November 2001Maintenance, Test & Measurement, Calibration
The EPIC noncontact position transmitter represented a significant departure from previous attempts to reliably measure the position of rotary control valves. As opposed to conventional devices, couplers are not utilised. A magnetic proximity module, attached to the actuator output shaft is the only 'moving' part in the transmitter. Sensing is performed totally by noncontacting means, based upon characterisation of flux strength as a function of axial position.
A solid-state sensor is employed, whose output is a function of both flux density and excitation voltage. That property allows the use of an internal bridge circuit for accurate zero adjustment, where one arm of the bridge is comprised of the sensor, and the other comprised of a resistive divider for zero reference.
Transmitter output is 4-20 mA, two-wire, with compliance voltage ranging from 14,5 to 35 V. Output updating takes place 20 times per second, allowing use of the transmitter for applications not possible with transmitters of other types. The inherent reliability of the transmitter permits use of advanced control strategies, where knowledge of valve position can be used in predictive and other algorithms.
Precision, control and performance in regulators and control valves Valve & Automation
Valves, Actuators & Pump Control
Cashco has long been a trusted name in industrial control solutions, offering a broad range of regulators and control valves designed to meet the rigorous demands of various industries. There are two key Cashco product lines, its regulators and the Ranger QCT control valve.
Read more...WearCheck leads the way in condition monitoring Wearcheck
Maintenance, Test & Measurement, Calibration
Minimising maintenance costs of mining and power-generating machinery and maximising its operational efficiency – these goals form the foundation of the proactive/preventive maintenance services provided by the expert technicians at condition monitoring specialist, WearCheck.
Read more...Collect data three times faster SKF South Africa
Maintenance, Test & Measurement, Calibration
SKF has extended its renowned Microlog Analyzer family of data collection devices with the addition of the Microlog Analyzer dBX. Currently SKF’s most powerful diagnostic tool, this cutting-edge device redefines diagnostic capabilities, enabling users to take measurements three times faster than its predecessor.
Read more...Valve & Automation is exclusive agent for Cashco Valve & Automation
News
Valve specialist, Valve & Automation, supplies total valve and control solutions to key process industries throughout southern Africa. The company has now been appointed as the exclusive agent for US company, Cashco for the supply of control valves, regulators, tank equipment and flame arrestors.
Read more...Integrated liners for the mining industry
Maintenance, Test & Measurement, Calibration
Multotec has developed a range of composite integrated mill liners in response to the needs of local and international mining clients.
Read more...The criticality of maintenance in the water and wastewater segment Schneider Electric South Africa
Maintenance, Test & Measurement, Calibration
In a time of water shedding, climate change and ageing infrastructure, the importance of maintenance and support in the water and wastewater segment cannot be overstated.
Read more...Quality test tools save costs at pulp and paper mill Comtest
Editor's Choice Maintenance, Test & Measurement, Calibration
A case study on how preventive maintenance and a few good test tools avoided unnecessary motor replacements at a pulp and paper company.
Read more...The logical solution to oil and gas industry corrosion
Maintenance, Test & Measurement, Calibration
The consequences of corrosion in the oil and gas industry can be astronomical. The simple culprit is metal reacting with oxygen and moisture, degrading it back to its natural state.
Read more...Lube tip: foaming is affected by oil level Wearcheck
Maintenance, Test & Measurement, Calibration
In a circulating system, it is crucial to check the oil level before introducing anti-foam agents to address a foaming problem.
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