The USB to RS485 media converter is certified IS for associated apparatus category ‘ia’ Group I / IIC, for a T4 temperature class. This means when the unit is installed outside a hazardous area, it is now possible to communicate directly to IS serial devices installed in hazardous areas without the unit having to be in an explosion-proof enclosure. Only when the unit is installed in a hazardous area must it be contained in such an enclosure. There is no need for external serial isolators or barriers, or even additional IS power supply units.

The unit is powered directly from the USB port on a PC. The serial communication is able to operate up to distances of 1200 metres (cable dependant). Easy-to-understand LEDs indicate the power status and TX/RX transmission on the serial communication lines, clearly indicating if there is communication on the line.

All Booyco Electronics IS products are certified by an independent Certified Testing Laboratory endorsed by SANAS, in compliance with national IS standards and have batch approval certificates.

An open pit diamond mine in Limpopo has also ordered the DSS from Booyco after successful demonstration on a Cat 793 haul truck. Booyco Electronic’s Charl van den Berg says the mine had been testing other fatigue monitoring equipment, and purchased DSS after it successfully showcased.

Booyco Electronics was appointed sole southern African distributor for the DSS product line in 2009 by Australian-based Seeing Machine. The DSS, originally developed in Australia, is a fully automatic driver awareness and fatigue warning system that utilises a miniature sensor mounted on the dashboard of a vehicle. It provides feedback on fatigue and other factors in order to boost operational safety.

Van den Berg says Booyco has conducted its own field testing and introduced adaptations to suit local conditions. The company has also obtained approval from industry unions, who recognise the increased driver safety implications of the system.

The DSS is also currently being trialled at Vedanta Metals’ Skorpion Zinc mine in Namibia on Cat 777 haul trucks.

“We trialled the DSS over 361 combined driving hours and the system has provided Skorpion with valuable data about the extent and effects of driver fatigue at its operation,” he says. “Feedback from the safety manager has been very positive. We are also conducting trials at a cement mine in the Northern Cape on a Mercedes Actros truck, at a mine in KwaZulu-Natal on a Western Star haul truck and at a uranium mine in Namibia on a haul truck.

“We are receiving an ever-increasing number of enquiries about the DSS from the mining industry, but there is also a promising amount of interest from the long haul transport sector,” he says. “Driver fatigue poses not only a serious safety issue, with its associated massive cost implications, but can also lead to damage and loss of valuable vehicles and cargo.”

The DSS is customised to suit each unique customer application. It can be configured to provide instant audio feedback to drivers when fatigue events are detected, modulated in such a way that a driver cannot abuse the system.

Unlike other systems on the market, the DSS does not require the driver to wear a headpiece or special glasses and is totally non-obtrusive. The system comprises a number of elements, including a dashboard-mounted sensor, which “sees” the driver’s face and measures eyelid closure and the orientation of the driver’s head and upper torso.

“Eyelid closure information is processed to determine the level of driver fatigue, while tracking head movement makes it possible to monitor driver distraction. If the driver has not been focused on the roadway ahead for a period, the DSS-IVS (In Vehicle System) detects this event and generates instant in-cab alarms, including audio alerts and seat vibration feedback,” Van den Berg explains. “Once installed in the vehicle, the DSS is fully automatic. There is no calibration procedure for each new driver.”

The DSS allows for integration of data into a fleet management system, allowing management to create a fatigue index, not only for individual drivers, but also for specific routes the vehicles may take. In addition, the data can be harnessed to change driver behaviour, for instance, through the introduction of more frequent, but shorter, breaks during a given shift.

Van den Berg relates that in one case the system helped to identify that the cause of severe driver fatigue in a specific vehicle was attributable to toxic emissions entering the cab. In another case, the fatigue patterns of a specific driver led to the diagnosis of the unknown existence of diabetes.

The DSS can be linked to an on-site control room, where operators can monitor driver activity in real time. In the event of a fatigue-related alarm, the operator can intervene and take proactive measures to address the problem, even removing the driver from the shift in extreme cases.

