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Posts posted by kratmel

  1. Hi,

    1)Please check HW-config in Visilogic

    2) From manual ---- Connecting RG Pins. For correct operation of digital and analog inputs and for EMIimmunity, connect the RG pin of all the expansion modules containing RG signals to the adapter module 0V signal. The overall length of the wire connecting the RG pins to the adapter 0V signal must be less than 3 meters. Connect the RG pins inseries (daisy chain). To facilitate this, use both the RG pins.

    3) From manual----Do not connect the neutral or line signal of the 110/220VAC to the device’s 0V pin.

    4) Use another power supply.


    If no success - please build only one module configuration with EX-A2X and check module separately on table.


  2. As far as I understand the author of the topic - he was going to create a system that collects data on the operating time of the plungers.
    He does not need to control them - but only count the time of the on state.

    To do this, he was going to connect the output signals of the existing in the system controller to the inputs of the samba PLC.
    If so, then his actions are clear and correct.

    Accordingly, Ausman emphasizes that if the Samba PLC controls the process - then the connection of its own inputs to its own outputs is redundant and can be replaced by a simple program reading of the state of the outputs.

    That is, the 1-st question to the author, what he wants to do:
    - only to record operating time and to inform when service is necessary;
    - manage the installation and record the operating time and notify when maintenance is required;
    - add to the system options that were not implemented by the existing controller;

    -other option ....?

    Second - if present controler used for control plunger - what controller used? What type of output connection used- PNP, NPN, DESCREAT, PWM, ANALOG?  

    3-rd -  Why I10, I11 used?

    This information needed for understand which solution is most suitable for his system

    12 hours ago, neil76 said:

    I was planning on taking  +24V input from our machine controller interface and connecting  to I10 or I11 to initiate the counter on the samba system, is this possible.


  3. Thanks,

    This is foto  of installation for elevator -  NEMA 4 cabinet with two VFD inside working now on 3 production lines. The first of them was installed 2 years ago.


    The customer had problems with the wires. Shielded remote control wires and cables to two motors are damaged very quickly (galvanic chemical production).

    And this often led to the failure of VFDs that were mounted in a large control cabinet at the beginning of the line.

    We changed the scheme - put two VFD in the NEMA 4 cabinet and installed it directly on the elevator. Currently, only a flexible mobile unshielded power line is used to supply power to the cabinet. If the power line breaks down - this is not a problem.

    Relay galvanic isolation with separate power supplies was also used to control the VFD discrete inputs.
    This protects the frequency converters in the event that the remote control accidentally enters to the bath with live electrolyte.

  4. 13 minutes ago, Joe Tauser said:

    part number mentioned above is not in the table

    It is little copy paste  mistake in table   :)  0007 is not 1.5kW drive (row#6).

    I use the rule 1 to 8, respectively, 1 volume of the frequency converter should correspond to 8 volumes of air in the box where the VFD is placed in a closed cabinet. It works on an elevator that moves over chemical baths. However, there the ratio of operating time to the total time of the VFD cycle there does not exceed 40%.

    P.S. I cannot upload picture of this installation (my profile attachment limit if full) :(

  5. Hi  Ausman, in this case i found many different  solution on real machines.

    As for me no earth contact on power supply is MW idea for cost saving.  Now i see both variant of MW PS - old MDR with EARTH  and new without.

    Old wariant is approx 10-15% bigger price.

    But I think the grounding (or not present gronding) of the primary side doesn't matter if the power supply has a grounded minus of the secondary part.


    Maybe you can find useful this link.


    start from p.1-17.


    In this document is presented OV connection to the ground with waveforms:




  6. Hi Skof,

    Stepper motor by definition - an open loop control system.
    After switching it on, it must be set to a known position. (Homing process)
    You probably think it will be able to stay where it left off.

    However, this is only possible if the driver controls it by natural characteristics (magnetic step). That is, the 200-step/rotation motor must be electrically rotated only for 200 steps/rotation.

    If you use a driver with step divider(from 2 to 128 or more) - after shutting it down, it will forget electrically divided step where it was (and motor will rotate a little by himself to the magnetic step position) - and there will be an offset that you will not be able to take into account . You can test it...

