SNAP PAC Standalone Controller with Four Serial Ports

Datasheet Download Link

SKU: SNAP-PAC-S2 Category: Standalone Tags: Communication, Digital, Ethernet, Processor

Now developer and IoT ready with a built-in HTTP/HTTPS server and RESTful API. See Programming, below.

** Compatible with groov—the easy way to build mobile operator interfaces and securely use them to monitor and control your automation systems and equipment from your smartphone or tablet. **

The SNAP-PAC-S2 programmable automation controller provides powerful, real-time control and communications to meet your industrial control, monitoring, and data acquisition needs.

Part of Opto 22’s S-series family of industrial controllers, the SNAP-PAC-S2 is fully integrated with PAC Project software, SNAP PAC brains, and SNAP I/O modules to form a complete control system. The SNAP PAC System includes digital and analog control, serial string handling, PID loops, and enterprise connectivity.

The SNAP-PAC-S2 is programmed using the included PAC Control software. PAC Control is a flowchart-based tool for developing control applications, or strategies. You create and debug the strategy on your computer and then download it to the PAC, where it runs independently.

REST API: All I/O point and strategy variable data is available for secure access using the built-in HTTPS server and RESTful API, with data delivered in JSON format. For complete API documentation and steps for getting started, see In addition, two Node-RED nodes are available. Note that minimum firmware R9.5a and PAC Project R9.5a are required to use the REST API.

You can build full-featured operator interfaces (HMIs) using the included PAC Display software, which taps the same tagname database you’ve already developed in PAC Control. OR take advantage of Opto 22’s groov to quickly build and view HMIs you can use on virtually any computer, tablet, or smartphone—any screen size, from any manufacturer—using just a modern web browser (like Firefox or Chrome). Learn more at

The controller is compact and industrially hardened. It includes two independent Ethernet network interfaces with separate IP addresses, which can be used to segment the control network from the company network or for redundant Ethernet links. You can also set up a system with redundant controllers using two identical S-series controllers, the SNAP PAC Redundancy Option Kit, and PAC Project Professional 9.0.

The SNAP-PAC-S2 controller is well suited for use with serial-based I/O units and serial devices. The SNAP-PAC-S2 has four serial ports that can be individually configured as either RS-232 or RS-485 (2-wire or 4-wire). Configured as RS-232, serial ports support serial device communication or a Point-to-Point Protocol (PPP) modem connection for creating a TCP/IP network over PSTN (Public Switched Telephone Network) lines. Configured as RS-485, serial ports connect to SNAP PAC Serial brains or to legacy Opto 22 mistic™ I/O units, including the serial B3000 brain and remote mistic bricks. (Note: If you are using the S2 with misticI/O units, use the legacy versions of the PAC Control, PAC Display, and PAC Manager guides.)

The SNAP-PAC-S2 can be panel or DIN-rail mounted. For DIN rail, see the SNAP-S2DIN DIN-rail mounting kit.

If you need a similar PAC that also communicates wirelessly, see the SNAP-PAC-S2-W.

If you need fewer serial ports, see the SNAP-PAC-S1.

For more details, see the Specifications tab and the data sheet under the Docs & Downloads tab. To compare controller features, see the SNAP PAC Controller and Brain Comparison Chart.