Intrinsic safety (IS) is a protection technique for safe operation of electronic equipment in explosive atmospheres and under irregular operating conditions. The concept was developed for safe operation of process control instrumentation in hazardous areas. As a discipline, it is an application of inherent safety in instrumentation. The theory behind intrinsic safety is to ensure that the available electrical and thermal energy in the system is always low enough that ignition of the hazardous atmosphere cannot occur.

“As technology advances important communication hardware, such as the standard serial communication port, is now a specialised after market add-on to portable and desktop model computers,” Booyco Electronic’s Jaco du Plessis, explains. “This has made it increasingly difficult to interface with serial devices — calling for the installation of different kinds of media converters coupled together for successful communication to serial devices such as PLCs and belt drives.

“When it comes to IS applications, this task appears almost impossible. For IS loops to be approved certified serial isolators, IS barriers and IS power supply units must be used in the installation.  .

“To address these requirements, Booyco Electronics has developed an USB to RS485 media converter, certified IS for associated apparatus category ‘ia’ Group I / IIC, for a T4 temperature class,” Du Plessis says. “This means when the unit is installed outside a hazardous area, it is now possible to communicate directly to IS serial devices installed in hazardous areas without the unit having to be in an explosion proof enclosure. Only when the unit is installed in a hazardous area must it be contained in an explosion proof enclosure. There is no need for external serial isolators or barriers, or even additional IS power supply units.”

The unit is powered directly from the USB port on a PC. The serial communication is able to operate up to distances of 1200 metres (cable dependant). Easy-to-understand LEDs indicate the power status and TX/RX transmission on the serial communication lines, clearly indicating if there is communication on the line.

“Booyco Electronics offers the market the most advanced IS solutions,” Du Plessis says. “Our products are certified by an independent Certified Testing Laboratory endorsed by SANAS, in compliance with national IS standards.”

Booyco Electronic’s IS RS485 Barrier serves as an isolation barrier on a serial communication bus between a non-hazardous and hazardous area in a mine or plant environment. The unit, approved for Group I and IIC, is powered from a 12 to 24 Volt DC power supply. Any RS485 based communication can be isolated by this unit, as it is protocol independent. The barrier simply relays the data strings it receives. If the unit is destined for installation in a hazardous area, it must be installed in an explosion proof enclosure.

“Only low voltages and currents should be allowed to enter the hazardous area and all electric supply and signal wires must be protected by safety barriers, such as the Booyco IS RS485 unit,” Du Plessis says. “An alternative type of barrier known as a galvanic isolation barrier may also be used. In normal uses, electrical equipment often creates internal tiny sparks in switches, motor brushes, connectors and in other places. Sparks like this can ignite flammable substances present in air and must be eliminated at all costs from hazardous zones in the underground mining environment.”

PSU and UPS
The company’s IS offering includes an active high power, 2 Amp at 12 V IS Power Supply Unit (IS PSU) suitable for providing items in hazardous areas with various DC IS power. The IS PSU includes overload protection and isolates the load from the power supply when an overload occurs.

The use of alternative battery technology has produced Booyco Electronics’ IS uninterruptable power supply (UPS) which offers reliable performance under even the harshest operating conditions. The IS UPS is locally manufactured under stringent quality management systems and meets all the statutory regulations pertaining to IS equipment. Du Plessis comments that while there are many UPS systems available on the market, few of these are intrinsically safe and suitable for underground use.

The Booyco IS UPS is able to deliver 2 Amp at 12 Volt for extended distances up to 2 km. To cater for individual application requirements, the units can be supplied in multiple outputs. The various models available deliver backup power up to 80 Amps per hour. The IS UPS is suitable for a spectrum of critical applications, including maintaining communications systems and gas detection systems.

“An important aspect of intrinsic safety is controlling abnormal small component temperatures,” he comments. “Under certain fault conditions — such as an internal short inside a semiconductor device — the temperature of a component case can rise to a much higher level than in normal use. Safeguards such as current limiting by resistors and fuses must be employed to ensure that under no circumstances can a component reach a temperature that could cause auto-ignition of a combustible atmosphere.”

“No single field device or wiring is intrinsically safe by itself, except for hermetically sealed battery operated, self contained devices,” Du Plessis says, “but is intrinsically safe only when employed in a properly designed IS system.  All items of equipment we manufacture for underground gas detection systems are compliant with SANAS regulations and we have batch approval certificates for all these products. And, since we produce the full range of IS equipment, at Booyco we are also able to conduct on-site IS loop certification for our customers.

