Showing posts from 2019

What is serial communication?

In order to understand communication protocols we first need to understand digital systems. A digital systems communicates a message in the form of binary information. This is a flow of digital pulses sent from one point to another creating a means of data transmission. Serial communication is a widely used medium to transfer information between various different equipment and peripherals. Data is in the form of sequential binary pulses. Binary can be represented in two states i.e: a one (1) represents a logic high or "on" status and a zero (0) represents a logic low or "off" status.  The different modes of transmitting data over serial communication Simplex transmission  is a one-way communications method, with only one client present on the network. if a sender engages in transmission then a receiver is only able to accept information. examples: Radio and television transmission.  Half Duplex mode  have both an active sender and a receiver, ho

ProfiHubs with diagnostic capabilities

Network downtime getting you down? Introducing PROCENTEC’s range of ProfiHubs , now with new diagnostic capabilities! The diagnostic ProfiHub is a versatile statistics / diagnostics logger that can be used to keep track of the overall network health and inform either the PLC or DCS of any network failures. These network failures could be in the form of repeated messages, illegal messages, missing ProfiHub terminations, live list changes or power supply problems. Audible or visible feedback can also be achieved by switching the integrated alarm relay of the ProfiHub . All ProfiHubs are now shipped with this functionality available as standard. Existing ProfiHub owners will soon be able to purchase upgrade packages to enable the diagnostic capabilities via a firmware update. The diagnostic capabilities are available for the B2+R , B5+R , D1 , B2FO2 , & B4FO2 and these hubs are fully compatible with PROCENTEC ComBricks providing you with a permanent monitoring sol

Anybus gateway's creating secure paths for IIOT solutions

Anybus has launched a new family of gateways built to boost your Industrial IoT development demands. These devices are designed to gain secure and easy access between equipment on all major industrial networks, transforming the way your industry, manufacturing business, process factory or packaging plant operates by improving visibility. Now you can establish a foundation for better performance by leveraging this data. The  Anybus IoT X-Gateways and Communicators  lets you seamlessly interconnect legacy devices and PLC control systems between industrial networks and OPC UA/MQTT. The information is controlled independently and your network remains secure and encrypted. How does it work? The Anybus IoT Communicator, still based on the tried and tested communicator development, will now enable users to integrate serial based RS232, RS485, Modbus RTU, DF1 and ASCII into an OPC UA or MQTT IoT data acquisition system.  Simply connect, configure and your done! Connect: M

PROFIBUS wiring error / B-line short

  PROFIBUS wiring error / B-line short IDX attended a PROFIBUS call out for a gold mine situated in Welkom. The client reported issues as “loss of communication and network trips”. Using the PROCENTEC Mercury Pro Kit (A complete diagnostics tool for troubleshooting PROFIBUS and Industrial Ethernet Networks) we were able to identify the underlying issue as a short between the B-core (red wire) and the PROFIBUS cable shield. The short in the PROFIBUS cable meant that the differential signal was significantly lower in amplitude and therefore more susceptible to earthing faults and EMI injections on the bus. PROFIBUS makes use of a balanced signal. This means that the signal transmitted on the A and B channels have similar voltage levels, however, they have opposite polarities. The differential signal is calculated as B – ( – A). When a short occurs on the PROFIBUS cable between either of these cores and the PROFIBUS cable shield, the shorted core will

How to achieve high PROFIBUS network availability

The difference between three 9's (9.99%) and four 9's (99.99%) availability on your PROFIBUS communications network could mean millions of Rands in lost production that directly affects your bottom line. Network rigidity and availability should be the core focus of any automation engineer who is tasked with maintaining a plant's PROFIBUS communication system. There are four main areas to focus on that will assist in improving your 9's score on any given network: 1) Training Fundamentally important, ensuring that all personnel who work with the network have the necessary training and know-how. Your local PROFIBUS / PROFINET Training Center will have a set of certified courses to ensure that all attendees are competent to handle installations and design scenarios. The following courses should be considered for PROFIBUS networks: Certified PROFIBUS Installers Course Foundation PROFIBUS Training Course, imparts knowledge on the PROFIBUS specificatio

Common pitfalls when installing a Modbus RS485 network on site

Last week IDX were called to site at  a large commercial residence building in Pretoria, South Africa. Where our  client was implementing an IoT solution for remote monitoring and control of various HVAC and power systems in the building.  The control system the SI chose in this case was a Modbus enabled Industrial Micro PC called the Revolution PI. The client had Modbus sensors connected to boilers, air conditioning systems, ventilation systems and power meters. The Modbus  communications between the controller and the sensors were intermittently failing due to various installation and implementation faults: 1. Earthing and Shielding Within any fieldbus communication installation, one of the requirements to ensure uninterrupted operation is to implement adequate grounding and shielding techniques. Effective grounding and Shielding help to prevent electrostatic and electromagnetic pickup, which can lead to failed communications. Some of the shielding and grounding req