BS ISO 8820-11-2020 pdf free download.Road vehicles — Fuse-links Part 11: Fuse-links with tabs (blade type) Type M (medium-high current)
This document specifies fuse-links with tabs (blade-type) Type M (medium-high current) for use in road vehicles. It establishes, for this fuse-link type, the rated current, test procedures, performance requirements and dimensions.
This document is applicable for fuse-links with a rated voltage of 32 V and a current rating of ≤80 A and a breaking capacity of 1 000 A intended for use in road vehicles.
This document is intended to be used in conjunction with ISO 8820-1 and ISO 8820-2. The numbering of the clauses corresponds to that of ISO 8820-1 whose requirements are applicable, except where modified by requirements particular to this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 2768-1, General tolerances — Part 1: Tolerances for linear and angular dimensions without individual tolerance indications
ISO 6722-1, Road vehicles — 60 V and 600 V single-core cables — Part 1: Dimensions, test methods and requirements for copper conductor cables
ISO 8820-1, Road vehicles — Fuse-links — Part 1: Definitions and general test requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8820-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Marking, labelling and colour coding
See ISO 8820-1 and Table 1.
5 Tests and requirements
5.1 General
5.1.1 Test criteria
In addition to carrying out the test procedures in accordance with ISO 8820-1 the following criteria shall apply.
Tests shall be performed following the test sequences in Table 2.
The test fixtures for electrical tests shall be designed in accordance with Figure 1.
The connection resistance shall be ≤0,35 mΩ for Type M (medium-high current) to ensure the proper function of the test fixture.
Fuse-links according to this document shall provide for visible evidence of an open fuse-element.
5.1.2 Test sequence
5.1.3 Test cable sizes
Test cable sizes shall be as given in Table 3. All tests for a particular fuse-link rating shall be performed using the same cable size.
Test cable sizes are specified to allow comparative fuse-link tests to be carried out. The cable size specified herein does not necessarily indicate the size of the cable to be used in the vehicle application.
5.2 Voltage drop
5.2.1 Tests
The voltage drop U AB shall be measured at points A and B across the fuse-link tabs as shown in Figure 1.
Where not specified in the Figure 2, the common tolerances shall be in accordance with tolerance class m as specified in ISO 2768-1.
5.3 Transient current cycling
5.3.1 Test
See Figure 3 and ISO 8820-1. At an elapsed time of 0,025 s on-time, the current shall fall to a value between 1,65 I R and 2,5 I R . At no time during the first 4,5 s of each cycle the steady state current shall fall below 0,9 I R
5.3.2 Requirement
See ISO 8820-1.
5.4 Environmental conditions
See ISO 8820-1.
5.5 Operating time rating
5.5.1 Test
See ISO 8820-1. For I R the test duration is 100 h.
5.5.2 Requirement
See Table 5.
After activation, the current through the fuse-link shall not exceed 0,5 mA at the rated voltage of the fuse-link.BS ISO 8820-11 pdf download