The folks at Fluke recently published an informative article outlining the key differences between “office grade” and industrial Ethernet. While there are similarities, many of the characteristics of
“standard” Ethernet would be ineffective or even dangerous when dealing with mechanical or other processes. The article details the changes made by the IEEE to make Ethernet more responsive and reliable, including timing and topology. It also covers hardening of cabling and connectors based on the M.I.C.E. (mechanical, ingress, chemical/climactic and electromagnetic) parameters. And, since it’s from Fluke Networks, it finishes up with a survey of different types
of test tools that can be used to check cabling to prevent and troubleshoot problems. Have a look at: https://www.flukenetworks.com/blog/cabling-chronicles/industrial-ethernet-vs-commercial
The folks at Fluke recently published an informative article outlining the key differences between “office grade” and industrial Ethernet. While there are similarities, many of the characteristics of
If you have come across a similar situation where you cannot connect Ethernet to Allen Bradley Controller, then you have come to the right place. One of the major reasons why people fail to connect to Allen Bradley Ethernet-enabled devices is probably because their system’s IP address has not been properly configured or the network adapter of the PC is set up for DHCP. In general, network adapters of computers are set up for DHCP by default and they need to stay the same so that they can be connected to the majority of companies and home-based routers.
ALLEN BRADLEY PLC is an industrial computer control system that will enable you to utilize the majority of the industrial processes. Your system’s network adapter has to be set up in a way that it has a static IP address so that you can connect your system to Allen Bradley Ethernet-enabled devices. Let’s take a rundown at things and how you have to set up the PC and the device. Starting with the PC first,
- Ensure that the Allen Bradley device is able to communicate over IP or Ethernet. If the cable has properly fitted into the port, in no way does that mean that you are using the correct one? Even the wrong ones can fit into the port appropriately and a lot of Allen Bradley devices use RS485 ports which are the same as the ones in Ethernet cables.
- Ensure that all the devices are powered up properly and the cables are well-connected.
- Ensure that the correct software is installed on your computer to enable connectivity and communication with Allen Bradley Controllers and Drivers.
- Once everything is in place, configure the IP address and subnet for your computer. This is where the problem lies, as already stated above most PCs are set up for DHCP by default so you have to make sure that they have a static IP address.
Given below are the steps you can follow if you want to set a static IP address on your system:
- Click on the start menu on your windows system and select “Control panel.”
- After that, select the option “Network and Sharing centre.”
- Do you find the option “change adapter settings”? Click on it.
- Select “Properties” once you right click on “Local Area Connection.”
- Now, click on the option “Internet Protocol Version 4” and then select “Properties.”
- You will see two options now- choose the one that says “Use the following IP address:” Here you can set the IP address but, if you want to change the settings back to the company’s network then choose the other option.
- Once you are done setting the IP address and subnet then click on “OK”.
- You will see a “Local Area Connection” window, select OK again.
That’s it! Your IP address has been set up on your system and it has been configured. Now, you can successfully connect to Allen Bradley Ethernet-enabled devices.
Allen-Bradley’s most popular automation controller lines are ControlLogix and CompactLogix. The ControlLogix is designed for larger, heavier systems that require higher I / O numbers. The CompactLogix is better suited to smaller systems with its simpler, more compact case. We shall look in-depth here at the variations of these both processors.
Two models are sold on the CompactLogix range–a customizable chassis-free and an all-in-one chassis system. CompactLogix L23, L1XER, and L2XER are the most popular all-in-one controls. You might have learned from this if you’ve used CompactLogix processors, which are best-selling processors in the line. The best-selling components for modular systems are the L30ER, L33ER, L32X, and L35X.
The CompactLogix bundled processors are equipped for operating out-of-the-box, their biggest value. Conversely, the L3 systems are flexible and often combined with the local I / O network. They require a separate power supply as well as a dedicated End cap. Consumer specifications for the CompactLogix processors equivalent to L1, L2, and L3 are 5380. The main features of 5380 CompactLogix processors are SD card Slot for non-volatile memory use, Integrated USB port Included with 1 GB of memory is the USB SD Card with an embedded Super Cap –batteries are not required.
