knowledge of the EZ brand of PLC'S and might be willing to help steer me in the right direction? Thank you in advance for your time and have a great day!


Sincerely,
Cliff Turnell

Welcome to the forum.

in order for us to help you, please post the following information.
your understanding of what you need to do.
what have you done so far? show your work.

james

Hi James,


Thank you for the clarification on how this group operates, I look forward to working with and learning from you all. The test bench I am trying to resurrect is a Marathon electric 3 phase AC motor/Warner clutch-brake "combo" driving a gearhead (our OEM product). In Between the motor and gearhead we have a Adantex FRAT 350 EMP brake (thru bore). the motor is being controlled by an Automation Direct GS1 VFD (VFD is using 0-10V setting). The ultimate objective for me is to create a program that does the following:
1. ramp motor up to 3000 RPM in a "clockwise" direction in 7 seconds.
2. have motor dwell at "target rpm" for 15 seconds.
3. engage clutch and apply brake voltage (0-10V) to stop shaft in .1 sec (effectively an E-Stop).
4. have system sit idle for 60 seconds to allow brake to cool.
5. start sequence again with motor shaft going in "counter clockwise" direction.
6. this would be 1 cycle.


I currently have a partial program that I found while going through the paperwork (attached) that allows the machine to ramp up, dwell and stop but it does not talk nice with the HMI (by that I mean "configurable" settings in the HMI (RPM/dwell time/ramp time) are not being recognized by the PLC even though the addresses appear to jive). At this point I would be happy just understanding how to scale the analog signals get the brake to stop quickly but ultimately I want to create a program that is configurable via the HMI to meet my needs. Sorry for the diatribe but I just want to be a clear as possible about my goals up front. Thank you and the rest of the group in advance for your time and if I did not attach the files properly please let me know. I have plenty of supporting documentation as well if needed.



View attachment e-stop program_Page_1.jpg

View attachment e-stop program_Page_2.jpg

View attachment e-stop program_Page_3.jpg

View attachment e-stop program_Page_4.jpg

View attachment e-stop program_Page_5.jpg

I'm no expert by any means, but let's talk mechanics first.

you have the following

motor ---- brake --------- gearhead

the motor is 3,000 rpm.
you have an analog brake

what is the gearhead?
what gear ratio?
what is it driving and what is the torque?


james

Hi James,



The gear head is a 10:1 planetary (Nema size 23). It is driving an "inertia wheel" . The torque created by the motor is 71 IN-LB and subsequently 710 IN-LB out of the gear head. When the brake is applied in an E-Stop fashion the reflected load is absorbed by the gear head in an attempt to find out how many times the pinion gear can take the "shock load" before failure. I have attached a few pics of the bench to help provide an idea of the setup (the cabinet is a little crowded but once everything is running properly it will be re-done to provide room to work). If you need any further clarification or pics or need to contact me directly just let me know. Again, thank you in advance for your time.


Regards,
Cliff

I am unable to see the pictures.

several things to consider
1. if there is no load on the gear box, that is one test.
2. You need to add a load on the gear box, and run the test, you want real
world situations.
3. with a load on the end of the gear box, you MUST, MUST make sure the
support structure, fastening bolts to the load, gearbox, brake, and motor
can stand the sudden stop.
4. you MUST have a protective wall (not mesh) to protect you during the test.
I have seen to many test parts fly apart during testing.
5. replace all bolts after every test due to stress & fatigue.

james

I guess I should provide a little more back story. This test bench has been fully vetted and was running properly approximately 5 years ago, when the brake wore out it was "mothballed". The gentlemen that originally built and programmed it is no longer with the company. The "working" program was lost when he left and I am now trying to take a partial program and complete it as my programming skills are not strong enough to build a new one from scratch yet. In my earlier reply I should have said that "the reflected load of the inertia wheel that is mounted to the gearhead output shaft is absorbed by the gearhead" thus creating the shock load. I am not sure why the attachments are not coming through, they are all jpegs. I have tried to attach again, hopefully it works. I see that I can put the pics in the body of this reply but they are hard to view.

It appears that the PDF files are opening, I will try to send a few more...

This is the partial program that I am trying to work with...

So I was able to get the brake to react the way it should (and also have the ability to send various amounts of current) by changing "Opr2" on line 15 of rung 1 from "brake interval" to a constant so that when the result is called on line 1 of rung 6 the value is now numerical and can be scaled against the 14 bit IO module. Now if I can just figure out how to call the register locations of the HMI and convert them to times in the program, would a "drum" instruction possibly work for this?