What type of standard is a Zener diode reference system with a backup battery considered to be?

What type of standard is a Zener diode reference system with a backup battery considered to be?

• A. A primary standard
• B. A transfer standard
• C. A secondary standard
• D. A reference standard

Answer: (B)

A Zener diode reference system with a backup battery is best classified as a transfer standard. The primary role of a transfer standard is to serve as an intermediary tool used to compare and transfer measurements from one level of accuracy to another, between a primary standard (which is typically more accurate and stable) and secondary standards or calibrated instruments. Zener diodes are known for their ability to provide a stable reference voltage over varying temperature and current conditions, making them valuable in calibration applications. The addition of a backup battery ensures that the system maintains operational stability and accuracy even in the event of power loss, which further supports its role as a reliable transfer standard. In contrast, a primary standard would refer to a calibration standard of the highest accuracy that is recognized by National Metrology Institutes (NMIs) and usually is a physical quantity defined by a universal constant. A secondary standard is typically calibrated against a primary standard, but it does not achieve the same level of accuracy as a primary standard. A reference standard generally pertains to a standard against which others can be compared in a laboratory setting, but it is not specifically aligned with the characteristics that define a transfer standard.

A Zener diode reference system with a backup battery is best classified as a transfer standard. The primary role of a transfer standard is to serve as an intermediary tool used to compare and transfer measurements from one level of accuracy to another, between a primary standard (which is typically more accurate and stable) and secondary standards or calibrated instruments.

Zener diodes are known for their ability to provide a stable reference voltage over varying temperature and current conditions, making them valuable in calibration applications. The addition of a backup battery ensures that the system maintains operational stability and accuracy even in the event of power loss, which further supports its role as a reliable transfer standard.

In contrast, a primary standard would refer to a calibration standard of the highest accuracy that is recognized by National Metrology Institutes (NMIs) and usually is a physical quantity defined by a universal constant. A secondary standard is typically calibrated against a primary standard, but it does not achieve the same level of accuracy as a primary standard. A reference standard generally pertains to a standard against which others can be compared in a laboratory setting, but it is not specifically aligned with the characteristics that define a transfer standard.