The ControlLogix sequence was the initial model for Logix. It was published in 1999 for the first time 20 years ago. The ControlLogix controllers are versatile and include electricity supply, a CPU, chassis, connectivity devices and/or I / O modules. It is an advanced controller used for larger and much more complicated systems, that’s why it’s more expensive than a CompactLogix controller.
While the chassis and power supply did not change significantly since 1999, the new generation of processors and communication modules changed. The first model in 1999 was 1756-L1, followed by the L55, known as 5555. Instead of a built-in memory module, this controller has expandable memory and the base device has no default memory, which means that users must order a certain amount of memory before purchasing.
The newer L6x was the first non-volatile CompactFlash controller to be installed. Similar to EEPROM, this memory could be deleted and reprogrammed on an older computer. The L7 has received some improvements, like the SD card slot and the super capacitor charging module.
Lastly, the latest addition from Rockwell is the L8x, better known as the line of processors of 5580 ControlLogix. The main difference is the performance, which in program scans is 20 times faster. It also has an Ethernet port of 1 GB, improving connectivity and volume.
CompactLogix vs ControlLogix Comparison Table
|Characteristics||ControlLogix 5580||ControlLogix 5570||CompactLogix 5380||CompactLogix 5370 L3|
|Controller Tasks:||32/1000 programs/task||32/1000 programs/task||32/ 1000 programs/task||32/1000 programs/task|
|User Memory:||3 MB (1756-L81E) to 20 MB + 6 MB safety (1756-L84ES)||2 MB (1756-L71, 1756-L71EROM) to 8 MB + 4 MB safety (1756-L73S, 1756-L73EROMS)||0.6 MB (5069-L306ER, 5069-L306ERM) to 10 MB + 5 MB safety (5069-L3100ERS2, 5069-L3100ERMS2)||1 MB (11769-L30ER, 1769-L30ER-NSE, 1769-L30ERM, 1769-L30ERMK) to 5 MB + 1.5 MB safety (1769-L38ERMS, 1769-L38ERMSK, 1769-L38ERMOS)|
|Built-in Ports:||Single-port Ethernet port, 10 Mbps/100 Mbps/1 Gbps, 1-port USB client||1 Port USB client, Dual-port Ethernet/IP 10 Mbps/100 Mbps||2 Ethernet ports, 10 Mbps/100 Mbps/1 Gbps, 1-Port USB client||Dual-port Ethernet/IP 10 Mbps/100Mbps, 1-port USB client|
|Communication Options:||EtherNet/IP, ControlNet™, DeviceNet™, Data Highway Plus™, Remote I/O, SynchLink™,USB Client||EtherNet/IP, ControlNet™, DeviceNet™, Data Highway Plus™, Remote I/O, SynchLink™,USB Client||EtherNet/IP,USB Client||EtherNet/IP:Embedded Switch, Single IP Address,DeviceNet,USB Client|
|Controller Connections:||Not Applicable||500 Connections||Not Applicable||256 Connections|
Looking at the table, we can see that, although there is only a single generation gap, ControlLogix 5580 or 5570 are quite homogeneous. In controller connections, there is quite a difference in both processors. 500 connections are applicable to ControlLogix 5570 whereas there is no connection supported by 5580. ControlLogix 5570 features an Ethernet / IP port with a maximum speed of 100 Mbps, which is a previous generation controller. On the other hand, 5580 can go up to 1 Gbps, which is a huge speed and reliability improvement.
On the memory side, the security of 5580 and 5570 lags is maximal 20 MB + 6 MB at maximum and the maximum memory is 8 MB + 4 MB.
Talking about the CompactLogix, there is another significant difference between generations. The newest 5380 comes with an Ethernet port of 1 Gbit / s with a maximum memory capacity of 10 MB+5 MB, whereas the 5370 comes with 5 Gb / security. In comparison to the previous generation, Allen Bradley made significant improvements.
