NB4200 in wood chips storage silo

The Challenge

A woodworker in Sweden needed a suitable level measuring system for his large storage silos for wood shavings. The sensors are exposed to large temperature differences depending on the season and weather conditions. Within the process is a high dust development. Thus, dust can adhere to the sensor and affect the function. The surface of the wood chip to be measured has steep angle of repose and is very absorbent. The measuring range is about 15-20m.

Our Solution

The customer decided for an electromechanical measuring systems. The NB4200 was used. It provides for the electronic evaluation a 4-20mA signal, counting pulses or a Modbus RTU interface. A thermostat-controlled heating system has been integrated for stable temperatures in the housing. A tape cleaner, which is active during the measurement, helps against the dust adhering to the measuring tape. The sensor NB4200 has a measuring range of 30m and covers the requirements in these silos. The very high lifetime of the tape with 500,000 measuring cycles even when the silo is empty makes the NB almost maintenance-free in this application.