    Therefore, either you have to go to the zero position (home sensor) every time you turn it on, or sooner or later there will be a moment when the engine breaks the valve.

    Another way - make that the motor could not break the shaft mechanically (make mechanical stops), or electrically - put limit switches.

    Can you post hardware setup (motor, driver, valve) foto?

  7. 1 hour ago, Skof said:

    But If I cant get a hold of the position of the valve, there is a problem. If the motor keeps turning it will break the valve.. 

    Maybe my post will not help solve the problem with stepper motor,

    but I want to note (you wrote about the possibility of breaking the valve) - this system, even with the best settings, will break it someday ...


    Therefore, I recommend abandoning the stepper motor and consider other options:

    1) use the 3 state control actuator  with analog feedback (Belimo or other type), and apply the control algorithm idea described in the example

    V120_PID_motorized_valve_output_with_physical_feedback.vlp  from Visilogic help.

    2) use the 3 state drive without feedback but with the ability to safely stop at the end points and not break even with a constant control signal.

    An example PID with motorized valve.U90  is present in the U90ladder software  program.  You can use idea from this code.

    3) use actuator with analog input

    3) use actuator with networking future and control it via Unistream.

  8. On 3/1/2020 at 3:51 AM, kratmel said:

    It's a pity, we have only 12 months on Earth

    I thought that there were not enough months on earth.

    On 3/1/2020 at 7:02 AM, Ausman said:

    there was an unfortunate problem with it

    In fact, if you look at a welding machine from a well-known manufacturer, you can guess why it stopped working.

    The time machine told her to make this leap, cancel the license and stop work. However, the license was indefinite and therefore on the second attempt it changed the number of months in the year ..


    I had to overcome this shift in time - the welding machine works.

    However, evidence of the time machine remained on photo. 😎

  9. 12 hours ago, Isakovic said:

    Is it recommended or not to use different power supplies for main power and output power? If both are referenced to ground I guess not, but what if they are floating?


    Use different  power supply possible only when output  is "isolated". Fof example V200-18-E3XB  has 2 isolated pnp/npn (source/sink) transistor outputs and  4 isolated analog outputs.  However, the user must remember that these separate power supplies must be turned on and off at the same time or in the correct sequence. As an option - start powering the panel and then power the output - and turn it off in reverse order.

    12 hours ago, Isakovic said:

    I remember a case when I had safety circuit cut +VO line as a bonus security on Jazz unit. This rebooted PLC when activated so I don't use it anymore. Why was this happening? It was the same supply for PLC and outputs.

    The PLC uses output drivers that are protected against short circuits, overheating and usually undervoltage.
    Turning off the driver power (in your case + V0) could trigger one of these protections - and accordingly cause the PLC to restart.
    It's just a theory - I don't have a Jazz panel with transistor outputs to investigate your case.

    Therefore, a second CONCLUSION should be made - the user cannot use separate power supply for solid-state outputs of the PLC, unless the instructions indicate that they are isolated.


    • Like 1
  10. Hi,

    I will try to describe why it works without a connection.
    1) There is  output board inIside of the Unitronics OPLC controller.
    2) Each of the solid state outputs is a part (one channel) of the few  chip VN340SP (or something like that on foto).

    3) To send signals from the processor to this chip, we must have one common wire and several separate ones for the required number of outputs. This common wire also neded for power the VN340SP.  This wire is the OV contact you specified.
    4) This OV contact is connected to the main power OV contact of the PLC panel through a small fuse (you can check with a measuring device that the resistance between the 0V and 0V contacts is not equal to 0 Ohm).  For example i post foto of little fuse and 0V power connection for SAMBA SM70 board.



    That is why you output operate with  0V not connected.

    5) If you neglect to connect this contact, it may happen that the fuse (or another cirquit) inside PLC blows and all your outputs stop working.
    Conclusion - always use the connection RECOMMENDED by the manufacturer.
    This will save your controller from problems and save you money.

