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marke

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Everything posted by marke

  1. Any genuine success stories about Best Energy? All looks vaguely familiar! https://www.best.energy/
  2. marke

    Welcome to Pages

    Welcome to Pages! Pages extends your site with custom content management designed especially for communities. Create brand new sections of your community using features like blocks, databases and articles, pulling in data from other areas of your community. Create custom pages in your community using our drag'n'drop, WYSIWYG editor. Build blocks that pull in all kinds of data from throughout your community to create dynamic pages, or use one of the ready-made widgets we include with the Invision Community. View our Pages documentation
  3. uSD cards are slowly increasing in size and that is causing issues with some equipment where the uSD card is used to store data. Older XLe OCS units were limited to 2GB cards as a maximum size, and even then not all cards would work. Later firmware enabled access to data on some cards up to 16GB, but most 16GB cards can not be read. With a new card, it always pays to format the card in the XLe to ensure compatibility. You may need to try a number of different card types to find a compatible card and stock up on spares of cards that work. Sizes are increasing and while some batches work, others may not.
  4. The IEC 6-1131 programming languages cover a wide range of programming skills. Instruction List (IL) is a legacy language from early days of PLC programming and is probably the least used language of the suite today. Ladder Diagram (LD) and Function Block Diagram (FBD) are both graphical programming languages designed to provide a familiar environment for electricians who are used to assembling relay logic circuits, perhaps using additional function blocks such as timers and counters. For pure logic sections of the project, these can provide a simple program to write and to follow, but when the logic moves away from simple contacts and coils, or basic function blocks, the languages become quite clumsy but still workable. Scripted Text (ST) is a "plain language" programming language that handles data processing, analog values and mathematical functionality in what can be essentially a self documenting program listing. The text format and syntax is very similar to Pascal with similarities to C, C# Python and similar languages. Computer programmers adapt to ST programming very quickly. Instruction List is the most basic of the languages and probably the least intuitive. It is essentially the "assembly language" programming of PLCs. -Expect higher programming frustration and reduced readibility from the use of the Instruction List language. It is probably a reasonable way to mask IP and functionality. Sequential Function Chart (SFC) is perhaps one of the most powerful tools to use in the IEC language suite. I prefer to consider SFC as a multi-dimensional State Machine than a language, providing an environment and tool set that enhances a well structured program design, debugging and ease of augmentation. Brake the program design into a series of States and rules to move between the states, then program that in SFC. Code can then be added to each state in either ST or LD. Some Steps (States) can be written in LD while others are in ST. It is not necessary to focus on one language only. Which language should I use? that is entirely up to the programmer. Use which ever language performs your task the best. While you can only use one language within a code module, you can use multiple modues and different languages in the modules. For pure relay logic, consider LD. For visual Function block programming, consider FBD and for numeric processing, it is hard to go past ST. There is not right and Wrong, if it works for you, then it is right for you.
  5. LMPForum has just been upgraded to the latest version available. This has been enabled following the transfer to a more modern server with up to date server software. There should be performance enhancements and possible fine tuning over the next few weeks. Best regards,'Mark
  6. The Danfoss MCD500 series soft starters have reached end of life and they have ceased production, to be replaced by the Danfoss MCD600.
  7. Over the years since the release of the EMX3, we have experienced increasing problems of installation trips due to bad harmonic voltages. Severe harmonic currents on weaker networks, primarily due to the major increase in usage of VFDs in industry has resulted in increasing levels of voltage distortion and that voltage distortion, if it is bad enough, can disturb the synchronisation of the SCR control circuits to the supply voltage zero crossings. The phase modulation of the voltage reference causes the installation trip. This is just one of the consequences of rising harmonic voltages on the supply.
  8. Active filters are now becoming rather commonplace, but they are not all equal. Small filters can have compromised DC Bus capacitors that are not designed for long life, or easy replacement. Some of these filters are failing at around five years of usage, and operation in a very high impedance supply with a lot of harmonic voltages, can lead to excessive heat and premature failure. - pay half the price for half the life and poor servicability!! Best regards, Mark.
  9. marke

    Webinars

    Follow the weekly webinars with Chuck and Casey and all the previous webinars on YouTube. https://www.youtube.com/user/HornerAPG/videos?view=0&sort=dd&shelf_id=0
  10. marke

