speedcheck digital variable speed limit sign display

SpeedCheck® Variable Speed Limit Signs

Variable speed limit signs are durable, high-visibility illuminated signs that alert drivers to scheduled and spontaneous speed limit changes.

SpeedCheck® Variable Speed Limit Signs

Alert drivers to scheduled and spontaneous speed limit changes using durable, high-visibility illuminated signs.

Take a drive on any road in North America and you’ll see them: rectangular, black-and-white signs at the edge of the road that tell you how fast you can safely travel. While the speeds displayed on these signs are appropriate under typical conditions, they fail to provide safe thresholds for speed when traffic and/or weather conditions deviate from the norm. Whether it’s poor weather, road work, holidays, or something else impacting conditions, modifications to posted speed limits are often necessary.

This is where variable speed signs (VSLs) come in. Commonly implemented on highways and other high-volume corridors, but equally relevant to school zones and work zones, variable speed signs can be programmed and adjusted by local authorities to display speeds that are reasonable and safe for the current conditions. According to the FHWA, “By using VSLs, agencies can take into account traffic volume, operating speeds, weather information, sight distance, and roadway surface condition when posting speed limits.”

Carmanah’s variable speed signs, which are part of our best-selling SpeedCheck product line, employ industry-leading high-contrast display technology to ensure visibility and compliance in all weather and lighting conditions. Both the 15- and 18-inch-digit models—which are designed for roads with speed limits below and above 45 mph, respectively—feature an ultra-bright white-on-black LED display embedded in a highly recognizable regulatory speed limit or school zone speed limit sign. Quick to install and simple to configure using the included SpeedCheck Manager software, variable speed signs offer transportation departments an affordable and effective method for increasing safety in all driving conditions.

Where are variable speed signs used?


 Features and benefits of VSLs

Superior visibility – Our industry-leading high-contrast display technology ensures viewibility in all weather and lighting contitions.

Simple scheduling – The included SpeedCheck Scheduler software makes it easy to set schedules with multiple timetables and exceptions.

Real-time adjustments – Make changes on the fly using a remote ethernet or local Bluetooth connection.

Precise traffic data – Onboard radar collects and stores detailed traffic data like time, date, and travel speed. Reports can be generated and downloaded using the included Traffic Analyzer software.

AC and solar power options – Installation is possible virtually anywhere with off-grid power and a Solar Power Report prepared for every location.

FHWA/MUTCD compliant – Compliance reduces your risk, meets requirements for federal funding, and provides the benefit of driver familiarity with sign faces, colors, sizes, and shapes.

Want to see all the features and specifications?


When slower really means faster


Studies show that traffic flowing more slowly, smoothly and consistently actually helps motorists get to their destinations more quickly. Fewer rear-end and lane-changing accidents occur in slow-but-steady conditions, and both fuel usage and carbon emissions are decreased.

Increasingly, departments are using variable speed limit signs on highways to alert drivers of changing road conditions ahead in real-time. Traffic management center (TMC) operators can make incremental adjustments to speed limits to respond to vehicle breakdowns, crashes, heavy congestion, or weather, ensuring that traffic slows down but keeps moving, and ultimately gets to their destination faster.

Variable speed limit signs give us the ability to warn drivers in advance that they are approaching heavy congestion or a crash site, and to slow down that approaching traffic to a safe speed—one that will best facilitate its movement through the area. This will be immesurably safer than having to slam on the brakes when suddenly confronted with backed-up traffic.

– Russell McMurry, GDOT Chief Engineer

A SpeedCheck sign for every application


In addition to our SpeedCheck variable speed limit signs, Carmanah offers two additional SpeedCheck products proven to decrease speeding and improve safety in neighborhoods, school zones, highways, and more. Both systems feature our signature, ultra-clear display, increasing visibility and driver awareness, while reducing travel speeds. All SpeedCheck signs are MUTCD compliant, Transportation Canada approved, and aligned with walkability and traffic calming initiatives. Select one of the systems below to learn more.

carmanah speedcheck-15 radar speed sign with 25 digits

Driver feedback radar speed signs refocus drivers’ attention and can reduce speeds by up to 9 mph

speedcheck advisory radar speed sign

Advisory speed signs reduce road departures and improve safety on rural roads and exit ramps

A trusted name in traffic

SpeedCheck is the most recognized radar speed sign in the industry, with thousands of installations across North America. It was the first system with an integrated LED and radar display and it remains a market leader 20+ years later. The SpeedCheck system features a unique, ultra-clear display that increases contrast and viewability while also improving driver focus with its proprietary safety mask.  All SpeedCheck systems are proudly MUTCD and Buy America compliant.