White paper - How to calibrate a 10-50mA instrument

Product catalog summary

Introduction
The document discusses the calibration of 10–50 mA instruments, which are less common today compared to the standard 4–20 mA instruments. Beamex has introduced the MC6 calibrator to address the challenges of calibrating these instruments.

Historical Context
Before electronic controls, instrumentation was managed pneumatically. The transition to electronic controls in the 1950s introduced milliamp outputs, with 10–50 mA being one of the early standards. The 4–20 mA standard was later established due to its safety and efficiency, as it reduces the risk of electrical shock and provides a 'live zero' for better signal interpretation.

Standardization and Challenges
The International Society of Automation (ISA) released the ISA50 standard in 1972, which specified 4–20 mA as the standard but acknowledged 10–50 mA as an alternative. Despite the shift to 4–20 mA, some industries, like nuclear power, still use 10–50 mA instruments due to regulatory constraints.

Solution: Beamex MC6 Calibrator
The Beamex MC6 is a multifunctional process calibrator that can measure up to 100 mA and generate up to 55 mA, making it suitable for 10–50 mA instruments. It features a split-screen display for simultaneous generation and measurement, and includes a built-in communicator for smart instrumentation configuration. The MC6 also supports pressure calibration with internal modules, reducing the need for additional equipment.

Conclusion
The Beamex MC6, combined with Beamex CMX calibration software, offers a comprehensive solution for documenting calibration processes, supporting paperless and regulatory environments.

Catalog excerpts

White paper - How to calibrate a 10-50mA instrument-1

Calibration White Paper WORLD-CLASS CALIBRATION SOLUTIONS™

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White paper - How to calibrate a 10-50mA instrument-2

BEAMEX Calibration White Paper How to calibra te a 10–50 mA instrument Today, the market consists mostly of 4–20 mA output instruments, but several 10–50 mA instruments still exist. Finding a calibrator that will measure and source the 10–50 mA instruments is a challenge. Beamex has recently introduced a new tool, the Beamex MC6 calibrator and communicator, to help overcome these challenges. urrent loops: 4–20 mA, 10–50 mA, why not 5–25 mA? That is the question that many engineers asked when standardizing on a milliamp output for instrumentation. Believe it or not, several factors were considered...

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White paper - How to calibrate a 10-50mA instrument-3

BEAMEX Calibration White Paper a shock. In the beginning, 0–20 mA was likely considered, but engineers quickly realized the potential danger a 0 mA signal could infer. First, it could mean that the instrument is at the low side, 0%, of its range, but it could also mean that a line to the instrument got cut or removed. It was quickly determined that the low side of the milliamp signal needed to be above 0 mA to recognize a true low side of the instrument range. This is referred to as the “live zero” phenomenon. Four was decided upon because it provides the minimum amperage to power loop-powered...

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White paper - How to calibrate a 10-50mA instrument-4

BEAMEX Calibration White Paper The Beamex MC6 displays a split screen for calibration. The upper window displays the generated or simulated value, while the lower screen displays the measured value. many calibrators were designed to generate 50 mA. When ISA issued standard ISA50 in 1972, plants started replacing their 10-50 mA instruments with the newly standardized 4-20 mA instruments; however, some industries could not adapt to these changes. Forty-one years later, some of these 10-50 mA instruments are still being used, especially in industries such as nuclear power where licensing complicates...

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