Building on a long history of hardware development in PLCs and I/O systems, Synergy Logic has introduced the SLM-MX remote I/O bus and expansion module system. These devices bear resemblance to I/O modules produced for the popular Productivity PLC system, produced by the same design team at Synergy Logic.
The Compact I/O From Synergy Logic
Remote I/O systems are modular versions of larger, rack-mounted PLC counterparts, but still provide most of the functionality. The remote racks (called nodes) are often more limited in the number of I/O points but still offer much of the same variety, so they are excellent choices for modular projects where the I/O is spread over a large area. The SLM-MX controller is a 24 VDC-powered module with integrated Modbus TCP support for up to eight I/O modules. The controller is designed to be used in an industrial setting with operating temperatures of 0 °C to 60 °C and DIN mountable features.
The new SLM-MX remote I/O system with modules attached. Image used courtesy of Synergy Logic
The MX series offers many different I/O options, including digital, analog, dedicated input or output modules, combination, and specialty modules such as thermocouple input modules. All of these I/O modules connect to the SLM-MX controller via connectors on the side of the module. Simply stack multiple modules together, connect to the controller, and engage the module locking mechanism.
Modbus TCP
Built on the TCP/IP protocol, Modbus TCP is a variant of Modbus that takes advantage of the long-distance and high-speed data transmission of the Ethernet topology. Modbus devices are connected to networks via Ethernet cables and switches. Devices are then capable of sending and receiving messages. This popular topology is used with many other industrial protocols and has been proven to be robust and reliable. The SLM-MX comes fully equipped with a Modbus TCP/IP port and can communicate with Modbus devices such as actuators and remote I/O modules.
Setting addresses is important with networked devices, and the SLM-MX system IP address is assignable with DHCP or with configuration software from Synergy Logic.
An example of a small automation project, commanding two robots. Image used courtesy of Unsplash
The Industrial Version of the Raspberry Pi 4
Synergy Logic, a US-based company out of New Port Richey, Florida, initially introduced SL-RP4, a compact, Linux-based Raspberry Pi, to the industrial world. The designers at Synergy Logic have industrialized the popular computer platform with a robust case, passive cooling, and DIN rail mounting features. The SL-RP4 can be used with the OpenPLC runtime, which comes preinstalled, to run small to medium automation projects.
The more recent release of the SLM-MX allows expansion of both this computer and nearly any platform with Modbus capabilities, virtually a standard offering across the PLC world.
Expanding the Reach of PLCs
PLC systems have come a long way from their first beginnings, where the device was merely a couple of programmable relays inside a box. Today, compact PLCs can support industrial protocols, motion, and many hundreds of remote I/O modules. These features make compact remote I/O units, such as the SLM-MX, an economical solution to small and medium-sized automation projects.
