What is BS EN 61515- Mineral insulated metal-sheathed thermocouple cables and thermocouples about?
BS EN 61515 is a safety standard on mineral insulated metal-sheathed thermocouple cables and thermocouples.
BS EN 61515 establishes the requirements for simplex, duplex, and triplex mineral-insulated metal-sheathed thermocouple cables and thermocouples, which are intended for use in general industrial applications. The abbreviation MIMS (for “mineral-insulated metal-sheathed”) will be used hereafter.
BS EN 61515 covers thermocouple cables and thermocouples with only base-metal conductors of Types T, J, E, K, and N. The specifications in BS EN 61515 apply to new thermocouple cables and thermocouple units as delivered to the user.
Note 1: External seals, terminations, connections, and other accessories are not within the scope of BS EN 61515.
Note 2: BS EN 61515 does not apply to precious metal thermocouple cables and thermocouples. The unique requirements for nuclear primary loop applications are dealt with in the other standards.
Who is BS EN 61515- Mineral insulated metal-sheathed thermocouple cables and thermocouples for?
BS EN 61515 on mineral-insulated metal-sheathed thermocouple cables and thermocouples is relevant to:
- Manufacturers of mineral insulated metal-sheathed thermocouple cables and thermocouples
- Testing authorities
- Electrical engineers
- Electricians
Why should you use BS EN 61515- Mineral insulated metal-sheathed thermocouple cables and thermocouples?
Mineral-insulated metal-sheathed thermocouple cable is a bendable cable consisting of one or more pairs of thermocouple conductors encapsulated in a metal protecting sheath, insulated from each other and from the sheath by a compacted mineral material.
BS EN 61515 reflects recent developments in production technology, sheath materials, and insulation materials. BS EN 61515 aims to be a flexible standard allowing suppliers to provide fit-for-purpose products at an acceptable cost. BS EN 61515 includes informative guidance to help users choose the products that meet their needs. BS EN 61515 gives alternative adjacent conductor configurations for duplex and triplex MIMS thermocouple cables and thermocouples. BS EN 61515 also gives recommendations to suppliers with respect to insulation composition. BS EN 61515 gives guidelines to users about temperature limits of operation. BS EN 61515 assists with tests that are divided into three categories, type tests, routine tests, and optional tests. The type tests and the routine tests are mandatory. Optional tests are not required unless they are requested. Details of the optional tests shall be determined by agreement between the supplier and the user.
Overall, BS EN 61515 is useful as it provides guidance on the mineral insulated metal-sheathed thermocouple cables and thermocouples which can be helpful for your business.
What’s changed since the last update?
BS EN 61515:2016 supersedes BS EN 61515:1996 which is withdrawn.
BS EN 61515:2016 replaces the first edition published in 1995. BS EN 61515:2016 constitutes a technical revision.
BS EN 61515:2016 includes the following significant technical changes with respect to the previous edition:
- Duplex and triplex are standardized
- Specification of insulation resistance is revised so that the user can choose the best product to fit the purpose
- “Table 2 Recommended maximum operating temperatures” in the previous version is
- expanded significantly including newly developed sheath material and it is moved to Annex C
- Test items and their methods are expanded, and a guide table (Table 4) is added for user-friendliness

