Document ID: chunk:federal_register_of_legislation:F2018L01513:body:0:p9
Version: federal_register_of_legislation:F2018L01513
Segment Type: other
Provision Reference: 
Character Range: 26712–29615

audible warning device, audible warning system, multiple audible warning system. The microphone must be positioned facing the front surface emitting sound of the audible warning device, audible warning system, multiple audible warning system in the direction in which the maximum sound level can be measured. (see figures in Annex 4).

 In the case of audible warning device with several outlets, the distance shall be determined in relation to the plane of the nearest outlet to the microphone.

6.3.3. The audible warning device, audible warning system, multiple audible warning system shall be mounted rigidly, by means of the equipment indicated by the manufacturer, on a support whose mass is at least ten times that of the audible warning device, audible warning system, multiple audible warning system under test and not less than 30 kg. In addition, arrangements must be made ensuring that reflections on the sides of the support and its own vibrations have no appreciable effect on the measuring results.

6.3.4. The audible warning device, audible warning system, multiple audible warning system shall be supplied with current, as appropriate, at the following voltages:

6.3.4.1. In the case of audible warning device, audible warning system, multiple audible warning system supplied with direct current, at a voltage measured at the terminal of the electric power source of 13/12 of the rated voltage;

6.3.4.2.  In the case of audible warning device, audible warning system, multiple audible warning system supplied with alternating current, the current shall be supplied by an electric generator of the type normally used with this type of audible warning device, audible warning system, multiple audible warning system. The acoustic characteristics of the audible warning device, audible warning system, multiple audible warning system shall be recorded for electric generator speeds corresponding to 50 per cent, 75 per cent and 100 per cent of the maximum speed indicated by the manufacturer of the generator for continuous operation. During this test, no other electrical load shall be imposed on the electric generator. The endurance test described in paragraph 6.4. shall be carried out at a speed indicated by the manufacturer of the equipment and selected from the above range.

6.3.5. If a rectified current source is used for the test of an audible warning device, audible warning system, multiple audible warning system supplied with direct current, the alternating component of the voltage measured at its terminals, when the warning devices are in operation, shall not be more than 0.1 V, peak to peak.

6.3.6. For audible warning device, audible warning system, multiple audible warning system supplied with direct current, the resistance of the connecting leads, expressed in ohms, including terminals and contacts, shall be as close as possible to (0,10/12) x rated voltage