IEC 61557-9-2023 PDF

Full title and description

Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC — Equipment for testing, measuring or monitoring of protective measures — Part 9: Equipment for insulation fault location in IT systems. This publication (IEC 61557-9:2023, edition 4.0) specifies requirements for insulation fault location systems (IFLS) used to localize insulation faults in unearthed IT AC and DC systems, independent of the measuring principle.

Abstract

IEC 61557-9:2023 is a technical revision of the Part 9 series that defines functional, safety and performance requirements for equipment and systems intended to detect and locate insulation faults in IT (unearthed) low-voltage distribution networks. It covers systems for IT AC networks (and AC networks with galvanically connected DC circuits) up to 1 000 V AC and unearthed IT DC networks up to 1 500 V DC, and is intended to be used together with the common requirements in IEC 61557-1.

General information

• Status: Current / published (definitive edition).
• Publication date: 2023 (published December 2023, edition 4.0).
• Publisher: International Electrotechnical Commission (IEC).
• ICS / categories: 25.040.40 (Measuring and testing).
• Edition / version: Edition 4.0 (2023).
• Number of pages: 66 pages (publication PDF).

Scope

Specifies requirements for insulation fault location systems (IFLS) that localize insulation faults anywhere in unearthed IT AC systems and unearthed IT AC systems with galvanically connected DC circuits up to 1 000 V AC, and in unearthed IT DC systems up to 1 500 V DC. The scope is independent of the measuring principle used and is intended to be applied alongside the general requirements of IEC 61557-1; IT systems are defined in IEC 60364-4-41.

Key topics and requirements

• Functional requirements for insulation fault localization systems (detection, localisation, indication, and information provided to users).
• Performance criteria and measurement accuracy for fault location across IT AC and DC systems within the standard voltage limits.
• Safety and protection requirements for both the measuring equipment and connected systems (electrical safety, operator protection and interaction with the monitored installation).
• Requirements independent of measurement principle — applicability to a variety of locating techniques and system implementations.
• Information and documentation requirements, including installation, commissioning, operation, and testing instructions for IFLS devices.

Typical use and users

Used by manufacturers of insulation fault location equipment, electrical test and maintenance teams, design engineers for low-voltage IT distribution systems, third-party testing laboratories, and standards/approval bodies. Typical applications include hospitals, industrial installations, maritime and other facilities where continuous operation and early detection of insulation faults in unearthed systems are required.

Related standards

IEC 61557-9:2023 is part of the IEC 61557 series and is intended to be used with IEC 61557-1 (general requirements). It references IT system definitions and practices in IEC 60364-4-41. The 2023 edition cancels and replaces the 2014 edition (IEC 61557-9:2014).

Keywords

insulation fault location, IFLS, IT system, unearthed system, low-voltage, insulation monitoring, fault localisation, IEC 61557, electrical safety, test equipment

FAQ

Q: What is this standard?

A: IEC 61557-9:2023 is the fourth edition of Part 9 of the IEC 61557 series, providing requirements for equipment and systems that locate insulation faults in unearthed (IT) low-voltage electrical distribution systems.

Q: What does it cover?

A: It covers functional, performance and safety requirements for insulation fault location systems applicable to IT AC systems (and AC with galvanically connected DC) up to 1 000 V AC and IT DC systems up to 1 500 V DC, independent of the locating technique used. It also includes documentation, installation and testing information expected from suppliers.

Q: Who typically uses it?

A: Manufacturers of IFLS equipment, electrical engineers, facility maintenance and testing personnel (especially in critical-continuity environments such as healthcare and industry), and testing/inspection bodies use this standard to design, select, install and verify fault-location equipment.

Q: Is it current or superseded?

A: It is current: IEC 61557-9:2023 (edition 4.0) is the latest published edition and cancels and replaces IEC 61557-9:2014.

Q: Is it part of a series?

A: Yes — it is Part 9 of the IEC 61557 series, which contains multiple parts addressing requirements for testing, measuring and monitoring protective measures in low-voltage distribution systems; IEC 61557-1 provides the common/general requirements referenced by the part.

Q: What are the key keywords?

A: Key keywords include: insulation fault location, IFLS, IT systems, unearthed system, insulation monitoring, low-voltage testing, electrical safety, IEC 61557.