Industrial safety standards require installation of a respective sound signaling device, which is actuated in case of alarm, emergency or danger for personnel, involved in modern industrial processes.
Explosion-proof loudspeakers series PGZ-GROM2 are intended for sound alarm and warning and are placed in stationary and movable transport vehicles. Explosion-proof loudspeakers have one tap hole M25x1.5 as per GOST 24705-2004 and may be completed with a cable gland depending on the type of connected cable. The enclosure is made from antistatic aluminum alloy. Explosion-proof loudspeakers series PGZ-GROM2 are intended for application in potentially hazardous areas with explosive gases and dust.
Upon the customer‘s request, the loudspeakers can be completed with explosion-proof speech interface unit, which allows storing pre-recorded messages. Explosion-proof loudspeaker is intended for continuous round-the-clock operation (transmission of pre-recorded information on safety assurance activities, on command). Selected speech message or sound signal is transmitted continuously until de-energizing of the loudspeaker or control signal deactivation. The speech interface unit is connected with PGZ-GROM2 loudspeaker by a cable up to 30 meters long, which enables to arrange it in a convenient place for setting and maintenance. Recording of speech messages is performed as per customer‘s specification.
Connection to speech interface unit /BS to the computer allows the customer: - to transmit messages recorded in the digital data storage of the loudspeaker with pauses between messages; - to transmit new speech messages using microphone or out of computer storage memory without recording them in data storage.
By default, the device is supplied without mounting bracket. To add mounting bracket to the assembly, /SKOBA option must be specified in the marking when ordering.
Scope of application – outdoor and indoor hazardous areas as per explosion protection marking, GOST 30852.13-2002 (IEC 60079-14:1996), dangerous production facilities of I, II, III, IV hazard class supervised by Rostechnadzor and national technical supervision bodies of the CIS countries.
Low-resistance loudspeakers intended for operation with equipment with low-voltage power supply.
Transformer acoustic systems for transmission of messages are efficient in large rooms. Permitted for installation at the distance of hundreds of meters from the power amplifier (also with transformer output) without loss of useful signal.FORMATION OF MARKING
|PGZ-GROM2||-||X||-||Х||-||Х||/||Х||– TU 3400-005-72453807-07|
|Power W: 5, 15 or 25|
|Version: 16 (16 Ohm); 100 (100V)|
|Cable gland dimension type|
|Options, accessories and versions|
Example: PGZ-GROM2-25-100-KNV2N-TU 3400-005-72453807-07
According to GOST R IEC 60073-2000, sound signals may be applied in cases when:
– it is required to draw an operator‘s attention;
– coded information will be short, simple and transient;
– the information requires immediate time-dependent answer;
– application of visual signal is limited;
– the situation is critical and it requires additional or redundant information.
The sound signal may consist of pure or complex tones (not more than 5 signals). The sound signal must be audible and easily recognized by operators and people in the set area of signal reception and at set background noise conditions. Signals must be different from the emergency signal, as per ISO 8201 part 7.
Sound signals of different types must be clearly distinguishable from each other.
Limited audibility of signals must be also taken into account in cases, when employees wear protective devices or earphones, as well as people with hearing impairment.
General rules of identification of sound signals when coding the information:
1. Continuous, sharply intensifying sound means danger (danger to the safety of people or equipment), critical (process status), malfunction (equipment status).
2. Intermittent sound with constant interval means attention (safety of people or equipment), transient (process status), transient (equipment status).
3. Continuous sound with permanent level means safety (safety of people or equipment), normal (process status), normal (equipment status).
4. Interchanging sounds have special meaning, as per technological documentation.
5. Other sounds do not have special meaning and cannot be easily identified by operators, not desirable.
To prevent sound overpressure of operators, it is required to use minimum amount of sounds of different kind in this application.
Intermittent sound signal may be used in some particular cases (for example, in case of change of dangerous or transient state to a safe state).
Sound signals should not be applied in case of safe state (silence).