Document ID: chunk:federal_register_of_legislation:F2018L01513:body:0:p10
Version: federal_register_of_legislation:F2018L01513
Segment Type: other
Provision Reference: 
Character Range: 29343–32195

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 in volt.

6.3.7. Under the conditions set forth above, the sound-pressure level weighted in accordance with curve A shall not exceed the following values:

(a)  115 dB(A) for audible warning device, audible warning system, multiple audible warning system intended principally for vehicles of categories L3 to L5 with a power less than or equal to 7 kW;

(b)  118 dB(A) for audible warning device, audible warning system, multiple audible warning system intended principally for vehicles of categories M, N and L3 to L5 with a power greater than 7 kW.

6.3.7.1. In addition, the sound-pressure level in the frequency band 1,800 to 3,550 Hz shall be greater than that of any component of a frequency above 3,550 Hz and in any event equal to or greater than:

(a) 95 dB(A) for audible warning device, audible warning system, multiple audible warning system intended principally for vehicles of categories L3 to L5 with a power less than or equal to 7 kW;

(b) 105 dB(A) for audible warning device, audible warning system, multiple audible warning system intended principally for vehicles of categories M, N and L3 to L5 with a power greater than 7 kW.

6.3.7.2. Audible warning device,  audible warning system, multiple audible warning system meeting the sound characteristics mentioned in (b) may be used on the vehicles mentioned in (a).

6.3.7.3.  In the case of multiple audible warning systems, the minimum values of sound pressure level as specified in paragraph 6.3.7.1. shall be obtained when each of the constituent units is operated separately. The maximum values of the sound pressure level as specified in paragraph 6.3.7. shall not be exceeded when all the constituent units are operated simultaneously.

6.3.8. The specifications indicated above shall also be met by an audible warning device, audible warning system, multiple audible warning system subjected to the endurance test referred to in paragraph 6.4. below, with the supply voltage varying between 115 per cent and 95 per cent of its rated voltage for audible warning device, audible warning system, multiple audible warning system supplied with direct current or, for audible warning device, audible warning system, multiple audible warning system supplied with alternating current, between 50 per cent and 100 per cent of the maximum speed of the generator indicated by the manufacturer for continuous operation.

6.3.9. The time lapse between the moment when the audible warning device, audible warning system, multiple audible warning system is actuated and the moment when the sound reaches the minimum