BS ISO 10924-1:2016 download free.Road vehicles Circuit breakers Part 1 : Definitions and general test requirements.
1 Scope
This part of ISO 10924 defines terms and specifies general test requirements for circuit breakers for use in road vehicles with a nominal voltage of 12 V d.c., 24 V d.c. 48 V d.c. and 450 V d.c.
This part of ISO 10924 Is Intended to be used In conjunction with other parts of ISO 10924 The numbering of Its clauses corresponds to thai of this part of ISO 10924 whose requirements are applicable, except where modified by requirements particular to this part of ISO 10924.
This part of ISO 10924 is not applicable to circuit breaker holders (electrical centres or fuse-holders) used in vehicLes.
2 Normative references
The following documents, In whole or in part, are normatIvely referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (Including any amendments) applies.
ISO 6722-1, Road vehicles — 60 V and 600 V single-core cables — Port 1: DImensions, test methods and requirements for copper conductor cables
ISO 8820—1. Road vehicles — Fuse-links — Part 1: Deflnioons and general test requirements
ISO 8820-3, Road vehides — Fuse-links — Part 3: Fuse-links with tabs (blade type) 7>pe C (medium), pe E (high current) and 7).’pe F (miniature)
ISO 16750-1, Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Part 1: General
ISO 16750-3, Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Part 3: Mechanical loads
ISO 16750-4, Road vehicles — Environmental conditions and testing for electrical and electronic equipment — Port 4: ClImatic loads
ISO 16750-5, Road vehicles — Environmental conditions and testing [or electrical and electronic equipment — PartS: Chemical loads
IEC 60068-2-70, Environmental resting — Parr 2: Tests — Test Xb: Abrasion of markings and letterings caused by rubbing offingers and hands
3 Terms and definitions
For the purposes of BS ISO 10924-1, the terms and definitions given in ISO 16750-1, ISO 8820-1 and the following apply.
3.20
voltage drop
LID
voltage measured between specified measuring points at a specilled current
(SOURCE: ISO 8820-1:2014. 3.14j
4 Marking, labelling and colour coding
The circuit breakers shall be permanently marked with the following to be externally visible:
rated current (IR) In Ampere (A), the value oIthe rated current (lit) without unit Is accepted;
— supply voltage maximum (Usni.ax) In (V);
— colour coding:
— manufacturer’s name, trademark and/or symbol;
— part no, or Identification.
5 Tests and requirements
5.1 General
5.1.1 General test conditions
If not otherwise specified, all tests shall be performed at room temperature (ItT) (23 ± 5) °C at a relative humidity (RH) of 45 % to 75% (standard condition).
At the beginning of the electrical tests, a direct current shall be fixed at the rated value. This current shall be measured with an appropriate method. II not otherwise specified, no further adjustments during the tests are allowed.
All electrical measurement equipment shall have a tolerance of less than ±2%. Mount the circuit breaker in a test fixture (holder) as specified in the applicable part or iSO 10924.
For appropriate cable sizes, see the applicable part ol Iso 10924. Temperature measurements shall be performed at no forced air flow.
Connections shall be made to the circuit breaker with copper cables according to ISO 6722.1. The cable length between the test fixture and the rest of the test set-up shall be (500 ± 50) mm, if not otherwise specified.
Measure the connection resistance using a dummy with dimensions as specified in the appropriate part of ISO 10924. Use a current as specified in the appropriate part or iso 10924 for this measurement. For the used voltages, see Table 1.
5.5.2 Test
The test fixture and circuit breaker shall be stabilized at RT before each test. The power supply shall be adjusted to the test current (multiple rated current) as specified in the applicable parts of ISO 10924. Then, the test currents shall be applied to the circuit breaker. A measurement is considered to b stabilized when three successive records, taken in intervals of 10% of the previously elapsed duration ci the test, but not less than 10 mm intervals, advise no change.
The test voltage shall not exceed the supply voltage maximum of the circuit breaker.
NOTE Electrtcally reset circuit breakers (Type II) have a holding current after activation.
