Electricity + Control January 2019

round up

CONTROL SYSTEMS + AUTOMATION

EtherCATTerminals for mains monitoring, process control and power monitoring Energy management in machine operation and in the energy in- dustries creates a range of demands, starting with basic monitor- ing of the supply network and process control to high-end power monitoring. In response to these demands, Beckhoff has added four new EtherCAT I/O terminals to its existing product range, making a broader range of EtherCAT Terminals available. at 50 Hz. Four electrically isolated current measuring channels with freely adjustable measurement ranges for 100 mA, 1 A or 5 A, with a surge current capability of 60 A, are available.

Two further EtherCAT Terminal innovations have been designed for energy management in monitoring and maintenance applications: • As an economy version, the EL3423 three-phase power meas- urement terminal is intended for cost-sensitive energy manage- ment solutions, especially in IoT applications. The parameters that can be measured are energy, power and a mains quality fac- tor.These are recorded with an update interval that is adjustable from 10 s to 1 h. As a special feature, the measured parameters are available as average, minimum and maximum values. • The EL3483 three-phase mains monitoring terminal for volt- age, frequency and phase enables optimum monitoring of the power supply to a machine, which is particularly advanta- geous for systems that are sensitive to voltage variations. The functions include threshold value monitoring of the internal measured values, and setting of warning and error bits in the process image. Single-phase operation as a voltage, frequen- cy and phase monitor is also possible. Enquiries: Michelle Murphy.Tel. +27 (0) 11 795 2898 or email michellem@beckhoff.co.za

Together with the proven EL37x3 power monitoring oversam- pling terminals (and the associated TwinCAT Power Monitoring software library), the new EtherCATTerminals for energy manage- ment provide a comprehensive product portfolio that can be opti- mally adapted to the varied tasks found in a range of applications. Two of the new EtherCATTerminals are ideally suited for power measurement in process control applications: • As the new standard power measurement terminal, the EL3443 three-phase EtherCAT Terminal is universally suitable for all process control tasks. It offers numerous new functions such as mains monitoring functionality, precise determination of zero voltage crossing and harmonics analysis. In addition, it is also suitable for dc systems. • The EL3453 three-phase EtherCAT Terminal for measuring volt- ages up to 690Vac focuses on more demanding process control tasks. For this purpose, the terminal updates its process values with every half-wave, which corresponds to an interval of 10 ms

Ongoing evolution keeps Booyco PDS fit for purpose

A third zone can also be defined, in which the pedestrian’s presence will automatically trigger an electrical or mechanical interven- tion that reduces the vehicle’s speed to a crawl and even to a complete stop. Further enhancing the fit for purpose status of these technologies is the Booy- co Controller Interface to integrate all the deployed sensing systems; the company also has a range of test equipment for the systems and their applications, ensuring optimal uptime and safety impact. Enquiries: Anton Lourens.

In line with the Mine Health and Safety Act’s regulations on machinery and equip- ment, the onus is on mines to ensure that their proximity detection systems (PDSs) are ‘fit for purpose’ when it comes to pre- venting collisions between trackless mo- bile machines (TMMs) and pedestrians. In terms of the 2015 gazetted regula- tions, the employer must take ‘reasonably practicable measures’ to ensure that pe- destrians are prevented from being injured as a result of these collisions. The regula- tions also stipulate certain requirements regarding warning systems to pedestrians andTMM operators, and automatic means of retarding speed and braking on TMMs. This focus on compliance has kept Booyco Electronics at the forefront of technology development, innovating in- creasingly effective products to enhance safety and asset management on open- cast and underground mines. As a pio- neer in proximity detection, the company produces a range of solutions including interventions in vehicle operation to help prevent accidents and injury. The Booyco Electronics’ PDS warns pedestrians of an approaching vehicle and alerts the TMM operator that a pedestri-

an is within dangerous proximity of the vehicle. Using very low frequency (VLF) technology to generate a magnetic field around a vehicle proved to be a break- through in underground safety, as the VLF signal could propagate through the under- ground rock to identify hazards even be- fore they were visible to the pedestrian or operator. Both the pedestrians and drivers carry a personal communication tag which is activated when entering a warning zone around moving machinery. As mining regulations have raised the bar in terms of fit for purpose require- ments, so Booyco Electronics has evolved its PDS systems to provide feedback into TMM control systems.This is done through the creation of ‘zones’ within the magnetic field which trigger specific actions. The proven accuracy of the technology can define these zones precisely. A first zone of safety, for instance, may be 20 m from the moving vehicle, and is accurate to within 10 cm. A receiver and buzzer unit carried by the miner alerts them if they en- ter a dangerous area, even when out of sight of the vehicle operator, who is then warned if the pedestrian enters a second zone, closer to the vehicle.

Tel. +27 (0) 66 126 6926 or email anton@booyco-electronics.co.za

Using VLF technology underground, the Booyco PDS has proved its reliability.

Electricity + Control

JANUARY 2019

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