Before the introduction of Foundation Fieldbus, the gateway to the industrial automation started with parallel wiring, where the devices were connected independently with the rule and control level.
However, with the increased levels of automation, the number of participants also increased. This led to a high wiring expenditure. Hence, it was extensively replaced by economical and faster Fieldbus systems.
Foundation Fieldbus systems are targeted for platforms using advanced as well as primary regulatory control, along with some of the discrete commands associated with those functions. The technology was previously used in the process industries; however, with recent advancements, Foundation Fieldbus are now being applied in power plants as well.
Definition of Fieldbus
Field and Bus make Fieldbus. A field is a geographically limited area. In an engineering world, it is intellection of the plant levels. Bus, on the other hand, is a set of a standard line that electrically links multiple circuits for transferring information.
The idea behind Fieldbus is to eliminate any point-to-point links between the field devices like actuators and sensors and their controllers by a single digital connection on which all the information is communicated consecutively in serial order and multiplexed over time.
In most cases, the Fieldbus transfers the information in small packets in a sequential manner. The subsequent transmission of information decreases the total required number of connecting lines over greater distances than that of parallel transfers.
Examples of Fieldbuses
- Interbus– it has a transmission rate of up to 2 Mbps, which is characterized by high transmission security and constant, but short cycle time.
- Profibus– it is used in manufacturing automation and engineering industries. It has a transmission rate between 9.6 kbps and 500 kbps. It uses a hierarchical structure with the actuators and sensors levels.
Within the process automation environment, there are two related applications of Foundation Fieldbus. They use different communication speeds and physical media.
- The H1 segment operates at 31.25 kbit/s. H1 segments are usually used for connecting host systems and field devices. As compared to standard twisted-pair wiring, H1 segment offers more power and communication in both intrinsic and conventional safety applications. It is the most popular Foundation Fieldbus application.
- High-Speed Ethernet (HSE) operates at 100/1000 Mbit/s and is used for connecting gateways, host systems, subsystems, and linking devices. However, HSE doesn’t provide power over the cable, for now.
Benefits of Foundation Fieldbus
- Multidrop wiring
- Multivariable instruments
- New types of information
- Two-way communication
- Control in the field
- Interchangeability- devices can be functionally interchanged without changing the functionality
- Interoperability- devices can communicate with each other while performing in multi-vendor environments with ease
What does this mean?
Considering the mentioned benefits of Foundation Fieldbus, there are plenty of reasons why it is implemented in many automation industries. So of them are as follows:
- Speed – Systems can be installed and organized more quickly
- Reliability – Short signal paths mean increased availability and reliability
- Interference reliability – Increased protection against interference
- Uniformity – The use of unified connection technology and standardized bus protocols enable the use of different devices from different manufacturers
- Flexibility – Modifications and expansions can be implemented quickly with ease
How to split the DF1 Port of SLC500, MicroLogix, CompactLogix, PLC5, ControlLogix or any Allen Bradley DF1 Port Device.
In case you have the serial DF1 port of an Allen Bradley PLC, like PLC5, SLC 5/05 1747-L551, SLC 5/03 1747-L533, CompactLogix 1768, CompactLogix 1769, Control Logix 5563, MicroLogix 1400 (1766 MicroLogix ), MicroLogix 1200 (1762 MicroLogix ), MicroLogix 1100 ( 1763 MicroLogix ), MicroLogix 1000 ( 1761 MicroLogix ), or any DF1 device where the DF1 port is already being used and you want to connect another DF1 device to it, usually you would get the Allen Bradley 1747-DPS1 DF1 port splitter but that is being discontinued by Allen Bradley and now your best solution out there is Equustek’s DL4000-DFX which allows three DF1 serial devices to simultaneously communicate with each other, below is the link to DL4000 page .
The DL4000 can be programmed with other firmware versions to perform other protocol conversions, such as;
DL4000-DMX allows DF1 to communicate with MODBUS and can be configured for MODBUS master or MODBUS slave, it also can be configured to connect via RS232, RS422 or RS485.
