BS/EN 50291-1-2018 pdf download.Gas detectors – Electrical apparatus for the detection of carbon monoxide in domestic premises Part 1: Test methods and performance requirements.
6.3.16.2 Method of test
At least two samples shall be tested. Units intended additionally for multiple-station interconnection shall be tested in that configuration with the maximum line resistance and maximum number of networked alarms, and the sound output measured on the carbon monoxide alarm subject to an abnormal CO condition or equivalent. Mains powered CO alarms shall be tested when connected to a source of rated voltage and frequency. Battery powered (or equivalent) CO alarms shall be tested with the battery depleted to a point just above or at the battery fault warning level. Mains powered CO alarms incorporating a stand-by power source shall be tested both as mains and battery powered as described above.
NOTE If more than five CO alarms can be interconnected it is permissible to interconnect a minimum of five alarms and simulate the remainder by an equivalent electrical load
The CO alarm shall be mounted on a mounting board as described in EN 54-3. The sound level shall be measured 3 m from the CO alarm either directly in front of the CO alarm or at an angle specified by the manufacturer within 450 of this.
A sound level meter conforming to EN 61672-1:2013. class 2 or better shall be used.
The A-weighted sound level shall be measured and recorded in dB using the F (Fast) detector indicator characteristic. In the case of fluctuating sound, the maximum value indicated during at least a complete cycle of the sound pattern shall be taken.
The measurement shall be made in a free field condition to minimize the effects of reflected sound energy. The ambient noise level shall be at least 10 dB (A) below the measured level produced by the alarm.
Free field conditions may be simulated by mounting the unit on a wooden board with the centre of the alarm under test at least 1.2 m above the ground (see EN 54-3) and with the microphone located 3 m from the unit and directly in front and conducting the test outdoors on a clear day with a wind velocity of not more than 8 km h-i and an ambient temperature of 15 °C to 25 °C.
Alternatively an anechoic chamber of not less than 28 m3, with no dimension less than 2 m and with an absorption factor of 0,99 or greater from 100 Hz to 10 kHz for all surlaces, may be used for this measurement.
6.3.16.3 Performance requirements
For battery operated alarms, the sound output shall be at least 85 dB(A) at 3 m after I mm of alarm operation and at least 82 dB(A) after 4 mm of alarm operation.
For mains powered alarms, the sound output shall be at least 85 dB(A) at 3 m after 4 mm of alarm operation.
For both battery operated and main powered alarms, the maximum sound output shall not be higher than 110 dB(A) at 3 m after 1 mm of alarm operation.
The maximum nominal frequency shall not exceed 3,5 kHz.
6.3.17 Battery fault warning
voltage Ue at intervals of at least 1 mm, until the fault warning is given. Record the supply voltage at which the warning is given as UE. At the voltage one step below the voltage at which the fault warning is given, expose the apparatus to test gas C In Table 4.
The voltage may be reduced in greater increments, when above 5 % of the fault warning voltage, if declared by the apparatus manufacturer.
Connect the apparatus to a stabilized power supply with a series variable resistor. Set the power supply to the rated battery voltage UR. Increase the resistance of the series resistor from zero in increments of no more than 1 ohm for apparatus powered with more than 5 V and increments of 0,1 ohm for apparatus powered with 5 V or less, at intervals of at least 1 minute until the fault warning is given Record the resistance of the series resistor at which the fault warning is given as RA. With voltage UR and resistance RA in series expose the apparatus to test gas C in Table 4.
The resistance may be increased in greater increments, when above 5 % of the fault warning resistance, if declared by the apparatus manufacturer.
6.3.17.2 Performance requirements
When exposed to test gas C in Table 4, the alarm shall operate according to the conditions in Table 5 for the power supply conditions in 6.3.17.1, Recovery from the alarm state shall take place within 6 mm when exposed to clean air. The unit shall give a low battery warning as per 5.4.6.
6.3.18 Battery capacity
6.3.18.1 Assessment
Guidance on the calculation of the expected battery service life is given in Annex B.
In the case of third party testing, the manufacturer shall supply details of the capacity of the recommended battery or batteries together with characteristic curves for voltage variation with time at (20 ± 20) °C for appropriate values of current drainage.
The current drawn, over the period of 1 hr, by the apparatus in the quiescent and routine testing conditions shall be measured.
This information may be used to check by calculation that the requirements in 6.3.18.2 can be met.
6.3.18.2 Performance requirements
The assessment of 6.3.18.1 shall indicate that the battery or batteries are capable of operating the apparatus
for the periods specified in 5.12.2.
The sound level specified in 6.3.16.2 is only required to be met at the start of the low battery voltage warning.
6.3.19 Battery reversal.BS/EN 50291-1-2018 pdf download.