API St 670-2014 (2022) PDF

Full title and description

St API St 670-2014 (2022) — API Standard 670: Machinery Protection Systems. This standard specifies requirements for the design, installation, testing, operation and maintenance of machinery protection systems (MPS) used to protect rotating equipment and related systems from damaging operating conditions. It covers sensors, signal processing, alarms, trips, interfaces and verification procedures intended to reduce the risk of machinery failure and unplanned shutdowns.

Abstract

API Standard 670 defines minimum functional and performance requirements for machinery protection systems applied to industrial rotating equipment such as pumps, compressors, turbines and motors. The standard provides guidance on sensor types and locations, signal conditioning, alarm and trip logic, redundancy, response times, environmental and electrical requirements, documentation and testing. The 2014 edition (adopted/reissued in 2022 in this listing) reflects modern digital instrumentation, recommended practices for reliability and practices to ensure safe, repeatable protection of critical rotating machinery.

General information

• Status: Active / Adopted listing (2014 edition, noted 2022)
• Publication date: 2014 (4th edition) — referenced/adopted in 2022
• Publisher: American Petroleum Institute (API)
• ICS / categories: Machinery and rotating equipment; instrumentation and control; industrial safety (typical ICS groupings for machinery protection and vibration monitoring)
• Edition / version: Edition 4 (2014), with this record shown as 2014 (2022) adoption/notice
• Number of pages: Approximately 80–100 pages (typical edition length)

Scope

The standard applies to machinery protection systems intended to detect abnormal conditions and initiate alarms or protective actions to prevent equipment damage or unsafe operating conditions. It covers protection of rotating machinery through measurement and processing of vibration, position, speed and other relevant parameters. Included are requirements for sensor selection and placement, signal conditioning, processing units, alarm and trip setpoints, system architecture (including redundancy), electrical and environmental considerations, verification, commissioning and routine testing. It does not replace application-specific regulations but provides industry best-practice minimums for MPS design and operation.

Key topics and requirements

• Definitions and classification of machinery protection functions (alarm vs trip functions, severity levels).
• Sensor types, characteristics and mounting: proximity probes (eddy-current), velocity pickups, accelerometers, axial position probes, speed sensors.
• Recommended sensor placement and number of measurement points for common machinery types.
• Signal conditioning, filtering, and data acquisition requirements to ensure reliable detection of fault signatures.
• Processing units and logic: alarm/trip setpoint determination, voting logic, trip validation and fault masking rules.
• Reliability and redundancy principles for safety-critical protection paths, including diagnostics and fail-safe behavior.
• Electrical and environmental requirements: transient protection, grounding, shielding, temperature and ingress protection.
• Human-machine interface considerations: alarms, annunciation, recording and operator response guidance.
• Commissioning, factory acceptance testing (FAT), site acceptance testing (SAT) and periodic maintenance/calibration procedures.
• Documentation, specification, and traceability requirements for sensors, transmitters, processors and system configurations.

Typical use and users

Engineers and technicians in oil & gas, petrochemical, power generation, and heavy industry use this standard to specify, design, procure and operate machinery protection systems for rotating equipment (turbines, compressors, pumps, motors). Typical users include rotating equipment specialists, instrumentation and controls engineers, maintenance planners, reliability engineers, OEMs of rotating machinery and system integrators responsible for machinery protection and plant safety.

Related standards

Standards commonly referenced with API Std 670 include: ISO/IEC standards on vibration measurement and analysis, IEC 61508 / IEC 61511 on functional safety where protection is safety-related, IEC standards for electrical and environmental requirements, API standards for rotating equipment support and seals (for example API 614, API 682), and industry vibration standards such as ISO 20816. Plant-specific and sector-specific regulations and instrument manufacturer application guides are also typically consulted.

Keywords

API 670, machinery protection system, MPS, vibration monitoring, proximity probe, axial position, speed sensor, alarm, trip, redundancy, signal conditioning, commissioning, rotating equipment protection, instrumentation, reliability.

FAQ

Q: What is this standard?

A: This is API Standard 670, titled Machinery Protection Systems. It establishes minimum requirements for sensors, signal processing, alarms and trips to protect rotating machinery from damaging conditions.

Q: What does it cover?

A: It covers sensor selection and placement, signal conditioning, processing and logic for alarms and trips, system architecture and redundancy, environmental and electrical requirements, testing, commissioning and maintenance of machinery protection systems.

Q: Who typically uses it?

A: Rotating equipment engineers, instrumentation and controls engineers, reliability and maintenance personnel, OEMs and system integrators in industries with critical rotating machinery (refining, petrochemical, power generation, gas processing).

Q: Is it current or superseded?

A: The core listed edition is the 2014 publication. The entry here notes a 2022 listing/adoption. Users should verify with the issuing body (API) for any newer revisions or amendments beyond 2014 before applying the standard.

Q: Is it part of a series?

A: API 670 is part of API's suite of standards addressing rotating equipment, machinery reliability and plant operations; it is often used alongside related API standards covering associated equipment and systems.

Q: What are the key keywords?

A: Machinery protection, vibration monitoring, proximity probes, axial position, speed sensors, alarm/trip logic, redundancy, commissioning, rotating equipment protection.