First, construction preparation
1.1 Technical preparation
1. Review the drawings before construction.
2. The construction organization design (construction plan) should be prepared before the construction, and reported to the first-level technical person in charge for review and approval.
3. Before the construction, technical disclosure should be carried out to clarify the construction methods and quality standards.
1.2 Main materials
Speakers, amplifiers, broadcast cabinets, cables and wires, cable clamps, bolts, pipes, profiles, etc.
1.3 Main equipment
Construction equipment: lifts, electric welders, cutting machines, pipe benders, electric drills, grinders, etc.
Test instruments: digital multimeter, sound source, sound level meter, oscilloscope, low frequency signal generator, distortion measuring instrument, walkie-talkie, etc.
1.4 Working conditions
Before installing the public address and emergency broadcast system, the following conditions should be met:
1. Construction of the engine room and weak electric shaft has been completed;
2. The pre-embedded pipe and the reserved hole meet the design requirements;
3. After the equipment room construction is completed, the equipment room environment, power supply and grounding installation have been completed, and the installation conditions are available;
Second, material quality control Public broadcasting and emergency broadcasting system equipment, materials entry and acceptance requirements in addition to comply with relevant regulations:
1. The technical parameters of the speaker (box), power amplifier, broadcast cabinet and power supply shall comply with the design and product technical requirements, and shall provide the production business license and relevant test certificate of the manufacturer.
2. All kinds of cables have warranty information such as the factory certificate.
Third, the construction process
3.1 Construction process
Technical data review → equipment room installation → line laying → speaker installation → system test
3.2 Construction points
1. The room layout of the equipment room is installed according to the design requirements.
A. The installation of broadcasting room equipment should be convenient for maintenance. The equipment should not be excessively dense. There should be a wide passage between the console and the rack. The clearance between the equipment and the floor-standing broadcasting equipment should not be less than 1500mm. The equipment and equipment are juxtaposed. When arranging, it should be ensured that the interval is easy to pass, and should not be less than 1000mm;
B. The equipment should be installed smoothly and correctly, and the floor-standing equipment should be fixed by anchor bolts or reinforced with angle steel on the back wall;
C. After the equipment is installed, the verticality should be adjusted and the vertical error should be no more than 1.5/1000.
2. Route laying
A. Apply a shielded cord to the feed of the audio signal input.
a) A dedicated shielded cord must be used for the microphone output. For a length between 10m and 50m, a double-core shielded cord should be used for low-impedance balanced input connection. If there is a microphone adapter socket, the contact characteristics must be good.
b) (2) The long-distance connected microphone cable (more than 50m) must be low-impedance (200Ω), balanced transmission connection method, it is best to use four-core shielded wire twisted pair and penetrate the steel pipe laying.
c) The connection between the mixer and all peripheral equipment requires a single-core (unbalanced) or two-core (balanced) shielded cord connection.
B. The power output feed refers to the connection cable between the power amplifier output and the speaker box, and the cross section and high or low impedance are selected according to the distance.
a) Halls, dance halls and other indoor sound reinforcement systems should use low-impedance output. They should be laid with a soft-fired wire with a cross-sectional area of ​​2 to 6 mm2. The DC resistance of the bidirectional calculated length should be less than 0.02 to 0.01 of the speaker impedance.
b) (2) Outdoor sound reinforcement, stadium sound reinforcement building background music and hotel room broadcasting should use high-impedance constant voltage transmission (70V or 100V), and the feeder should adopt double-core PVC multi-strand flexible wire.
c) (3) The broadcast line of multiple sets of hotel rooms should be equipped with a pair of feeders for each set of programs, but not a common ground line to avoid interference between program signals.
C. Power supply line selection (single-phase, three-phase, automatic voltage regulator), isolation transformer (1:1) should be used. When the total power consumption is <10kVA, use single-phase 220V; when the total power consumption is >10kVA, use The three-phase power supply is divided into three output 220V power supplies. When the voltage fluctuation exceeds +5% or 10%, an automatic voltage regulator should be used to ensure the normal operation of each system equipment. All feeders should be laid through pipes. The line construction should be carried out in accordance with the "Technical Standards for Construction Electrical Engineering" ZJQ08 - SGJB303 -2003.
D. Grounding and lightning protection shall be installed and installed according to the requirements of standard specifications.
a) A special grounding wire should be provided, and the grounding wire should not be shared with lightning protection grounding or power supply grounding.
b) The audio ground must be a single point and must not form an audio ground loop.
3. Speaker installation
A. The sound reinforcement speaker system should be mounted on the surface. If it is concealed, the sound-transparent opening of the decorative surface should be large enough. The size of the sound-permeable material or masked strip should be small enough relative to the wavelength of the main sound-amplifying frequency band.
