JSON Toolkit for Niagara 4 Now Available

By Matt

Tridium has created a new JSON Toolkit for Niagara 4 software that enables it to “speak” JSON. You can see their press release here. This is important, because much of the Internet speaks JSON in the background. A JACE that speaks JSON is starting to look like that futuristic IoT device we’ve been promised for…

BACnet Frequently Asked Questions

By Matt

What are BACnet devices? BACnet stands for Building Automation and Control network. It is a communication protocol created by the American Society of Heating, Refrigerating and Air-Conditioning Engineers to allow manufacturers of building automation equipment to create devices that can inter-operate with each other. It’s a standard protocol with worldwide adoption. The idea is that…

Override BACnet Input Objects

By Matt

Have you ever had an outside air temperature sensor fail, causing a building’s automation to go nuts? Instead of overriding the entire building, why not just override the sensor? Usually with building automation systems you have to explicitly program this functionality. This is an area where BACnet shines: the protocol was designed by ASHRAE with…

BACnet Object Types

By Matt

The BACnet standard supports at least 18 different BACnet objects. ASHRAE will add new object types from time to time, but it’s rare to see these exotic object types in the field. The common objects provide intuitive access to building automation features. There is a loop object for PID loops, a calendar object for holidays…

MS/TP Capture Tool now Included with Wireshark!

By Matt

Wireshark is a fantastic tool for network diagnostics. It’s been the best tool for BACnet/IP network troubleshooting for years. It’s even been able to dissect MS/TP traffic dumps if you knew how, and had the right tools. Check out the new Wireshark BACnet MS/TP capture tool, included in 2.4.4 (and possibly earlier), which includes those…

What Is BACnet?

By Matt

The Basics – What is BACnet? BACnet is a popular building automation protocol used worldwide to enable communication between devices in commercial automation systems. Industrial automation has historically used other protocols such as OPC and Modbus. BACnet standardizes communication across vendors and simplifies the integration process. The name BACnet stands for building automation and control…

Overview of Commercial Automation Protocols

By Matt

In automation there are several communication protocols. Some are entirely proprietary and others are open. Despite the friendliness of the word, “open” isn’t always good news. Some of the older proprietary protocols are easy to integrate with off the shelf integration products. Two versions of the same protocol often look different. It’s a zoo out…

Add a Remote Device Without a BBMD

By Matt

You may encounter a situation where you must add a device on a different network. You may have no control of the BBMD configuration or you may have no BBMDs available due to poor device support. In these situations, you may have to add a remote device without a BBMD. It’s a handy trick, but…

When and Why Do We Need an End of Line Termination?

By Matt

End of Line Termination Concept Most of the buses we use are specified with end of line termination in mind. In the field these terminations are not always present, especially in short runs. Do we need them? Here’s an analogy I like that illustrates why we need end of line terminations: a bus behaves like…

RS-422 – The Other Bus-meat

By Matt

I encountered an RS-422 bus for the first time recently and it threw me through a bit of a loop! The device was a Modbus/RTU slave device and so I anticipated a RS-485 connection as per usual, but that was not the case. It’s the same cable, and the same essential signalling standard, but if…