DL4000-MMX interfaces MODBUS RTU to MODBUS ASCII (Allows Modbus RTU devices to communicate with multiple Modbus ASCII devices), also can be configured to do RS232, RS422 or RS485.
DL4000-DAS Interfaces serial ASCII devices (Scanners/Printers) to AB DF1 protocol.
DL4000-MAS Interfaces ASCII device to MODBUS RTU Slave.
DL4000-PM Provides a DF1 Half Duplex Master Interface to Allen Bradley Power Monitor 3000 then sends the converted data via Modbus to specified Slave RTU devices.
Equustek’s DL3500-DF1/DH+, a direct replacement for Allen Bradley’s 1770-KF2 or 1785-KE, DF1 to Data Highway Plus (DH+) Interface
Many Allen Bradley PLCs, like MicroLogix 1400 (1766 MicroLogix ), MicroLogix 1200 (1762 MicroLogix ), MicroLogix 1100 ( 1763 MicroLogix ), MicroLogix 1000 ( 1761 MicroLogix ), CompactLogix 1768, CompactLogix 1769, SLC 5/05 1747-L551, SLC 5/03 1747-L533, and other manufacturers Distributed Control Systems (DCS), like the Honeywell DCS (TDC 3000) or the Emerson DeltaV DCS with PSIC (Programmable Serial Interface Card) that have a serial RS232 DF1 port, most of the time they need to communicate with an Allen Bradley Data Highway Plus (DH+) device like the PLC-5, SLC 5/04, ControlLogix 1756-DHRIO, a Panel View, or any other DH+ device. The solution for that used to be using one of Allen Bradley’s 1770-KF2 or the 1785-KE to interface between the DF1 and DH+ by connecting the DF1 side to the RS232 DF1 port, while the other side (DH+) would be daisy chained to the Data Highway Plus Network, but Allen Bradley phased out the 1785-KE and 1770-KF2, both now are obsolete. So what options are out there for the plant to continue working until they are ready for an upgrade to Industrial Ethernet IP?
The Equustek DL3500-DF1/DH+ is a direct replacement for the Allen Bradley 1770-KF2 and the 1785-KE, in all those cases previously mentioned, the DL3500 will be transparent where any of the above mentioned PLCs or DCS will look like any other DH+ device or PLC node on the Data Highway Plus Network allowing communications between all of them.
An application note showing how to setup and configure the DL3500 DF1 to DH+ allowing a MicroLogix 1000, SLC 5/05 1747-L551 and a SLC 5/03 1747-L533 and make them communicate like any other DH+ PLC on the Data Highway Plus Network ( DH+ ) then using RSLINX and RSLOGIX 500 to go online with them, are available from this link.
In any case, when you have the discontinued Allen Bradley legacy 1770-KF2 or the 1785-KE damaged by lightning or any other failure and needs to be replaced, your best solution is the Equustek DL3500-DF1/DH+, as it is a direct replacement for the AB 1770-KF2 and AB 1785-KE.
Similar to Allen Bradley’s 1770-KF2, 1785-KE and 1784U2DHP, the DL3500-DF1/DH+ will allow your PC HMI SCADA running with any RS232 DF1 driver or RSLINX 1784U2DHP driver to communicate with and go online with all DH+ nodes (PLC-5s & SLC 5/04s) that are connected to the Data Highway Plus network where the DL3500 DH+ port is connected to as well.
The DL3500 DF1 side has many physical options to connect serially though RS232, RS422, RS485 & USB with baud rate setting configurable range from 4800 to 115200 baud and the DH+ with baud rates of 57.6KB, 115.2KB and 230KB, the DL3500 can be powered from the USB or an external DC 9-27V.
More details and other application notes on Equustek DL3500 can be found from this link.