B. It should be firm whether it is mounted or concealed, and no mechanical noise should be generated due to vibration.
C. The background music speaker (box) used in conjunction with the fire accident broadcast shall not be equipped with a volume adjustment or control switch at the site.
D. The sound characteristics measurement method of the public address system of the sound reinforcement system is carried out according to the relevant standards. The hall sound reinforcement system implements the “Measurement Method of Sound Enhancement Characteristics of the Hall†GB/T4959-1995, and the sound reinforcement system of the dance hall performs the acoustics of the sound reinforcement system of the dance hall. Characteristic index and measurement method "WH0301-93", the stadium will implement the Ministry of Construction standard "Sports Acoustic Design and Measurement Regulations" JGJ-T131-2000.
4. System testing After the installation of the public address and emergency broadcast system is completed, system testing and functional testing should be performed.
A. System testing includes the following:
a) The system's input and output imbalance, audio cable laying and grounding form ensure that the installation quality meets the design requirements and the impedance matching between the devices is reasonable;
b) The sound release system should be reasonably distributed and meet the design requirements;
c) The technical indicators of the highest output level, output signal to noise ratio, sound pressure level and bandwidth should meet the design requirements;
d) assessing the acoustics of the system through subjective evaluation of loudness, timbre and sound quality;
B. Functional testing should include:
a) Business promotion, background music and public paging.
b) When emergency broadcast and public broadcasting share equipment, the emergency broadcast is controlled by the fire-fighting extension and has the highest priority. In the event of fire and emergency, it should be able to be forced to switch to emergency broadcast and broadcast at maximum volume; emergency broadcast function Testing is carried out in accordance with relevant regulations;
c) The power amplifier should be redundantly configured, and when the host fails, the standby machine is automatically put into operation according to the design requirements;
d) The public broadcasting system shall be controlled by division, and the division of divisions shall not contradict the division of fire divisions.
Fourth, finished product protection
1. When laying the pipeline, keep the wall, ceiling and floor clean and complete; when repairing iron paint, do not pollute the building.
2. When constructing high stools, do not collide with walls, corners, doors, windows, or even stand tall against the wall. The high stools should have a bandage to prevent scratching the floor and slipping.
3. When piping the cast-in-place concrete floor, be careful not to step on the steel bars. When constructing concrete for civil construction, special personnel should be guarded to avoid damage to the piping and boxes and boxes when vibrating; in case of pipeline damage, repair in time.
4. In the construction of the equipment room, protective and dustproof measures must be taken to avoid collision and damage to the equipment.
5. The door of the sound control room should be locked. Non-installed personnel are not allowed to enter without permission. A special person must be on duty before the project is handed over.
V. Construction safety and environmental protection measures
1. Measures such as maintenance safety, danger prevention, and fire prevention should be taken at the construction site; if conditions permit, closed management should be implemented on the construction site.
2. If the construction site may cause damage to adjacent buildings, structures and special operating environments, safety precautions shall be taken.
3. During construction, the laws and regulations concerning environmental protection and safe production shall be observed, and measures shall be taken to control and deal with various dust, exhaust gas, waste water, solid waste, noise and vibration of the construction site.
6. System testing Public broadcasting and emergency broadcasting system testing shall meet the following requirements:
1. The system's input and output imbalance, audio cable laying and grounding form ensure that the installation quality meets the design requirements, and the impedance matching between the devices is reasonable;
2. The sound release system should be distributed reasonably and meet the design requirements;
3. The technical indicators of the highest output level, output signal to noise ratio, sound pressure level and bandwidth should meet the design requirements;
4. Evaluate the acoustics of the system by subjective evaluation of loudness, timbre and sound quality;
5. Functional testing should include:
a) Business promotion, background music and public paging.
b) When emergency broadcast and public broadcasting share equipment, the emergency broadcast is controlled by the fire-fighting extension and has the highest priority. In the event of fire and emergency, it should be able to be forced to switch to emergency broadcast and broadcast at maximum volume; emergency broadcast function Testing is carried out in accordance with relevant regulations;
c) The power amplifier should be redundantly configured, and when the host fails, the standby machine is automatically put into operation according to the design requirements;
d) The public broadcasting system shall be controlled by division, and the division of divisions shall not contradict the division of fire divisions.
Seven, acceptance project
Tubular Stranding Machine
Tubular and planetary stranding machines for production of steel wire ropes.
Tubular rotor supported by bearing, bearing lubrication by centralized circulating oil.
Planetary cages supported by bearing or under roller, with back twist.
Lay length optional by gearbox or by electrical system.
Machine design customized.
Tubular Strander,Stranding Machine,Wire Stranding Machine,Tubular Stranding Machine
ROYAL RANGE INTERNATIONAL TRADING CO., LTD , https://www.royalrangelgs.com