Instruction Manual

Clarity II T56

PN-51-T56

May 2012

 

 

7.2.1Slope Calibration – Turbidity

This section describes how to conduct a 2-point calibration of the turbidity sensor against a user-prepared 20NTU standard. The calibration requires two steps. First, immerse the sensor in filtered water having very low turbidity and measure the sensor output. Next, increase the turbidity of the filtered water by a known amount, typically 20 NTU, and measure the sensor output again. The analyzer takes the two measurements, applies a linearization correction (if necessary), and calculates the sensitivity. Sensitivity is the sensor output (in mV) divided by turbidity. A typical new sensor has a sensitivity of about 10 mV/NTU. As the sensor ages, the sensitivity decreases. The figure below illustrates how turbidity calibration works. Before beginning the calibration, the analyzer does a dark current measurement. Dark current is the signal generated by the detector when no light is falling on it. The analyzer subtracts the dark current from the raw scattered light signal and converts the result to turbidity. In highly filtered samples, which scatter little light, the dark current can be a substantial amount of the signal generated by the detector.

7.2.2Standardize Calibration – Turbidity

The turbidity sensor can also be calibrated against a commercial standard. Stable 20.0 NTU standards are available from a number of sources. Calibration using a commercial standard is simple. Filtered deionized water is not required. Before beginning the calibration, the analyzer does a dark current measurement. Dark current is the signal generated by the detector even when no light is falling on it. The analyzer subtracts the dark current from the raw scattered light signal and converts the result to turbidity. In highly filtered samples, which scatter little light, the dark current can be a substantial amount of the signal generated by the sensor.

7.2.3Grab Calibration – Turbidity

If desired, the turbidity sensor can be calibrated against the turbidity reading from another instrument. The analyzer treats the value entered by the user as though it were the true turbidity of the sample. Therefore, grab sample calibration changes the sensitivity, it does not apply an offset to the reading.

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Calibration

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Emerson PN-51-T56 Slope Calibration Turbidity, Standardize Calibration Turbidity, Grab Calibration Turbidity
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PN-51-T56 specifications

The Emerson PN-51-T56 is a sophisticated and versatile process control valve designed to meet the demands of various industrial applications. This model is known for its robust performance, reliability, and advanced features that enhance its functionality and efficiency in process control.

One of the main features of the PN-51-T56 is its globe valve design, which allows for excellent flow regulation and precise control over fluid dynamics. The valve’s construction is designed to minimize pressure drop while ensuring high flow capacity, making it ideal for both liquid and gas applications in industries such as oil and gas, chemical processing, and water treatment.

The PN-51-T56 incorporates Emerson's latest technologies, including digital valve control systems. These systems enable seamless integration with existing control networks, allowing for real-time performance monitoring and diagnostics. With smart technologies, operators can optimize valve performance, reduce downtime, and improve overall process efficiency.

In terms of characteristics, the PN-51-T56 features a wide range of sizing options, providing versatility in various applications. It is available in different materials, allowing users to select the most appropriate material for their specific media and environmental conditions. The valve is built to withstand extreme temperatures and pressures, ensuring durability and longevity even in the most demanding situations.

Additionally, the valve's design considers maintenance ease, featuring accessible components that simplify repairs and periodic maintenance. This design philosophy minimizes operational interruptions and contributes to lower lifecycle costs.

Another key characteristic of the PN-51-T56 is its compliance with international standards and regulations, ensuring that users can rely on its safety and performance in critical applications.

In summary, the Emerson PN-51-T56 combines innovative technology with a robust design to deliver precise control in process applications. Its superior performance, durability, and ease of integration make it a preferred choice for industries requiring reliable process control solutions. With ongoing advancements in automation and digitalization, the PN-51-T56 positions itself as an essential tool for optimizing process efficiency and effectiveness in modern industrial settings.
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