Goodbye Legacy L4X Controllers…Hello Faster, More Flexible Ethernet Controllers
Written by Greg Weichman, Revere Networking & Controls Product Manager
Believe it or not it has been 18 years since the launch of the CompactLogix; which brought the capabilities of the RSLogix 5000 software to a mid-range platform for the first time. Since it’s launch in 2001, many advances have taken place - two generations of hardware have come and gone, and it is now time to say farewell to the last available controllers of that era.
Rockwell Automation has recently announced the following discontinuations:
July 2020 - The 1768-L43 and 1768-L45 controllers
December 2020 - The 1769-L32E and 1769-L35E controllers
Once they have been discontinued, they will no longer be available for purchase. We know that many of our customers still rely on these controllers, but there are many reasons why moving into one of the new platforms is a blessing in disguise.
Increased Hardware Capacity
To start, none of these processors have the capability to go beyond version 20 of RSLogix 5000. This isn’t a planned obsolescence maneuver, but rather a matter of hardware capability. The newer generations of 1769 and 5069 controllers have more processing cores and more internal memory (separate from the programming storage) which is needed to enable new features; such as, project documentation storage (i.e. tag descriptions and rung comments), extended tag properties, program parameters, integrated motion support, integrated safety, and more.
Faster Scan Times
Another benefit is that scan times are much faster with modern controllers - with programs executing anywhere from two to twenty times faster. This new hardware is utilized to its fullest extent by programming it with the latest releases of Studio 5000. Version 20 of RSLogix 5000 is continuously being updated to remain current with Microsoft Windows, but it has not received any new features since its release in 2012, nor will it in the future.
Release of the 5069-Serial Module
In 2001, when the CompactLogix family first launched, Ethernet was not a prevailing technology in most industrial applications. Many applications required serial communications and the L32E and L35E have a serial port on the front making it a simple solution. Even though serial communications are becoming dated, the lack of a serial port on newer controllers prevented some people from being able to use them and take advantage of the newer technologies. Rockwell listened and we are happy to announce the release of the 5069-Serial module. This two-port device can be used as local or distributed I/O to support applications needing to talk ASCII, Modbus RTU, and Modbus ASCII. Mid 2019 the DF1 Serial protocol will be supported and more protocols will be added with future firmware releases. Sample programs can be downloaded from Rockwell’s Sample Code Library.
Two Ethernet Ports, Setup with the Same IP Address
Continuing with the Ethernet discussion, often a PAC needs to talk to two separate Ethernet networks. The most common example is when there is a need for a private network for IO and a public plant network for typical network devices. Previously, the easiest way for a Controls Engineer to achieve this was to use a 1768 controller, because the chassis could support two Ethernet cards and each one could be setup for a different network. For this reason, many people continued to use the 1768 controller, even though they were giving up all the useful features mentioned above. Now, we have multiple solutions for this situation. The 1769 platform has two Ethernet ports, but they are setup to have the same IP address, and therefore to be used in a linear or device level ring (DLR) topology on one network. To allow these controllers to talk to another network, we use a Network Address Translation (NAT) device such as the 1783-NATR, 9300-ENA, or select Stratix 5700 switches. The newest 5069 platform also has two Ethernet ports on each controller, but they are more configurable than the 1769. They can be setup to act in the same manner as the 1769 ports (for linear or DLR) or they can be configured to have two separate IP addresses, allowing the controller to natively talk to two separate networks the same way a 1768 rack with two Ethernet cards could. (Note, if you are using the 1768 platform for Sercos, the two directions forward are ControlLogix or migrating toEethernet based CIP motion devices.)
Simple Ethernet/IP Node Count
I am sure it will be of no surprise to any of you when I say that the number of smart devices being used in manufacturing increases every day.Our programmable controllers need to be able to communicate with every smart device, so the number of Ethernet connections available on newer controllers increases exponentially. With the older generation of controllers, calculations had to be done with devices on the network to determine TCP and CIP connections to make sure limits weren’t exceeded. Limits in an L32E processor were low with only 32 available of each, causing difficulty scaling with modern applications. Max Ethernet/IP connections would also decrease with increasing RPI creating even more confusion and frustration. Current 1769 and 5069 controllers have gone away from this confusing math by implementing a simple Ethernet/IP node count. All you must do is count the number of devices that will be in the I/O configuration of the project and then make sure to select a controller that will support the count (pro tip: plan some room for growth).
To recap, today’s systems are becoming more connected than ever before. Factory operators want to connect their equipment and contextualize data, so they can make educated business decisions in real time. Older control systems lack the processing and communication power to fit into today’s Connected Enterprise. Modern control systems provide ample connectivity, a new level of capability, greater ease of use, and more security. Luckily, converting applications among the families of CompactLogix is easily achievable with Studio 5000 software.
Revere’s team of automation specialists can help you modernize existing systems, bills of materials, and network architectures so you can take advantage of all the features we discussed today. Please reach out to your Revere Account Manager or Revere Specialist if you are interested in learning more or would like us to come out to evaluate an application.