5.5.3 RequIrement
The operating time of the circuit breaker shall be within the limits as shown in the applicable parts of
ISO 10924.
5.6 Current steps
5.6.1 Purpose
This test is to evaluate the circuit breaker’s ability to withstand the heating due to prolonged low level overloads.
5.6.2 Test
First, a current equivalent in value to the rating of the circuit breaker under test shall be applied for duration of S mm. Then, the current shall be sequentially increased in steps of 2,5 % of the circuit breaker rating inS mm intervals until the circuit breaker trips.
5.6.3 Requirement
After the current step test, the current through the circuit breaker shall not exceed the value specified in the appropriate part of ISO 10924 at the supply voltage maximum. Usnuz. The circuit breaker shall be removable from the test fixture by its intended method after returning to RT. The devices subjected to the current step test shall additionally be subjected to operating time rating test as described in 52.
5.7 No current trip and reset temperature
5.7.1 Purpose
This test Is to evaluate the circuit breake?s design variations and ambient temperature compensation.
5.72 Test
The circuit breaker shall be placed Into a climate chamber for 30 mm at a temperature as follows:
— lór rated current of 10 A and loss: 72± 2
— for rated current above 10 A: 102 ± 2 C.
Alter the 30 mm, the temperature shall be raised at a rate not exceeding I °C/mln and the temperature at which the circuit breaker opens shall be recorded. After the circuit breaker has opened, the temperature at a rate not exceeding 1 °C/min shaLl be decreased and the temperature at which the circuit breaker closes shall be recorded. If more than one circuit breaker is tested at one time, they shall all open before the temperature is decreased.
If a circuit breaker does not trip up to a maximum ambient temperature depending on the plastic material, but not less than 180 °C the test shall be terminated. In this case, the circuit breaker shall be
5.10.2 Test
Forces shall be applied to the terminals of the circuit breaker as specified In the appropriate part of
ISO 10924.
5.10.3 RequIrement
See ISO 8820-3.
5.11 Endurance
5.11.1 Purpose
This test is to evaluate the circuit breakers ability to withstand a normal cycling during its life.
5.11.2 Test
The test shall be performed at USrn.ix ‘
2
0 V with a (2,0 ± 0,5) ms time constant. Test sequences and
cycling profiles are shown In the applicable parts of ISO 10924. Perform this test at standard conditions and ambient temperature as specified in the appropriate part of ISO 10924.
— Type I circuit breakers
A multiple IR shall be applied to the circuit breaker for a length of time allowing it to cycle continuously as specified in the appropriate part of ISO 10924. See Figure A. 1 for the cycling profile.
— Type II circuit breakers
A multiple lit shall be applied to the circuit breaker for the numbers of cycles as specified in the appropriate part of ISO 10924. The test current shall be applied for 60 s each cycle. Multiple interruptions are possible with this type of CII and allowed during this time. The resetting time shall be long enough for the circuit breaker to reclose the circuit. At the last cycle, the circuit shall remain on at a voltage level of 0,94 IISmax for a period of 12 h. After 12 h. the circuit breaker shall be switched off no cool down to reclose the circuit. Alter that, the test shall be repeated as specified in the appropriate part of ISO 10924. See Figure A.2 for the cycling profile.
— Type Ill circuit breakers
A multiple it shall be applied to the circuit breaker for numbers of cycles as specified in the appropriate part of ISO 10924 utilizing the reset mechanism on the circuit breaker. See Figure Al for the cycling profile.
— Type IV circuit breakers
The circuit breaker shall be mechanically cycled utilizing the trip mechanism and subsequently, the reset mechanism for numbers of cycles as specified in the appropriate part of ISO 10924 while lit shall be applied to the circuit breaker. See Figure Al for the cycling profile.
5.11.3 Requirement
After the test, the current through the circuit breaker shall not exceed the value as specified In the appropriate part of ISO 10924 at the rated voltage. The following shall not occur:
— permanent arcrng;
— ruptures to the external surfaces shall not be visible to the naked eve.