Kikis

Ηι, If you use a self-resetting timer you can get a resolution of 10 msec. This is 10 times faster than the SB7 pulse. You can find an example on the following link (old forum): http://www.unitronic...p?TOPIC_ID=2688

Do you guys ever thought about the idea of a portable handheld model that will support only local and remote I/O (No I/O on board)? There are applications where freedom of movement is required. An example is the following: http://en.kinco.cn/productById?kind=1&id=88 It would be great to see something like this in the future!

Joe, I'ts good to know that you have successfully tried this in the past. I think that is the best solution to the problem... Thanks!

Thanks again for the feedback. I was thinking of connecting a 2k/1w resistor in series with my PLC NPN output and connect it with the (-) pulse input terminal of the stepper drive. Then connect +24VDC directly to the (+) pulse terminal of the drive. The input is opto-isolated. Should it work this way or not?

Simon, thanks for your great support. Your post was really helpful for me. Please let me ask another question... What happens if i want to use a Jazz model to move one motor? Operating voltage of JZ 10-11-PT15 HSO is 20-28.8VDC.

Hi guys, I'm thinking of buying the following 3-axis stepper motor kit from ebay. http://www.ebay.com/itm/US-Free-ship-3-axis-425oz-in-Nema23-stepper-motor-112mm-matched-driver-CNC-Kit-/251235147807?pt=LH_DefaultDomain_0&hash=item3a7ec8201f I will not use the breakout board included in the kit but i wil use a Unitronics V350-35-TR34 instead. My application requires simple, not very accurate positioning of 3 axes. My questions are the following: The driver accepts pulses of 5VDC while the PLC HSO is 24VDC. How can i convert the high frequency pulse to 5VDC? Also the Pulses are NPN type. Is this a problem for the driver? Thanks in advance

Hello guys, I think that V570 model must also support the PTO function for up to 3 independent axis. There are applications where the 3.5" screen of V350 is quite small to fulfill the requirements. I think that a dedicated positioning expansion module for up to 3 axis would be the best solution. Hope to see something like that in the future. Kikis

I think that it would be great if Visilogic offered a ramp function for analog output. Just like the way we configure a filter for analog inputs. The user to enable/disable the ramp and link an MI for the ramp time from the hardware confuguration menu.

The ramp consists of 20 steps. I use a cycle time of 15ms (6*2.5ms)

Hi Nacho, I start a timer of 0.3 sec. I use the inverted contact of this timer as a condition to run PWM with 50% duty cycle. Then i use the Positive transition contact of PWM result MB in order to increment an MI and use it as the X value in a linear block.

I used PWM FB instead of a self -resetting timer. It is working as expected. Thanks for your support Joe! Kikis

Hi guys, What's the best way to have an analog 0-10V output with up and down ramp time? I want to have a ramp time of 0.3 sec for my signal. For example when i want to have 5V, instead of storing 511 (For 10-bit analog) immediately to the linked MI, i want the integer to be increasing gradually for 0.3 seconds and then to take it's final value. The same must happen when the MI is reset (From 5V to 0V). Thanks in advance, Kikis

Hi, Thanks for the reply. It is a little bit confusing because in PID configuration topic of help file it's written that: To enable PID, values must be provided for: Set Point Input Range:PV Low Limit & PV High Limit Output Range:CV Low Limit & CV High Limit These values are used to Auto-tune the loop. So i thought that as set point is used as a parameter to Auto-tune the loop,when it changes i have to run Auto-tune again.

Just got a new project, that requires among other, a heating zone control using 6 PID loops. When it comes to temperature control, I prefer to use external dedicated temperature controllers because I faced some problems with PLC outputs response (not Unitronics brand) in the past. However my customer wants everything to be controlled via HMI so I will use a V350 with IO-ATC8 expansion module and some digital I/O expansions. My application is as described below: 6 K-type thermocouple as input and 6 solid state relays for current switching. I will use PWM function block and Transistor outputs to “talk” to the SSR’s. I have set the cycle time to 1.5 second (Took the average of the recommended cycle time range that is given in PID tips topic in Unitronics help files) The SP value (set-point) for each loop is linked to a preset MI so that the user can change its value at any time from the HMI. My questions are the following: Do I have to run PID Autotune process every time the user changes the SP value? (Detect change in linked MI value). Do I have to write 6 different autotune codes for each loop? Thanks in advance, Kikis

Thanks again for the feedback. I have to say that the compiler and project optimizer are really helpful tools. It would be really great if Visilogic offered also a Project simulator that will run without connection to the PLC.

I've got another one question and i hope that someone here could help me. Project optimizer found some duplicate coils in my program. My application demands manual, semi-auto and auto mode operation. Therefore certain Outputs are used several times in different subroutines. These sub-routines are called conditionally and they are never running simultaneously as the machine can't be in auto and manual mode at the same time. What's the problem with dublicated coils? Thanks, kikis

Hi peter, My main mistake is that i was thinking that the PLC couldn't scan 2 or more sub-routines simultaneously. Now everything is clear for me. Thank you very much for your support. It really helped me!!

Hello friends, I have made a lot of projects using jazz and M90/M91 controllers. However this is the first time i will be using a vision series model and i'm not familiar with programming using sub-routines. I'm writing a program for a Vision 570 PLC which includes 3 different modules and 15 sub-routines totally. Even though my program jumps from one sub-routine to another, i would like to have a timer that will work continously without being affected by a sub-routine change. The timer's working time will depend on a user's preset value. Therefore it may stop working in the 3rd subroutine or in the 5th and so on. Is it correct to use an accumulated timer in every subroutine? So when it leaves a subroutine it stops working and when is entering the next one begins to decrement from the retained value. I also need to have a cycle counter where i used 0.1 second pulse and included the code in every sub-routine of the project. Is this correct? Thanks in advance, kikis