Telco sensors in conveyor belt monitoring
January 2019, Sensors & Transducers
Ordinary belt monitoring units can detect belt failure, but many require frequent maintenance for reliable operation. This is why Telco designed a system that ensures peace of mind for the plant owner.
The unit makes use of Telco infrared sensors to monitor the belt position at all times. These sensors are robust enough to handle the mining environment without problems as they are not affected by sunlight, water, dust or dirt. Units are available in various options depending on customer requirements. The most basic option will detect belt tear in the centre of the belt only. The next level detects belt tear and alignment. These two options can be supplied with an alarm indication only, or with voltage free contacts that can be incorporated into the PLC/scada system. The unit has been installed and tested in extremely harsh environments and has passed all tests. In one example, the sensor head was ground away by coal build-up, but it still worked without a problem.
The frame: is designed in a U-shape to fit around the conveyor. There are no sharp edges that can damage the conveyor and the powder coated steel can be supplied in various colours.
The sensors: two infrared transmitters and two infrared receivers are placed one on each side of the conveyor. These can be doubled up for even more protection if required. The amplifier is not situated on the transmitters or receivers but in a separate standalone unit, which can provide up to a 10 second delay to eliminate nuisance trips.
Failsafe: the system is designed to be failsafe, meaning that a power or system failure will also stop the conveyor.
Power supply: the system can be supplied with 24 VDC or 24 /110/220 VAC – contacts are rated up to 10 A.
Protection against the elements: the amplifier and relays are fitted inside an IP65 box. The frame and sensors are weather proof as described.
System integration: the system has voltage free contacts that can be used to connect to a PLC, which can then also be connected via a communication network to a scada system.
Maintenance: The system can be tested by manually disconnecting the transmitters and holding them in line with the receivers.
For more information contact Gail Norton Instrumentation Agencies, +27 31 701 4861, firstname.lastname@example.org, www.gailnortoninstrumentation.co.za