    • Like 2
  11. Please find in Unitronics U90 ladder Help sample project:

    C:\Program Files\Unitronics\Unitronics U90 Ladder\Examples\PID\On off with hysteresis.U90 and open it.

    Please "Save as" this project with New name. In HW Configuration section of project change controller type to JZ20-UA24. Open this controller configuration.

    Please configure analog input Type (proper termocoupler type must be used) and select MI0 - destination for Analog input.


    Download project to PLC and use O0 to control the heater (you must use properly connected  SSR or contactor for power control).

    Read JAZZ JZ20-UA24 hardware configuration manual for connect TC on p.5


    Post result and quastion in this topic.

  12. Is it possible that present this  issue from help?

    ----Be aware that:

    A Data Table and the Struct it is linked to cannot have identical names.

    If the names are identical, you will not be able to link the struct members to the parameters of Data Table ladder functions.---

  13. As i see in help - WatchDog timer duration = 500 milliseconds.

    If in project present long DTI with row  from 0 to N (i do not know what number N  is long???)  insert row to 1, 2, 3.... (small number) row make a lot of shift row operation... to N+1

    If this operation is to long in time (program "stopped" in point  "insert row" ) WatchDog is activated.

  14. Everyone in the process of building a program in the Visilogic comes to their own style of writing.
    Therefore, we can come to the same action in our programs in completely different ways.

    In most cases, I have to test the program without having the whole system at hand.

    Therefore, for almost all types of panels, I wrote "my standard" routines for polling inputs and output control.
    This led to the idea that the activation of the output should be only in one place in the program - in this case, the subroutine OUTPUTS.
    Input polling is similar in another subroutine INPUTS.
    Values from inputs are overwritten into variables and used later in the program code. In this case i can add tesing MB for manual activation of input via online simulation.
    Each subroutine generates its own variable which should activate the output in the OUTPUTS subroutine only when the desired screen is active or the required condition is met.
    It is especially useful to see that the output is turned off by an emergency button or subroutine in one place.



    • Like 1
  15. I support the  version that this is a problem with updating Windows.

    However, I had problems with the USB to COM driver once due to interference from the computer's power supply.
    It was powered from a different power  than the machine to which it was connected.

    Disconnecting the power supply from the mains and running on batteries solved the problem in this case.

    Now i use isolated USB to COM.

  16. 6 hours ago, Pavel M said:

    Hello, so i tried to organize PWM on my output and put it on my digital input

    Please use hardware PWM out O0 or O1 configuration for test. Please delete PWM scan block from ladder. Using software PWM method gives incorrect results for your case.

    Maybe ladder PWM generation is interrupted by immediate command.


    Hardware PWM do not use CPU resorces for generation.


    2 hours ago, Flex727 said:

    Your V200-18-V3XB _HAS_ high-speed inputs.

    It is used for shaft encoder in author project...  :(

  17. I don't know, maybe  it will help ...
    I would advise the author to turn his PLC into a test bench for a while.

    Set a high-speed output (O0 or O1) with PWM function in the configuration and make it possible to change the parameters (Duty Cycle and Frequency)  of this output on the screen.  Also start-stop buton on screen and PWM run bit ladder logic needed. You can build automatic frequency increment with fixed step from 0 to the 1000Hz for example.

    Use wires to send a signal from this output to the input that the author wants to turn into a counter.

    Step 3 - Write the counter code with an interrupt with the result displayed on the screen and setup RESET button.

    Add a standard high-speed input to the configuration. Connect it to the same PWM output via wire.

    5- step

    Add a code that will count the pulses via HSC and show their number on the screen (also frequency is possible to mesure via hardware HSI). RESET button needed also.

    Reset both counters, start the output at the specified frequency and duty cycle or use automatic frequency increment .

    Next, see at  the frequency and check  when the counter with an interrupt will not have time to count. It can be evaluated by stop output when  INTcount not equal HSCcount

    Make some investigation with duty cycle parameter change also.


    The last step - disconnect simulated by PLC signal and connect real signal.  Take a few different tests.

    It is interesting to see the results in this topic.
    Unfortunately, I do not have such a 18E3/4XB module at hand for experiments.



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