“These capabilities give us full confidence in the products we produce to sustain and improve mine safety.”

Tamping is a legal requirement to contain and distribute explosive energy in the blast hole, reducing the risk of fire hazard. It maximises the effect of an explosion, concentrating it into the rock instead of allowing expanding gases to escape through the blast hole.

There are several types of tamping systems available. Clay plugs tamped down with a wooden rod are most commonly used, but when a misfire occurs they are notoriously difficult to remove. This is not only time consuming, but costly. The alternative polymeric foam composition for tamping is also an expensive option.

Manufactured from fire-retardant and anti-static polypropylene, the lightweight and portable Advanced Tamping Device is unaffected by wet holes and is fully recoverable and reusable in the event of a misfire. It is impervious to all working temperatures and is ideal for slow-release propellant blasting.

This innovative tamping device reduces wastage, saving up to 25% on explosive costs. Use of the Advanced Tamping Device improves fragmentation, reduces dust and rock, labour, transport and electricity and improves surface crusher efficiency. It also has an unlimited shelf life.

The Advanced Tamping Device has been tested locally and the results verified that the blasted rock contained less fines and that hanging and sidewall control was satisfactory.

Booyco Electronics MD Anton Lourens says it is crucial for mines and other organisations to have IS UPS systems in place in the underground environment, especially with the uncertainty of power supply in Southern Africa.

“The Booyco IS UPS is locally manufactured under stringent quality management systems and meets all statutory regulations pertaining to IS equipment,” he adds.

While there are many UPS systems available on the market, few of these are IS and suitable for underground use. Booyco Electronics identified the need for such a UPS and this is a natural extension of the company’s IS high-current power supply range of equipment.

“The company made use of alternative technologies, which were combined to provide, what we believe to be, a unique and affordable solution for underground applications,” says Lourens.

A conventional UPS makes use of alternating current (ac) voltage input that cannot be made IS because of the nature of ac voltage and the constraints of IS specification. Further, the types of battery used for backup when power supply to the unit fails, are normally lead-acid or lithium-ion. These batteries are not immune to operational incidents, such as short circuits of the battery’s pole, which results in the battery heating up and ultimately exploding.

Also, the chemical makeup of the battery includes dangerous chemicals such as acid that will damage any material it comes into contact with and can also release flammable and poisonous gases.

Owing to the dangers that normal batteries present, a solution had to be found to eliminate or reduce these dangers.  “Usually, the only option is to install the batteries into an explosion-proof (EP) enclosure and fill it with sand. However, this causes significant difficulties as the panel becomes extremely heavy and expensive,” explains Lourens.

He adds that, when repairs or work on the panel need to take place, all the sand needs to be removed and replaced afterwards, being highly maintenance intensive.

Booyco noticed that this seemed too problematic to be a solution to creating an IS power supply unit (PSU) and UPS applications, so the company undertook research and found alternative solutions.

The company manufactured an IS PSU that provides a direct current output of 12 V or 24 V.  The IS PSU is installed in an EP enclosure as specified under IS requirements, which state any device that is coupled to a non-IS input must be installed in an EP enclosure.

“Our UPS uses a unique battery unit that eliminates the dangers of conventional batteries. The unit is installed in its own enclosure with additional components and is separately approved to IS specifications,” says Lourens.

He adds that combining the IS battery with the IS PSU eliminates all the dangers of a conventional UPS. Because of this, the rule to install the components in an EP enclosure is not applicable and sand is not required, which means the unit does not have a heavy enclosure, and makes it fairly inexpensive.

“We specifically chose not to place our UPS in an EP enclosure or to use sand as an additional layer of protection. This application required its own solution and not simply a modification of a conventional UPS,” states Lourens.

The Booyco IS UPS is able to deliver 2 A at 12 V or 1Amp at 24 V, or a combination of both for extended periods of time, and, to cater for individual application requirements, the units can be supplied in multiple outputs.

The various models available deliver power up to 80 A/h and are suitable for a number of critical applications including maintaining communications systems and fire detection systems.

