DVSA Weigh in Motion Sensors (WIMS)
The Driver & Vehicle Standards Agency (DVSA formally known as VOSA) have various special Weigh in Motion Sensors (WIMS) and Automatic Number Plate Recognition (ANPR) cameras installed all over the country. Helping them win the fight against overloaded vehicles which pose a threat to other road users and cause significant damage to the road infrastructure.
A combination of WIMS and ANPR cameras have replaced the old manual weight control systems to make it easier for Officers to track the offending vehicles down. Induction loops and special sensors that comprise of piezo-electric strips are embedded into the road’s surface to determine the weight of the passing vehicle. See below.
At the same time the ANPR camera records the vehicle’s registration number.
How does it work?
The system recognises the vehicle and measures its speed and weight, it then compares these findings with the information in the DVSA database. If the vehicle is overloaded, the system sends an alarm to the supervising officer, they then inform the nearest traffic police patrol car about the suspected vehicle. The officers stop the vehicle further along its journey and direct them to the nearest control point. On average they pull over four trucks per hour.
The scales mounted on these British roads are so accurate that in almost every case, the suspected overloaded vehicle is re-weighed on a set of axle pads or weighbridge at the DVSA control point and the original reading is confirmed. The driver/company is then given the appropriate fine and actions take place to lighten their load before they can continue with their journey.
Below is an example of the alert screen
- The green ellipse indicates the WIMS weight reading.
- The yellow ellipse contains the maximum that the vehicle can weigh according to the database.
- The white ellipse shows how much the vehicle is overloaded on each axle and the total weight in percentage.
- The red bars inform which axles are overloaded and the green bars show which are not.
- The Operator Compliance Risk Score (OCRS) provides information on possible previous infringements of the given carrier.
It is important to know that the system also recognises vehicles from abroad even if their data does not appear in the DVSA database. Approximately 50% of the overloaded vehicles are known to be from overseas.
DVSA officers are also alerted if the driver is speeding. Most vehicles of this size are fitted with speed limiters so the police patrol car can pull the vehicle over to check it hasn’t been tampered with & take appropriate action for the offence.
Where are the WIMS located?
The agency does not provide information on the location of the WIMS, however there are known to be sites in action on the M25 near Leatherhead, also Perry Bar & Dartford. It is also known that there are at least 11 more in “strategic points of UK road infrastructure”. It must be noted that it is NOT possible to get around the sensors on the hard shoulder.
How do we ensure our fleet is not overloaded?
The equipment needed to check your fleet is not overloaded is either a weighbridge or an axle pad system that are regularly calibrated. Solent Scales can offer both products and calibration when needed. You can read more about overloading fines & consequences in our blog here.