Change of Value (COV) messages are a smart, efficient way for BACnet devices to communicate updates in real time. Instead of constantly polling for data, COV messages let devices report only when something changes—like when a temperature sensor hits a new threshold or a fan status flips from off to on.
But like anything in OT networks, too much of a good thing can turn into a problem.
Let’s fix it.
What Are Excessive COV Messages?
When configured properly, COV messages keep your building automation system running smoothly. But sometimes devices are set up—or, more likely, left at default values—to report too frequently. The result? Excessive change of value messages that clog your network, cause slowdowns, delay command responses, and make the system less stable overall.
Finding and fixing those excessive COV messages used to be a frustrating manual process. But not anymore.
A Faster Way to Diagnose Excessive COV Traffic
With OptigoVN, identifying excessive COV traffic is nearly instant.
Let’s take a real-world example. One of our clients was experiencing intermittent network performance issues and suspected it could be due to excessive BACnet traffic. When they ran a diagnostic test in OptigoVN, the results flagged potential excessive COV messages right away.
A quick glance at the diagnostic overview showed exactly which devices were sending out COVs in rapid succession — way faster than needed. One device was sending more than 7,100 COV messages an hour. That’s not just noise; it’s a flood.
Clicking into the alert gave the team instant access to the source address and device details. No digging. No packet captures. Just clear, actionable data.
From there, it was a simple process to search the device tab by source address, pull up the IP and MAC addresses, and get the BACnet device ID. That gave the technician everything they needed to adjust the configuration and reduce message frequency — or disable unnecessary COV points entirely.
Stop the Noise Before It Disrupts Your Network
Whether you’re commissioning a new building or troubleshooting an existing one, knowing where excessive COV messages are coming from helps you keep your BACnet network stable and responsive.
OptigoVN gives you the visibility and tools to do that work quickly — no deep-dive manual testing required.
With Optigo Visual Networks, client OT network monitoring and troubleshooting just got easier. To find out for yourself, register for a free account and start exploring today.