Safety of underground mine transport and machinery is one of the four focus areas of a dedicated Mining Industry Occupational Safety and Health (MOSH) team instituted by the Chamber of Mines of South Africa to drive the adoption of leading safety practices throughout the industry. Under this banner, a Transport and Machinery Adoption Team is working on developing processes which will speed up the widespread adoption of safe practices in this particular arena.

Electronic safety equipment specialist Booyco Electronics is the leading supplier of collision warning systems to the South African mining industry. Managing director of the company, Anton Lourens says that to date, however, industry uptake of proximity detection technology has been relatively slow. Although Booyco Electronics has equipped more than 25 000 mines with collision warning systems since 2006, this represents less than 10% of the market that will soon be required by law to install this type of technology.

Lourens says both collision warning systems and collision avoidance systems are required in the mining industry, depending on the nature of the application. A collision warning system consists of a sensor that detects the presence of an object, an interface that provides an audible and/or visual alarm to the equipment operator and wiring between the two. These systems warn both vehicle operators and pedestrians of potential danger. Sensor technologies include ultrasonic echo detection, infrared reflection, radar (radio detection and ranging), video cameras and radio frequency identification (RFID) systems.

A collision avoidance system is a system of sensors that is placed within a vehicle to detect potential collisions with objects or personnel. This technology is able to interact with the mobile equipment or vehicle’s brakes and bring it rapidly to a complete stop.

“The coal industry is starting to install collision avoidance systems,” Lourens says, “but collision warning systems are more appropriate for hard rock mines, with their steeply angled stopes. Within this technology, experts agree that very low frequency (VLF) systems are best for warning pedestrians who work near moving machinery, while ultra-high frequency (UHF) signalling is more suitable for high speed and track-bound equipment.”

Lourens believes, therefore, that mining companies that are about to install this kind of technology underground for the first time should do extensive research before deciding which system to purchase. This is particularly advisable at the moment, since he predicts it is likely that new non-specialist companies will emerge in the current climate to market collision-related technology to the mining industry, in a technology maturing market.

“Protecting personnel and equipment is a critical focus area in the industry,” he comments. “Proximity detection technology is also capital intensive, so when investigating which system would be most suitable for a given application, mining companies should look for a system that has a proven track record and which is well supported by the supplier in terms of technical support, spares, stockholding, operator training and change management. Suppliers should also be seen to be reinvesting into continuous product development and enhancement.

“Price is always a factor, but we advise companies to evaluate the total cost of ownership, rather than the initial capital outlay.”

Booyco Electronics markets a range of CWS (Collision Warning System) products, custom adapted for use in both the surface and underground mining environment. The company is focusing on supplying reliable safety systems to warn of the possibility of collisions between vehicles and pedestrians, and vehicles with vehicles. Research in this arena has led to strategic alliances with the innovative companies, VAK Technical Solutions and Selectronic Funk-und Sicherheitstechnik GmbH, which ensure that Booyco Electronics is able to continuously develop solutions to meet customer-specific requirements in the mining industry.

One of the company’s early successes was with the CWS500U collision warning system, out of which its CWS800 and CWS800 PLUS have been developed. These innovative systems includes vehicle-to-vehicle detection as part of a single underground and surface solution for both close proximity (pedestrians) and longer range (vehicle) warning. The added benefits of the system could include, among others, interlocking with third party equipment, such as ventilation doors and robot systems.

The locally developed sensors are being hailed as the most innovative alternative on the market today, with many unique design features that address the shortcomings of current sensor instrumentation. Anton Lourens, managing director of Booyco Electronics, says many of these features were developed as a response to market demand.

“During the design phase we did a lot of research and identified several factors which users identified as problematic with the current technology,” he says. “The instruments we have come up with have actually exceeded our own expectations and we are delighted to be able to offer such an advanced solution to mine environmental personnel.”

The Booyco Electronics ESI Sensor range is available both as a fixed installation — where gas emissions need to be monitored at specific locations, the Smart Sensor — and in a portable handheld format, dubbed the Sentient.

