Sensors & Transducers


Underground methane monitoring

October 2014 Sensors & Transducers

Blades on a large heavy metal circular ball spin at a high speed crushing rock and, possibly, releasing dangerous levels of invisible methane gas. Pressure and speed are adjusted by the operator controlling the machine with joysticks and buttons, but this is not your next-generation gaming console.

This is reality 61 metres below ground in a coal mine. The machine: a roadheader.

The roadheader is equipped with tools that grab the rocks and place them on a conveyor before they are sent out of the mine for processing, ultimately to be burned to produce electricity, cement or even steel.

The danger of methane

Although the cliché ‘safety first’ is used in just about every work environment, it has to be the standard in a coal mine where people are working hundreds of metres underground in a hazardous environment.

KFG Electric Systems in Poland is a company that knows this. KFG recently engineered and installed a modern underground coal mining control system that is designed to be used anywhere in Europe with the latest safety features desired by the major mining companies, including protection against methane.

Methane is a big concern for coal miners as it releases naturally during coal extraction. For years, canaries were used in mines to detect high methane levels as they could not survive in slightly lower than the dangerous levels for humans. When the bird stopped chirping, the miners knew to flee. For the last four decades, thanks to modern detectors worn by every miner, methane is detected without killing any birds.

The problem

The controls enclosure that is on the rear of the roadheader measures 1700x700x600 mm with a weight of 1200 kg, making it rock-solid for underground mining applications. It is equipped with a safety Rockwell Automation Compact GuardLogix 43S, a Point IO safety adaptor and a regular Point IO adaptor. A safety PAC is used for safety specific instructions, security and safety I/O.

KFG needed to communicate from the Rockwell Automation system that natively speaks EtherNet/IP to protection relays, EX IOs and other devices that communicate using Modbus.

The solution

The system uses several specialised Modbus devices from different vendors and because of this, it needed a gateway with multiple ports. ProSoft Technology’s gateway has four Modbus ports and is fast with up to 4000 words in 5 ms.

KFG chose ProSoft Technology’s EtherNet/IP to Modbus Gateway to communicate from the controller to the protection relays and other remote Modbus devices. “We didn’t want to be beta testers and use a device made by a one-person company,” Marcin Ptaszny CEO of KFG Electric Systems said. “It was key to have long term support and availability of the device.”

A proven solution was required and hence ProSoft Technology was chosen. A protection relay senses when there could be trouble and transmits the information to the PAC which shuts off the system.

Port 1 of the gateway is connected to an RTU master and communicates with over current protectors. Port 2 is connected to a RTU slave which is used for the remote radio control system that allows the miner to control the roadheader from a safe distance. Port 3 is connected to an RTU master and explosion safe distributed I/O system. Port 4 is connected to an RTU slave and communicates to a surface scada system.

The ProSoft Technology EtherNet/IP to Modbus gateway was easy to configure, diagnose and implement. “This is why the customer loves the add-on profile and add-on instruction we delivered,” said Ptaszny. “They are pleased with the implementation of EtherNet/IP to Modbus gateway, specifically the I/O connection allowing really fast data exchange with the I/Os and the remote joystick in the roadheader.”

Mining is the kind of market which does not implement technological changes quickly. KFG is one of the first companies in the world designing new mining systems this way, using safety I/O and a GuardLogix safety controller communicating with numerous protection relays and EX IOs.

For more information contact Bob Petrie, Throughput Technologies, +27 (0)11 705 2497, info@throughput.co.za, www.throughput.co.za



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Precision acoustic imagers
Comtest Sensors & Transducers
To help users identify and localise ‘mechanical areas of interest’ within short timeframes, Comtest has added a unique new feature to Fluke’s ii910 precision acoustic imagers.

Read more...
Efficiency and precision with IO-Link sensors
RS South Africa Sensors & Transducers
RS South Africa has its own brand known as RS PRO, which offers a choice of over 88 000 products across all industries and technologies. The guaranteed quality and breadth of this range make RS PRO the smart choice for your business.

Read more...
Smart alternative for float switches
ifm - South Africa Sensors & Transducers
With the LI level sensor, you can reliably detect leakages and point levels on a permanent basis. The capacitive measuring system has no moving parts. Malfunction or maintenance issues due to deposits on the mechanical parts are therefore eliminated.

Read more...
Optical fork sensor series
Gail Norton Instrumentation Sensors & Transducers
The OFS series consists of self-contained optical fork sensors that are housed in a durable, U-shaped aluminum housing, which operates in through-beam mode.

Read more...
In-line process transmitter to optimise sterile processes
WIKA Instruments Sensors & Transducers
The new model DMSU22SA in-line process transmitter from WIKA helps to optimise sterile processes in the pharmaceutical and food industries, with less energy consumption, less cleaning effort ,and more safety.

Read more...
Automated clean-in-place
Endress+Hauser South Africa Sensors & Transducers
A clean-in-place (CIP) process is integral to a food and beverage producer’s responsibility to deliver safe, high-quality products to consumers. However, as industries worldwide shift focus towards sustainability, CIP procedures face new challenges.

Read more...
Signal conditioning is the protective armour between plant and field
Omniflex Remote Monitoring Specialists Sensors & Transducers
Measurement and control of physical properties are the foundation of all critical industrial technologies. Ian Loudon, international sales and marketing manager at remote monitoring specialist, Omniflex explains the challenges of industrial signal conditioning and the importance of safety engineering.

Read more...
Precise detection of complex rotational movements
Beckhoff Automation Sensors & Transducers
The EP3751-0260 EtherCAT Box module by Beckhoff connects an acceleration sensor with an inertial measurement unit - a gyroscope. This provides accurate detection of acceleration and rotational motion in addition to shock, vibration and tilt measurement, both as preprocessed values and as raw sensor data.

Read more...
OEM pressure sensor for mobile working machines
WIKA Instruments Sensors & Transducers
The MH-4-CAN, based on the MH-4, is a powerful, reliable and extremely resilient pressure sensor for mobile working machines.

Read more...
T-slot cylinder sensors with IO-Link
Sensors & Transducers
ifm’s IO-Link sensor, with two configurable hardware outputs, will upgrade your machine in no time.

Read more...