BS ISO 10924-1:2016 pdf download

BS ISO 10924-1:2016 pdf download.Road vehicles — Circuit breakers — Part 1: Definitions and general test requirements
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 (RT) (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. If 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 of ISO 10924. For appropriate cable sizes, see the applicable part of 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 of 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 be stabilized when three successive records, taken in intervals of 10 % of the previously elapsed duration of the test, but not less than 10 min intervals, advise no change. The test voltage shall not exceed the supply voltage maximum of the circuit breaker. NOTE Electrically reset circuit breakers (Type II) have a holding current after activation.
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, U Smax . 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 5.5.2.