The best of both worlds

Haenni Instruments has developed a wheel-load scale that combines permanent and mobile weigh enforcement stations

Words | Daniel Kneubuehl, Haenni Instruments, Switzerland

Mobile enforcement units remain popular as it is impossible for truckers to plan routes to bypass them

Why is it that mobile patrols are still used for weight enforcement when there are automated systems on the market that are much more sophisticated than a simple wheel-load scale?

When talking about weight enforcement, the main focus is the reduction of the number of overloaded vehicles. The main factors for the effectiveness of any enforcement are the probability of detection and the amount of the fine to be paid.

Permanent stations are very precise, but are also very likely to be bypassed by overloaded vehicles. Mobile weight enforcement is less efficient in weighing, but highly efficient in unsettling the drivers of overloaded vehicles. The bottom line is that weight enforcement with mobile scales is more effective.

Aware of the importance of its mobile wheel-load scales for weight enforcement, Haenni Instruments wanted to improve what was already an excellent solution.

What makes Haenni scales ideal for professional applications? This was the first question the in-house development team asked when they started designing a next-generation mobile wheel-load scale.

“Besides offering easy handling, reliability and durability for many years, and being able to be used for legal metrology, two essential characteristics are needed: an extended temperature range and the thinnest weighing platform possible,” says Micha Kernen, Haenni project engineer.

Thinnest certifiable scales

With a 17mm-high (0.67in) weighing platform, Haenni builds the thinnest certifiable wheel-load scales in the industry. “This has multiple advantages,” says Kernen. “Even the worst truck with overloading can drive on it without ramps. To drive onto a 17mm-thick platform is equivalent to a gradient of 5%. Imagine if the platform was twice as high!”

The low profile of the scale makes the leveling easier: the mats are small and the excavation is simple for semifixed use. Leveling is important in order to minimize measurement errors and it is mandatory in most countries.

Even with this minimal platform height, Haenni scales fulfill the high standards of the International Organization of Legal Metrology (OIML). This is mandatory for weight enforcement and is a sign of quality that approves the reliability of the instrument. The temperature range of such a product has to be from -10°C up to +40°C (14°F to 104°F), according to OIML R76.

“The scale must work in its specification in the cold winters of Canada, but also in the

hot summers of Oman. Therefore, we increased the range to -20°C to +60°C (-4°F to +140°F) as the standard range may not be sufficient. This extended temperature range and the thin platform makes Haenni’s wheel load scales unique worldwide,” explains Kernen.

Well-established base

Based on the well-established and reliable measurement platform of the WL 103, Haenni Instruments created the WL 108.

With its new graphic display with backlight and bigger numbers, reading the information is easier than ever. Furthermore, battery life is increased to 180 hours, with only two hours of charge time.

The new scale also features a wireless option that reduces installation time and eliminates the need for any connecting cables, which is crucial when the scale is used in particularly harsh environments. Weighing in at only 16.5kg (36.4lb) for a 10 metric ton (11.2-ton) or 15 metric ton (16.8-ton) scale, the measurement instrument is a lightweight of its kind and fulfills the provisions of any working union.

With the new WL 108 scale, Haenni’s development team aims to exceed the expectations of transportation professionals and make weight enforcement easier than ever. n

Haenni produces the thinnest, certifiable wheel-load scales on the market

Pure Precision.

S w iss Quality

www.haenni-scales.com n Robustness n High performance and endurance n For demanding professionals n Unique Swiss technology

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