Pressure Measurement | Methods | Part-1/3 | Electrical Instruments ( EIM ) | Lec - 82

TL;DR

This video covers methods to measure pressure using electrical signals and transducers.

Transcript

hi friends in this video I am going to discuss about the measurement of pressure so it is also another type of physical quantity in which we can measure using the electrical quantities like voltage and current so any type of physical quantity we have seen so far in the force displacement and proximity and various measurements all these are can be m... Read More

Key Insights

• 🈸 Understanding pressure measurement methods is vital for engineering and scientific applications, as pressure is a fundamental physical quantity.
• 🖐️ Pressure transducers play a significant role in converting mechanical pressure into electrical signals, enabling easier measurement and monitoring.
• 🛟 Accurate measurement techniques classify pressure into three major categories: absolute, gauge, and differential, each serving different operational needs.
• 🤒 The unit of pressure, Pascal, is derived from Newton per square meter, clarifying relationships between force and area.
• 🈸 Various pressure measurement devices customize for specific applications, such as piezoelectric, capacitive, and resistive transducers, each with unique functioning principles.
• 🈸 Knowledge of whether pressure readings are absolute or gauge impacts interpretation and application in various industries.
• ❓ The choice of pressure measurement method influences the reliability of pressure data, particularly in critical systems like altimeters and cardiovascular monitoring devices.

Questions & Answers

Q: What is a pressure transducer and how does it work?

A pressure transducer, often called a pressure transmitter, converts pressure into an analog electrical signal. This process revolves around creating a relationship between the applied pressure and an electrical output, employing changes in resistance, capacitance, or inductance to quantify pressure effectively.

Q: What are the different units used to express pressure?

Pressure can be expressed in several units, the most common being Pascal (Pa), which is Newtons per square meter. Other units include pounds per square inch (PSI), atmospheres (ATM), inches of mercury (inHg), and millimeters of mercury (mmHg). Familiarity with these units is essential for accurate pressure measurement across various applications.

Q: Can you explain the difference between absolute pressure and gauge pressure?

Absolute pressure measures pressure relative to a perfect vacuum (zero Pascals), considering atmospheric pressure. In contrast, gauge pressure measures pressure relative to ambient atmospheric pressure, excluding its effects. This distinction is crucial in applications like altimeters, which require absolute measurements, while tire pressures utilize gauge measurements.

Q: What is differential pressure measurement, and how is it used?

Differential pressure measurement involves comparing two pressure points within a system rather than referencing atmospheric pressure. This technique is useful for maintaining relative pressure between vessels, such as a compressor tank and its associated feed line. It provides an accurate assessment of pressure differences critical for system control.

Summary & Key Takeaways

• The video discusses various types of pressure transducers and how they convert pressure into electrical signals for measurement, emphasizing the importance of understanding these devices.

• Pressure is defined as force per unit area, with SI units being Pascal and alternatives like PSI. Measurement methods include gauge, absolute, and differential pressure measurements.

• Different types of pressure measurements are outlined, along with their applications, such as altimeters and tire pressure, highlighting how reference points affect the measurement type.