Document ID: chunk:federal_register_of_legislation:F2022C01070:body:0:p21
Version: federal_register_of_legislation:F2022C01070
Segment Type: other
Provision Reference: 
Character Range: 55814–58591

(2 ± 1) Hz
 On time = off time ± 10 %
18.2.3.2. Audible signal device with frequency modulation :
 acoustical, etc... data according to ECE Regulation No. 28, Part I but equal pas-sage of a significant frequency range within the above-mentioned range (1,800 through 3,550 Hz) in both directions.
 Passage frequency   (2 ± 1) Hz
18.2.3.3. Sound level
 The sound source shall be :
 either an audible warning device approved under ECE Regulation No. 28, Part I
 or a device meeting the requirements of ECE Regulation No. 28, Part I, paragraphs 6.1. and 6.2.  However, in the case of a different sound source from the original equipment audible warning device, the minimum sound level may be reduced to 100 dB(A), measured under the conditions of ECE Regulation No. 28, Part I.
18.3. Optical alarm - if fitted
18.3.1. General
 In the event of intrusion into or interference with the vehicle the device shall activate an optical signal as specified in paragraphs 18.3.2. and 18.3.3. below.
18.3.2. Duration of the optical signal
 The optical signal shall have a duration between 25 s and 5 min. after the alarm has been activated. The unsetting of the alarm system shall immediately stop the signal.
18.3.3. Type of optical signal
 Flashing of all direction indicators and/or passenger compartment light of the vehicle, including all lamps in the same electrical circuit.
 Trigger frequency   (2 ± 1 ) Hz
 In relation to the audible signal, also asynchronous signals are allowed.
 On time  =  off time  ±  10 %
18.4. Radio alarm (pager) - if fitted
 The AS may include a facility generating an alarm signal by radio transmission.
18.5. Alarm system setting lock
18.5.1. When the engine is in its running mode, deliberate or inadvertent setting of the alarm system shall be impossible.
18.6. Setting and unsetting of the AS
18.6.1. Setting
 Any suitable means of setting of the AS is allowed, provided that such means does not inadvertently cause false alarms.
18.6.2 Unsetting
 Unsetting of the AS shall be achieved by one or a combination of the following devices.  Other devices giving equivalent performance are permitted.
18.6.2.1. A mechanical key (complying with requirements of Annex 10 to this Regulation) which can be coupled with a centralised vehicle locking system comprising of at least 1,000 variants, operated from the outside.
18.6.2.2. Electrical/electronic device, e.g. remote control, with at least 50,000 variants and shall incorporate rolling codes and/or have a minimum scan time of ten days, e.g. a maximum of 5,000 variants per 24 hours for 50,000 variants minimum.
18.6.2.3. A mechanical key or an electrical/electronic device within the protected passenger compartment, with timed exit/entry delay.
18.7. Exit delay
 If the switching device for setting the