If you are in a situation where you have an Allen Bradley MicroLogix 1400 with MODBUS TCP/IP support, and you want it to communicate with the DH+ network devices like Allen Bradley’s PLC5 and SLC5/04, where the MicroLogix Ethernet port is configured for MODBUS TCP/IP Master so that it can get data from any DH+ Device ( PLC5s and SLC504s), or the other way when the DH+ Nodes or devices like PLC5 or SLC5/04 wants to get data from MicroLogix which it’s Ethernet port is configured in this case for MODBUS TCP/IP Slave, that said not many easy affordable solutions are out there, however Equustek Solutions DL6000-MEDH+ can do it easily, when it is configured as a Slave where the MicroLogix is Ethernet port is configured as a Master.
Here the DL6000-MEDH+ will allow the MicroLogix to communicate with all PLC5s and SLC504s or any Allen Bradley DH+ node connected to the same Data Highway Plus network which the DH+ port of DL6000-MEDH+ is connected to, that is accomplished when the MicroLogix MODBUS connects to the IP address of the DL6000-MEDH+ then by using the DH+ nodes address numbers as MODBUS Slave IDs to address the PLCs and SLC504s.
Also when the DH+ PLC5s or SLC 5/04s are initiating communications and are requesting data from the MicroLogix then the DL6000-MEDH+ Ethernet side will be configured as a Master while the MicroLogix Ethernet port will be configured as a MODBUS TCP/IP Slave.
Here the DL6000-MEDH+ will allow any DH+ device to request data from the MicroLogix.
More details about the DL6000-MEDH+ can be found from the link below.
DL6000-MEDH+ as A Master Application Note link below
DL6000-MEDH+ as A Salve Application Note link below
Allen Bradley 1784-PKTX, Woodhead SST-DHP-PCI / 5136-SD-PCI, Equustek DLCPIe and Microsoft Windows Security Support
If you have an Allen Bradley 1784-PKTX or SST’s SST-DHP-PCI / 5136-SD-PCI on a desktop running Windows 7, we all know that on Jan 2020 Microsoft will stop releasing security updates for Windows 7, which means you need to upgrade to a new desktop running a newer Windows version, like Windows 10.
The problem you will run into upgrading your system is that Allen Bradley and SST Woodhead are not making the card for new desktop computers that have the PCI Express bus, however, Equustek has the solution with their DLPCIe that comes in two hardware versions, one for DH+ and another for DH485, which can reside in any new desktop with PCI Express bus X1 ,X2 X4, X8 and X16 and drivers are available for all Windows versions including Windows 10 32 bit and 64 bit.
Equustek DLPCIe has another advantage by adding a 9 pin DSUB regular RS232 serial communication port which most of new desktops don’t come with, that serial port can be used for any RS232 serial communications that will facilitate connecting your RS232 serial device to your desktop.
For details see links below.
Profibus and Profinet are two terms that are often confused with each other, both of them being field networks part of industrial automation protocols. However, there are significant differences between the two in various aspects and for the same reason are used for different purposes in industries.
In order to clearly understand their functioning and application of the two, it is important to first get a good grasp of the basics.
Profibus which is the acronym for Process Field Bus is basically a standard for fieldbus communication used in automation technology. Profinet on the other hand, which is acronym for Process Field Net is a standard for internet communication over industrial Ethernet.
As they are both very popular and highly sought after automation protocols created by the same organization, they do share a number of similarities. They are both created and maintained by Profibus and Profinet International.
However, Profinet comparatively has extra advanced capabilities that facilitate a faster and a more flexible field of communication within a network.
They share the same application profiles; which essentially implies that they have similar guidelines followed by different categories of devices within a network, regarding their use of Profibus and Profinet data during communication. These profiles enable smooth planning and functioning of the automation systems and devices.
Other than that they are also very similar in terms of their engineering concepts and they use General Station Description files to define the hardware for each device. The file type however is different.
In simple terms Profibus is a classic and traditional automation protocol based on serial communication while Profinet is a newer enhanced automation protocol based on Industrial Ethernet.
