BS EN 61243-3-2014 pdf download.Live working – Voltage detectors Part 3 : Two-pole low-voltage type.
5.3.1.5 Successive Indication
The test for successive indication can be combined with the test for threshold voltage values by verifying additionally that the level Indication fulfill the requirements of 4.2.1.4 when decreasing the test voltage.
5.3.2 Clear perceptibility of visual indication
5.3.2.1 Type test
The test shall be performed at the ELV limit and at a test voltage of 0.85 times the nominal voltage or 0.85 times the particular step within the nominal voltage range and at 0,85 times the lower nominal voltage of the nominal voltage range under a.c. or d.c. voltage. For an a.c./d.c. voltage detector, the test shall be performed for each type of voltage. The permissible tolerance of the test voltage shall be
For a voltage detector having an internal energy source, it shall be discharged until the non- readiness indication appears as mentioned in the instructions for use. The test duration may be reduced by supplying the voltage detector with an external power source with a sufficient energy level.
The voltage detector shall be placed in a room with low light reflection and so clamped that it can be turned around a horizontal axis at the display of the indicator and can be rotated around its longitudinal axis. At a distance of 150 mm behind the horizontal turning axis, a matt grey surface with identification colour IEC 60304 grey’ (for example, a painted wall or paper screen) with a diameter of at least 500 mm shall be arranged vertically in the room in such a way that its centre is behind the indicator of the voltage detector.
The voltage detector and the mat grey surface shall be lit by a diffuse white light from two halogen light sources, placed at least 1 m from the voltage detector, in accordance with Figure 6. The arrangement shall be such that the light reflected from the matt grey surface to the indicator of the voltage detector has an illumination of 3 500 lx. For voltage detectors with a nominal voltage or nominal voltage range starting below the ELV limit indication, the illumination shall also be 3 500 lx for the indicating range c50 V.
At a distance of 750 mm from the voltage detector, the forehead stop for the observer shall be arranged. as shown by item 5 in Figure 6.
The voltage detector shall be rotated from the original vertical position to an angle of 15° and back to the original position, the display of the indicator being turned by rotation around the longitudinal axis of the detector by an angle of 10° to the right and to the left In order to identify the most unfavourable position of the indication.
5.3.3 Clear perceptibility of audible indication (when available)
5.3.3.1 Type test
The test shall be performed at the ELV limit and at a test voltage of 0.85 times the nominal voltage or 0,85 times the particular step within the nominal voltage range and at 0,85 times the lower nominal voltage of the nominal voltage range under ac. or d.c. voltage. For an a,c./d.c. voltage detector, the test shall be performed for each type of voltage. The permissible tolerance of the test voltage shall be _%.
For a voltage detector having an internal energy source, it shall be discharged until the non- readiness indication appears as mentioned in the instructions for use. The test duration may be reduced by supplying the voltage detector with an external power source with a sufficient energy level.
Sound pressure levels shall be measured according to the specifications of ISO 3744, in terms of the main requirements (grade 2 accuracy, measurement surface, microphone positions, background noise, etc.), except for the fact that the measurements are carried out in a free-field, without the reflecting plane referred to in ISO 3744.
The absorption coefficient of the environment shall be at least 0,9 Hz at 700 Hz (see ISO 354). The measurement may be carried out in an anechoic room duly compliant with ISO 3745; in this case, the required absorption conditions are naturally fulfilled. In a semianechoic room or any other free-field over a reflecting plane environment in accordance to ISO 3744, the absorption of the reflecting plane can generally be obtained by covering this surface with a sound absorbing material approximately 20 cm thick and with a minimum surface area of 2,0 m x 2,0 m.
In addition, the background noise level of the room shall be at least 6 dB, and preferably more than 15 dB. below the noise of the voltage detector under test, within the frequency range of interest.
The instrumentation system, including the microphone and related cables, shall meet the requirements for a type 1 instrument as specified in IEC 61672-1 for sound level meters (required for continuous signal) or, for integrating-averaging sound level meters (required for intermittent sounds). The filters used shall meet the requirements for a class 1 instrument specified in IEC 61260.
During each series of measurements, a sound calibrator with an accuracy of class 1 specified in IEC 60942 shall be applied to the microphone to verify the calibration of the entire instrument system.BS EN 61243-3-2014 pdf download.