ISO 7240-18:2017

ISO 7240-18:2017 pdf free.Fire detection and alarm systems – Part 18: Input/ output devices.
4 Requirements
4.1 Compliance
4.1.1 In order to comply with this document, the input/output device shall:
a) meet the requirements of Clause 4. which shall be verified by visual inspection or engineering assessment,
b) be tested as specified in Clause 5, and shall meet the requirements of the tests, and
c) meet the requirements of Clauses 7 and a which shall be verified by visual inspection.
4.1.2 For input/output devices integrated into another device that is already covered by an existing part of ISO 7240, the environmental conditioning shall be performed in accordance with that part of ISO 7240, with the addition of the functional tests before, during and/or after conditioning, as required in this document. In some detector standards, the dry heat (operational) test is conducted in special test equipment (e.g. in the heat tunnel for heat detectors). The required functional testing of the integrated input/output device before, during and after the dry heat conditioning may be done with this equipment, if this is possible without disrupting the detector measurements. Otherwise, a separate dry heat test, with the same conditioning, shall be conducted. For heat detectors, the test temperature is the maximum application temperature.
4.2 Monitoring of detachable devices
If an input/output device is detachable (i.e. it is attached to a detachable mounting base), then a means shall be provided for a remote monitoring system (e.g. the FDCIE) to detect the removal of the device from the base, in order to give a fault signal.
4.3 Requirements for software controlled devices
4.3.1 General
For input/output devices that rely on software control in order to fulfil the requirements of this document, the requirements of 4.3.2 and 4.3.3 shall be met.
4.3.2 Software design
in order to ensure the reliability of the device, the following requirements for software design shall apply.
a) The software shall have a modular structure.
b) The design of the interfaces for manually and automatically generated data shall not permit invalid data to cause error in the program operation.
c) The software shall be designed to avoid the occurrence of deadlock of the program flow.
4.3.3 Storage of programs and data The program necessary to comply with this document and any preset data, such as manufacturer’s settings, shall be held in non-volatile memory. Writing to areas of memory containing this program and data shall be possible only by the use of some special tool or code and shall not be possible during normal operation of the device. Site-specific data shall be held in memory that can retain data for at least two weeks without external power to the device, unless provision is made for the automatic renewal of such data, following loss of power, within 1 h of power being restored.
5 Tests
5.1 General
5.1.1 Atmospheric conditions for tests Unless otherwise stated in a test procedure, carry out the testing after the test specimen has been allowed to stabilize in the standard atmospheric conditions for testing as specified in IEC 600 68-1 as follows:
— temperature: (15 to 35) °C;
— relative humidity: (25 to 75) %;
— air pressure: (86 to 106) kPa. The temperature and humidity shall be substantially constant for each environmental test where the standard atmospheric conditions are applied.
5.1.2 Mounting arrangements
The specimen shall be mounted by its normal means of attachment in accordance with the manufacturer’s instructions. If these instructions describe more than one method of mounting, then the method considered to be most unfavourable shall be chosen for each test.
5.1.3 Operating conditions for tests If a test method requires that a specimen be operational, then the specimen shall be connected to suitable supply and monitoring equipment with characteristics as required by the manufacturer’s data. Unless otherwise specified in the test method, the supply parameters applied to the specimen shall be set within the manufacturer’s specified range(s) and shall remain substantially constant throughout the tests. The value chosen for each parameter shall normally be the nominal value or the mean of the specified range. The details of the supply and monitoring equipment used shall be given in the test report (see Clause 6).
5.1.4 Tolerances Unless otherwise stated, the tolerances for the environmental test parameters shall be as given in the basic reference standards for the test, e.g. the relevant parts of IEC 60068-2. If a requirement or test procedure does not specify a tolerance or deviation limits, then deviation limits of ±5 % shall be applied.
5.1.5 Functional test
Each function of the input/output device shall be activated by a suitable means in accordance with the manufacturer’s specification and appropriate observations or measurements shall be made to confirm the correct operation of the device.
NOTE The variety and the diversity of the equipment within the scope of this document make it difficult to define the precise details of this functional test. This functional test is intended to exercise each function of the device in a simple way. A more complete assessment of the performance of these functions, in accordance with the manufacturer’s specification, is made in the performance and variation in supply voltage test (see .5.2).ISO 7240-18 pdf download.

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