    Cscape 9.9 Sp5

    CScape 9.9 SP5 has been released. This is a minor update and there is no real need to update.
  11. Please ensure that the “Use Classic Cscape Mode” is unticked in the Tools | Applications Settings screen. You can then tick the “Support IEC Editor” and “Support Variable Based Ladder Programs” at the bottom of the Application Settings under Supported Program Types. If the “Use Classic Cscape Mode” is ticked, the other two editor modes are greyed out and can not be selected.
  12. Horner have released and Android APP called HORNER FABRIC and it is available on the Google Store for a small fee. This app requires that you have a registration with the Horner Automation website at https://hornerautomation.com/and it uses the same login details as does the latest release of CScape, 9.9 service pack 4. For full details on how to use the app, watch the youtube video at
  13. The LMPForum.com website has been moved from it's old server to a new, modern server with upto date software. This should overcome some of the issues with posting and very slow response. - I hope!! Any issues, PM me and I will look into it..
  14. Horner have released CScape 9.9 SP4. Horner CScape 9.9 Service Pack 4 provides a major upgrade to the IEC functionality of CScape. This release adds ON Line programming and line by line debugging. The full benefit of Service pack 4 requires upgrading the controller firmware to 15.50 or later.
  15. Horner have released an interim service pack for CScape 9.9 CScape 9.9 SP3.5 is now available for download from the HornerAutomation website. The major enhancement is adding a couple of drivers for new devices.
  16. The Electrical Calculations Software is not currently being supported. Hackers released hacked passwords to this software making it economically un-viable to invest in any further development. The last release is not compatible with Windows 10. A major rewrite and time investment is required to update to current windows releases and there are no plans or justification for doing this in the near future.
  17. The issue of mandating screened cables with VFDs is an interesting one and it is not strictly correct in that it is possible to minimise the spread of common mode switching currents without the use of a screened cable, but there must be an alternative low impedance return path for the capacitive currents flowing from the motor windings to the motor frame, back to the source of the PWM waveform, the DC Bus of the VFD. Background : The VFD converts incoming AC voltage to DC and charges a bank of DC Bus capacitors.The DC is then chopped up by two series AC switches across the DC Bus with the junction of the AC switches connected to the phase output terminal.A sinewave current is synthesised by modulating the action of the two switches using PWM techniques. There are essentially three instantanious states, output connected to DC Bus Positive, output connected to DC Bus negative and DC Bus disconnected.Modern VFDs use IGBTs or MOS FETs as switching elements and these can switch in less than 100 nano Seconds. - Very fast opening and closing.The Output voltage is essentially a PWM modulated waveform switching between the positive DC Bus and the Negative DC bus, so with a 400 volt motor, this waveform is rapidly switching from +300Volt to - 300 volts. In the motor, there is capacitance between the motor windings and the motor frame.The switched voltage waveform is applied to the motor windings and this results in a high charging and discharging current to flow from the motor windings to the motor frame through the parasitic capacitance between the motor windings and the motor frame.The charging and discharging currents flow at the operation of each switch (there are six switches in a three phase inverter).The current transients are very short and high in amplitude. - High frequency components when analized on the frequency domain.If the frame of the motor is not bonded to earth at all, the motor would be subjected to voltage impulses in sympathy with the charging currents, but the frame voltage would be swtiching between the DC bus polarities minus the leakage current through the other phases. The frame voltage will be pulsing at hundreds of volts.The capacitive current must find paths back to the DC bus and that can be via any equipment connected between earth and the incoming supply. To minimise the switching voltage on the frame of the motor, it is imperative to provide a very low impedance path back to the DC bus. This impedance must be low at the frequencies of the noise spectrum caused by the switching waveform and this is typically in the order of 150KHz. At 150KHz, skin effect is a very real problem with the current only flowing in the very outer surface of the conductor. To achieve a good return path that minimises the switching voltage on the frame of the motor, the earth return path back to the VFD must exhibit a large surface area over the whole length of the return path. A screened cable is a very effective means to provide that return path. At 150KHz, the impedance of the screen as a conductor is typically fifty times lower than the impedance of the internal earth conductor. This will reduce the voltage on the frame of the motor by a factor of fifty. Suitable alternatives are a steel pipe of a simliar diameter as the screened cable, a flat braid equal in width to the screen opened out, A copper, or aluminium, or steel strip 1.5mm thick with a width equal to or greater than the screen of the screened cable opened out. A screened cable is specified because is is an easy way to achieve the low impedance, high frequency return path, not because is actually blocks the conductors from radiating. Unfortunately, many "experts" believe that the screen is used to form a faraday cage rather than a low impedance return path for the switching currents. Many experts also claim that the screen must be terminated at one end only. This is true for control circuits, but definitely not VFD output circuits.
  18. VFD induced stray voltages can cause major issues in cow shed (dairy palours). Typical symptoms are : Interference with ear tag readersHigh Somatic Cell Count in the milkAgitated Cows - reluctance to enter the milking balesExtended milking times due to poor milk let downExcessive defecation while in the bailsHigh Mastitis incidence. There are some basic fundimental issues when using VFDs in dairy sheds that must be adhered to when using PWM VFDs : The connection between the VFD output and the motor MUST be using a screened cable with the screen continuous the whole way. The screen must be terminated in the output of the VFD by a circular clamp around the screen to the chassis of the VFD, or, if there are conatcors on the output of the VFD, the screen must be bonded to the metal gear tray the the VFD is mounted on by a circular clamp or saddle clamp. If there is an isolator on the output of the VFD, (typically mounted near the motor), the screen of the cable going to the VFD and the screen of the cable going to the motor must be bonded together by a circular clamp(s). This can be via a flat metal plate, or bonded together. The screen of the cable must be bonded to the motor. This can be by means of an EMC gland into the motor terminal box (assuming metal box) or via a clamp onto the frame of the motor. The EMC filter in the VFD must be enabled, or an external EMC must be fitted. Where these steps have been correctly taken, and a problem still exists, there are a number of steps that can be taken, but there must be a continuous screen path between the VFD chassis and the motor for these additional steps to work properly. Potential improvements : Add low frequency common mode chokes to the output cores going to the motor. This usually entails one or more turns of all the three phase conductors through one or more common cores. (NOTE: output conductors only, not the earth conductor). High inductance EMC ferrite cores can be used but the best results are from specialised cores designed for this purpose. - consult your VFD supplier. External EMC filter on the input. dv/dt filter on the output of the VFD Sinewave Filter on the output of the VFD. (use sinewave or dv/dt, but not both.)
  19. Recent updates to web browsers and security issues have made posting to this forum difficult. Microsoft explorer, Mozilla Firefox and Google Chrome do not save new posts reliably, but Opera still seems to work. I am working on determining the cause of this so that it can be rectified. Replies to existing posts still seems to work OK. Best regards, Mark.
  20. marke