Significant points of differences
Profibus and Profinet use GSD files for define the hardware for various devices. But as mentioned before, the difference lies in the type of file being used. Profibus uses ASCII files whereas Profinet uses XML files.
In terms of their base field, Profinet made the move from RS-485 to Ethernet to become more efficient and ubiquitous. It is a more adaptable and modern technology that helps organizations future-proof their processes.
Besides that, being based on industrial Ethernet, Profinet also enjoys a higher bandwidth, a larger size of message and unlimited amounts of address space. Separate controllers attached to the network may have to adhere to certain limitations in terms of address space, depending on their memory capacity and processor capabilities though.
Other than that, Profinet is faster than Profibus because of the provider/consumer model that it uses, where any node in the network is allowed to communicate at any given time. Hence, there is no delay in information exchange.
Besides that, Ethernet networks are generally switched networks that are practically devoid of network collisions.
Profibus uses a master/slave approach rather than a provider/ consumer model where the master is usually in charge of the entire network and the nodes are allowed to communicate only when prompted.
Usually industrial enterprises are required to deploy separate gateways in order to communicate with other networks. However, with Profinet, it creates its own proxies for translation and data exchange between two different networks and unlike an ordinary gateway they are defined in an open standard.
In case of Profibus, there is a facility for wireless transmission of messages; however, it requires similar based proprietary radios at both ends.
As Profinet works on standard Ethernet, it can easily use WiFi or Bluetooth for wireless transmission.
Even though Profinet is an enhanced and more versatile version of Profibus, it does not mean that the former can be used across industries regardless of the processes. It is important to study the field of automation and choose the protocol accordingly.
ControlNet is an open-sourced industrial network protocol. It is best suited for industrial automation applications. Interestingly, it is also known as a Fieldbus. This industrial network protocol caters to the demands of high-throughput applications required for automation. Another exciting feature of this industrial network protocol lies in the fact that it facilitates processes of discrete claims. It is based on the token-passing bus control network interface, which is of great use in industrial automation. In this context, it is essential to note that ControlNet uses the Common Industrial Protocol to facilitate interconnection between various levels of the Open Systems Interaction (OSI). There are seven layers of OSI, namely data link, network, physical, session, presentation, transport, and application.
The Design of ControlNet
ControlNet is designed in such a manner that it provides high-speed control and reliable data transfer by the usage of programming. This, in, turn, sets the logic to a specific timing over the network and facilitates faster data transmission. The ControlNet Network comprises of devices like the I/O chassis, programmable logic controllers, personal computers as well as drivers. In this context, it is vital here to note that ControlNet has a data transfer rate of around 5Mbps. This ensures that the data transmission within the industrial architecture always stays relevant.
The ControlNet Connectors that Help in Industrial Automation
It is important here to note that ControlNet cables are the RG-6 coaxial cable types with the BNC connectors. The connectors of BNC can either comprise of a twist on and locking type. It also sports a rugged design that is of the threaded screw type. This screw threaded design helps you to make sure that it can withstand harsher environments.
The ControlNet Cables That Are Used in the Network
ControlNet provides you the liberty to select the cable types. The cable types comprise of direct burial or flexible nature. Moreover, they are also designed in such a manner that they can be used in harsher environments. On the other hand, there are various applications for ControlNet that need longer distances and also use optical fiber in the cabling. It is important here to note that it can support a maximum number of 99 nodes on the network. Moreover, the repeaters also do not use the node numbers. This is the reason that they don’t count these nodes as a part of the maximum amount.
The ControlNet Data Link Layer
In ControlNet, the nodes are assigned with a MAC ID address 1 to 99. Moreover, each node also knows the address of the predecessor and the successor. Each node that is present in the ControlNet interface has a scheduled time, which is also known as a token. In the ControlNet network, only one node can be transmitted at a time which would eventually prevent the data collisions from taking dangerous propositions.
If ControlNet is set up correctly, it can be very stable and reliable. Moreover, over a longer period, it requires lesser maintenance when compared to other industrial automation networks.