IEEE 86-1987

IEEE 86-1987 is a recommended practice that defines basic per-unit quantities for AC rotating machines, helping engineers use a consistent basis for calculations and comparisons. It addresses the measurement and normalization of electrical quantities in power, energy, and industrial applications, where rotating machines must be evaluated with clarity and consistency. By standardizing per-unit definitions, IEEE 86-1987 supports more reliable analysis, design communication, and technical documentation across related equipment and systems.

About IEEE 86-1987

This standard focuses on the basic per-unit system as applied to AC rotating machines. In practical engineering work, per-unit values are often used to simplify machine ratings, operating characteristics, and comparative studies by expressing quantities relative to chosen bases. IEEE 86-1987 helps establish a common technical language for those calculations, reducing ambiguity when working with generators, motors, and associated power-system equipment. The document is especially useful where consistent interpretation of quantities is needed for design, testing, and specification work.

Where is IEEE 86-1987 used?

IEEE 86-1987 is commonly used in the analysis and documentation of AC rotating machines in power generation, industrial drives, and equipment selection workflows. It is relevant when engineers compare machine performance, calculate normalized values, or review test results using a per-unit basis. The standard may also support procurement and specification activities for rotating electrical equipment, where clear definitions help align expectations between design teams, manufacturers, and system operators.

Importance in practice

In practice, IEEE 86-1987 matters because per-unit definitions can affect how machine data is interpreted throughout engineering and testing. Consistent quantities improve design control, reduce calculation errors, and make it easier to compare equipment from different sources on a common basis. For rotating machines used in power and industrial systems, this helps support safer specifications, clearer performance evaluation, and more dependable technical communication during planning, review, and compliance-related work.

• Per-unit quantities for AC rotating machines
• Consistent calculation basis
• Design, testing, and specification support
• Applicable to motors and generators
• Useful for power and industrial applications