    Webinars

    Horner have been running very good webinars on CScape and the Horner OCS units during May, June and July 2020. At present, these webinars can be viewed from the Horner website. See www.hornerautomation.com/webinars/ The next is on August 12 2020 on the topic of Ethernet IP Communications.
  21. marke

    Xle Updated

    The XLe has gone through two stages of update. The first update, was to include a mini USB programming port. This requires CScape 9.8 or later to connect. Earlier versions of CScape will not find this processor. The second update, is to enhance the processor performance and include an Ethernet port. This unit is known as the XLEe and will commonly be specified as an XLe 1E2 where the 'E' refers to the Ethernet port.
  22. The EMX4i range is being expanded to cover larger models. More information coming.
  23. Horner have released the much publicised CScape 9.9 SP3 This service pack is primarily aimed at the Advanced Relay logic programming environment with enhancements such as UDFBs, Gmail support for emails, downloadable protocol enable/disable, DHCP and DNS support, MQTT Sparkplug IOT support. Some of these additional functions will require a firmware update which is also available for all processors. Should you upgrade? If you have a program that works and does not reuire the additional enhancements, then leave it alone. If you are starting a new project and the enhancements are of value to you, or if you are using one of the newer processors, then you should upgrade. NOTE: while Horner endeavour to keep as much upwards compatbility as possible, there can be changes in some established functions in new versions of CScape that may require tweaks in the code. Avoid upgrading the CScape version of code that is running in the field without fully testing it first. You can have multiple copies of CScape on a single machine provided that they are installed in their own directory.
  24. EMX3 and EMX4 website See : www.aucom.nz
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