The fixed unit features a localised display of sensor information and can measure 15 different gases from a single controller, typically including oxygen (O2), carbon dioxide (CO2), flammable gases such as methane (CH4) and toxic gases such as carbon monoxide (CO). Average response time is less than 35 seconds, depending on flow rate. The Smart Sensor’s controller can also accommodate other sensors with analogue outputs, such as air velocity sensors or smoke detectors.

“A unique feature of the Smart Sensor is its modular design that makes for ease of repair and calibration,” Lourens says. “If a sensor fails, only this sensor unit need be removed — there is no need to open the main enclosure to replace a new sensor. Similarly, when the sensor calibration expires, the sensors can be replaced in situ with new pre-calibrated sensors.”

The Smart Sensor unit can easily be connected to a fire detection system with reporting and display on SCADA.

Lourens says ingress protection on the Smart Sensor exceeds IP56 and the instrument carries the following approvals: SANS IEC 60079 Part 0:2005; SANS IEC 60079 Part 11: 2007 and IEC 60529 (IP code).  The unit measures 265 mm by 150 mm by 60 mm and weighs in at 1.8 kg.

The Sentient
The IP68 rated Sentient handheld version is the most sophisticated instrument of its kind available on the market. Able to accommodate up to three “plug and play” sensors, typically CH4, CO and O2. The inner mechanism of this device is completely sealed, so although sensor units are regularly removed and replaced, there is no opportunity for moisture to penetrate the sensitive working parts. The low maintenance Sentient also has no buttons — instead an innovative “tap” sensor ensures that the instrument remains watertight.

Amongst the unique features of this device is “drop protection” which automatically switches the sensor off as a protective measure if the instrument is dropped, thereby significantly increasing sensor life.

Both the fixed and handheld units have been certified as EXia T4 Intrinsically Safe.

A proactive and focused marketing strategy, combined with solid technical support within close proximity of the various mining nodes, has successfully positioned Booyco Electronics as an influential and service orientated supplier.

CWS
The flagship product, and one which has received overwhelming mining industry support, is the range of CWS (Collision Warning System) products, custom-adapted for use in both the surface and underground mining environment.

“With safety top of mind in the mining industry today, an urgent need for reliable safety systems to warn of the possibility of collisions between vehicles and pedestrians, and vehicles with vehicles was identified,” Anton Lourens, managing director of Booyco Electronics, says. “Our strategic alliances with the innovative companies, VAK Technical Solutions and Selectronic Funk-und Sicherheitstechnik GmbH, ensure that we are able to develop solutions to meet customer-specific requirements within our chosen field.”

One of the company’s early successes is the CWS800U collision warning system, out of which the CWS800 PLUS has been developed. This innovative system includes vehicle-to-vehicle detection as part of a single solution for both close proximity (pedestrians) and longer range (vehicle) warning. The added benefits of the system include asset locating solutions and interlocking with third party equipment, i.e. ventilation doors, robot systems etc.

Telemetry and control equipment
Booyco Electronics’ REMCON product range has been developed over several years and is primarily customer driven. These products have found application in both the surface and underground environment.

Centralised blasting systems
Both the basic C3 and latest developed NECST centralised blasting systems offer flexible and unique centralised blasting solutions that can be executed safely from the surface. The Centralised Blasting Systems have numerous safety features that ensure no untimely or unwanted blast can occur. The systems are available with battery back-up and remain operational on sub-levels in the event of a network backbone malfunction.

Advanced Tamping Device
Booyco Electronics’ Advanced Tamping Device (ATD), a patented locally developed product, is manufactured from fire-retardant and anti-static polypropylene. Its primary advantages include that it is unaffected by wet holes, is fully recoverable and reusable in the event of a misfire, is impervious to all working temperatures and is ideal for slow-release propellant blasting.

“Trapped miner locator”
The “Trapped Miner Locator” system has been met with positive feedback from deep mines. Miners’ lamps are fitted with a VLF transmitter (tag) that has pronounced through-rock penetration capabilities. Search teams are equipped with a battery operated VLF receiver used to screen the rockfalls ahead of them. The VLF technology enables the device to read through rock up to 30 metres ahead and give a fairly accurate indication (in metres) of how far the miner’s tag is located — or if there is no tag in the vicinity.

