Telemetry
Telemetry remote control and monitoring can significantly enhance the functionality of a leaky feeder radio system, however the leaky feeder system must be of sufficient quality to handle the data requirements. Typical uses and advantages of telemetry to streamline the operation of equipment underground include:
- Energy efficiency (electric power savings) through the ability to turn fans off, or operate at a reduced speed, when not required or where ventilation flow can be adjusted to suit requirements.
- Short term control of fans; such as before, during and after blasting.
- Remote monitoring of equipment, and subsequent remote control of that equipment (or other equipment) to manage the monitored situation (e.g. turning on a pump when water levels in an underground storage dam reach a pre-set limit). This monitoring and control can be partly manually operated or automated (e.g. through interface to SCADA packages such as Citect) .
- Telemetry can reduce the time and complexity in setting up control systems when equipment is re-located (e.g. when a fan is re-located). Once power is provided to the location control is immediately available, via the radio link to the leaky feeder system. The quality of the leaky feeder system allows this direct radio link to the leaky feeder system to be established easily, lower quality leaky feeder installation will require significant hard wiring and running of cables to establish the link (this somewhat defeats the reasoning behind using telemetry in the first place, i.e. its flexibility - see additional comments below).
MST designs & supplies complete telemetry systems for operating through a mine's leaky feeder radio system. If a VDV Leaky Feeder System already in place, than the available bandwidth is more than enough to support a telemetry based control system. If other types of leaky feeder systems are in use than an audit of that system's performance would be required to ensure it can handle the data requirements of a telemetry interface. The picture to the right shows a typical fan starter unit built up for a mine. "Soft" start of the fan can be achieved with a timer or with the pulsed startup programmed into the telemetry logic.
Mine Site Technologies has built up considerable experience in telemetry installations at many mines. The picture to the left shows a Miri telemetry unit, which we program with the relevant ladder logic to control the various inputs and outputs. For example, telemetry systems can be designed and installed on typical single or dual fan starters to undertake straight forward stop-start functions as well as feed back on fan faults, individual stage running or stopped, etc (basically any digital input or output). Analogue inputs, such as temperature, can be incorporated where required.
MST's telemetry systems have the distinct advantage over some other, so called telemetry systems, by providing a true radio link between the device being monitored/controlled and the leak coax antenna. This means it does not rely on any cable links or some type of in-line 'telemetry unit' being inserted into the leaky feeder antenna. The flexibility and advantages that the elimination of hard wiring give cannot be over stressed. Any additional hard wiring, or insertion of additional hardware, into the leaky feeder network, complicates the system and compromises the integrity of the entire leaky feeder back bone. This additional hardware limits the flexibility of the installation, particularly with equipment like fans, that are moved regularly. By using only a radio link to the leaky coax antenna, MST's telemetry allows the unit to be ready for use as soon as power is connected.
If a VDV System is in use (either Series 1 or Infinity Series) than the performance of the system, particularly bandwidth, allows the easy implementation of telemetry. As mentioned, if another type of leaky feeder system is in use, than an audit of that system would need to be undertaken to assess its performance (this gives us actual performance, not just specifications written down in a Manual).
Should you have any questions in regard to telemetry or wish to discuss a particular application please contact us and one of our engineers will assess your request and respond.