Contrinex's RFID systems keeps conveyor ‘on track’.

A manufacturer of bulk material-handling equipment trusts Contrinex's RFID (Radio Frequency Identification) technology to sense the position of a large rail-mounted conveyor operating in a dusty environment - Find out more at www.tiny.cc/CTX_RFID

A pair of read-write modules, mounted on the machine’s structure, interrogates a series of RFID tags, positioned at one-metre intervals along each travel rail. The control system identifies each tag individually and determines the exact position of the machine.

As the large mobile conveyor moves along parallel steel rails placed 100m apart at a speed of up to 2 m/sec (4.5 mph), it’s movement needs to be controlled accurately to avoid skew. Each time it passes an RFID tag, the read/write module reads its identification number at high speed which is transmitted via a PROFIBUS DP interface to the customer’s control system. A simple look-up table confirms the location of the tag and thus the position of the machine, allowing movement of both sides of the structure to be synchronized independently of the direction of travel.

Contrinex’s high-frequency RFID read/write modules and 30mm-diameter RFID transponder tags are ideal allowing for up to 10mm lateral movement, an IP67 rating, PBTP sensing faces and V2A stainless-steel housings, making them ideal for the demanding dusty environment. The ConIdent® passive transponders along the tracks require no power supply and have the same IP67 rating. This combination of read/write module and tags works over distances of up to 45mm and so was ideal for the application.

Key advantages:

• Uninterrupted production as positional identification is highly reliable
• No risk of skewing as movement of the large machine’s structure is synchronized
• Elimination of collision damage because of sensing distance up to 45mm