Driver State Sensor
The Driver State Sensor (DSS) System is a fully automatic driver awareness and fatigue warning system that utilises a miniature sensor mounted on the dashboard of a vehicle. The system provides feedback on fatigue and other factors to increase operational safety. In addition to in-cab feedback, the DSS can be integrated into fleet management.

ESI Sensor range
The ESI Sensor range is available both as a fixed installation — where gas emissions need to be monitored at specific locations, the Smart Sensor — and in a portable handheld format, dubbed the Sentient. The fixed unit features a localised display of sensor information and can measure 15 different gases from a single controller. Average response time is less than 35 seconds, depending on flow rate. The IP68 rated Sentient handheld version is the most sophisticated instrument of its kind available on the market, able to accommodate up to three “plug and play” sensors.

According to Anton Lourens, managing director of Booyco Electronics, the Sentient handheld instrument is simple to use, yet extremely reliable. The inner mechanism of this device is completely sealed, so although sensor units are regularly removed and replaced, there is no opportunity for moisture to penetrate the sensitive working parts.

Rated to IP68, the low maintenance Sentient has no buttons. Instead, the unit features an innovative “tap” sensor which ensures that the instrument remains watertight at all times.

Amongst the unique features of this device is “drop protection” which automatically switches the sensor off as a protective measure if the instrument is dropped, thereby significantly increasing sensor life. The unit has been certified as EXia T4 Intrinsically Safe, and complies with relevant SANS 1515 requirements.

The solution selected is the Booyco Electronics Collision Warning System. This is a first for Murray & Roberts Cementation, reflecting the proactive stance the company has adopted towards safety issues, and it represents a significant investment in the interests of safety.

“Visibility underground always presents challenges,” Lane explains. “Both the machines themselves as well as the nature of the underground layout restrict visibility for machine operators and pedestrians. Collisions between vehicles as well as with pedestrians are a constant risk, so we looked for a solution to provide complete two-way communication between vehicles and pedestrians as well as from vehicle to vehicle. The answer was Booyco’s CWS 800 Plus which offers this vehicle-to-vehicle collision detection capability in addition to the traditional pedestrian alert.”

The CWS 800 Plus allows both detection of people in close proximity to vehicles and longer range vehicle-to-vehicle detection. Previously, two separate technology systems were required: close proximity, low frequency technology to detect people close to vehicles and a separate and alternate system for vehicle-to-vehicle detection. This technological configuration resulted in greater cost to the customer.

“The combination is a first in South Africa,” Lane continues. “The technology now incorporates both UHF RFID (Ultra High Frequency Radio Frequency Identification) and VLF (Very Low Frequency) capabilities. “VLF is the only reliable technology for collision warning underground, providing through-rock penetration so that pedestrians are alerted to oncoming vehicles even around rock walls and corners.”

Every pedestrian is fitted with a VLF tag which is tested before the miner goes underground. “His ID number is recorded, so at all times, there is an accurate determination of who is underground,” he says.

“An added advantage of the CWS 800 Plus is that its parameters can be adjusted from one to 12 metres for pedestrians using VLF and up to 50 metres for vehicle-to-vehicle alerts using UHF. A flashing light and buzzer warn the pedestrian of oncoming vehicles whereas a visible and audible alarm in the vehicle cab caution the operator to stop immediately.”

Lane explains that Murray & Roberts Cementation has established a five metre perimeter for its CWS units since the trackless machines used are slow moving with short stopping distances. “This provides 10 metres between vehicles which is an accepted industry standard,” he adds.

Other functionalities include remote activation of ventilation doors by vehicles which adds further to safety benefits. In addition to the inherent advantages of VLF technology, the system incorporates very intelligent IP to ensure that the UHF is reliable and accurate. A further advantage is that the system is not adversely affected by surrounding equipment or the presence of ore bodies.

“The system, which is simple to implement, is being rolled out in a phased approach to our contracts,” Lane says. “We have already installed units at Wessels Mine and Lonmin’s Pandora Mine and will shortly install units at Kroondal Shaft Banbanani, Anglo Coal Goedehoop and BHP’s Khutala. Extensive training is provided to all miners as well.

“I have little doubt that this collision warning system will eventually become a prerequisite in any mining operation.”