This standard specifies the technical requirements, test methods and markings for point-type smoke detectors. This standard applies to detectors installed in general industrial and civil buildings that work based on the principles of scattered light, transmitted light (photoelectric smoke) and ionization (ion smoke). Detectors installed in other environments that work based on other principles should also comply with this standard, except for special technical requirements that should be separately specified by relevant standards. GB 4715-1993 Technical requirements and test methods for point-type smoke detectors GB4715-1993 standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Point type smoke fire detectors
Technical requirements and test methodsfor point type smoke fire detectors1Subject content and scope of application
GB4715-93
Replaces GB471584
This standard specifies the technical requirements, test methods and markings for point type smoke fire detectors (hereinafter referred to as detectors). This standard applies to detectors installed in general industrial and civil buildings that work according to the principles of scattered light, transmitted light (photoelectric smoke sensing) and ionization principle (ion smoke sensing). Detectors installed in other environments that work according to other principles should also comply with this standard, except for special technical requirements that should be separately specified by relevant standards.
2 Reference standards
GB2423.1 Basic environmental test procedures for electric and electronic products Test A: Low temperature test method GB2423.3 Basic environmental test procedures for electric and electronic products Test Ca: Constant humidity and heat test method GB2423.10 Basic environmental test procedures for electric and electronic products Test Fc: Vibration (sinusoidal) test method GB2423.19 Basic environmental test procedures for electric and electronic products Test Kc: Sulfur dioxide test method for contact points and connectors GB6113 Electromagnetic interference measuring instrument
3 Technical requirements
3.1 When a fire occurs in the monitored area and its smoke parameters reach the preset value, the detector shall output a fire alarm signal and simultaneously activate the detector's alarm confirmation light or other displays with the same function. The display signal shall be maintained until it is manually restored. 3.2 The detector shall be equipped with a mesh with a maximum mesh size of no more than 1mm or take other measures to prevent insects from entering. 3.3 The detector shall withstand the tests specified in Chapter 4 of this standard and shall meet all the requirements of this standard. 4 Test methods
4.1 General requirements for tests
4.1.7 The tests specified in this standard are type tests, and the detector tests shall be carried out in accordance with the provisions of Appendix A. 4.1.2 The detector shall be inspected for appearance before testing. The test can only be carried out if it meets the following requirements: no corrosion, coating peeling, blistering, obvious scratches, burrs or other mechanical damage on the surface; a.
The insect prevention measures meet the requirements of Article 3.2;
The text symbols and signs are clear and the structure is not loose. c.
4.1.3 If there is no explanation in the relevant clauses, all tests shall be carried out under the following normal test atmospheric conditions: temperature
relative humidity
15~35C,
45%~75%;
86~106kPa.
Approved by the State Administration of Technical Supervision on April 10, 1993, and implemented on November 1, 1993
GB 4715-93
4.1.4 If a test requires the detector to be powered on, the detector shall be powered according to the requirements of the manufacturer or the fire alarm controller provided.
If there is no explanation in the relevant clauses, the tolerance of each test data shall be ±5%. For detectors with variable response thresholds, the response threshold of the detector shall be set at the maximum and minimum limits in the consistency test and tested separately; in the fire sensitivity test, the response threshold of the detector shall be set at the maximum limit and tested; in the remaining test items, the response threshold of the detector shall be set at the minimum limit and tested. 4.2 Test of response value
4.2.1 Test smoke
The test smoke is produced by smoldering defatted hickory peel, and the number of smoke particles with a particle size of 0.2 to 1.0 μm should not be less than 90% of the total number of particles. The test smoke can also be produced by a liquid paraffin aerosol generator. The selected test smoke must be used throughout the test process of all items. The test smoke should have reproducibility and stability in terms of particle size distribution. 4.2.2 Threshold test smoke box
The threshold test smoke box used for the test (hereinafter referred to as the smoke box) should meet the requirements of Articles 4.2, 4.5, 4.7 to 4.10 on the test of response value and the test requirements of orientation, voltage fluctuation, airflow, high temperature and ambient light, and should ensure that the test smoke is evenly distributed in the measurement interval. Figure 1 shows the layout of the measurement area, test instruments and detectors. Steam outlet end
Measurement area
≥0. 75 ~1. 75m
Air inlet end
Layout of detector and test instruments in smoke box Figure 1
1·-Screen; 2. Airflow velocity and airflow temperature measurement; 3 optical quantity (optical density meter); 4 test detector (installed on the cover); 5 ion smoke concentration meter ionization chamber (installed on the cover); 6- heating element; 7 smoke source 4.2.3 Test method
Install the detector in the smoke box according to its normal working position and connect it to the control and indicating equipment. Adjust the control and indicating equipment and the smoke box respectively so that the power supply voltage of the detector is 99%~101% of the rated working voltage (except for the voltage fluctuation test in Article 4.7), the airflow velocity near the detector is 0.2±0.04m/s (except for the airflow test in Article 4.8), the airflow temperature is 235℃ (except for the high temperature test in Article 4.9), the detector is in normal monitoring state, and after 15~20min, inject smoke into the smoke box according to the following requirements: dB/m (photoelectric smoke detector)
dB/m Am
0. 05min-1
Where: △m-一m Value increment, dB/m;
Ayy value increment, dimensionless;
At - time increment, min.
≤0.3min-1 (ion smoke detector) At
m and y values ​​are defined in 4.2.4.1 and 4.2.4.2 respectively. When the detector is activated, record the m value (photoelectric smoke detector) or y value (ion smoke detector). 324
The measurement of smoke concentration should be carried out near the detector. GB4715--93
Before each test, there should be no smoke in the smoke box and the detector. The rate of increase of all measured smoke concentrations in the smoke box should be relatively stable. Note: 1) The control and indicating equipment can use a fire alarm controller or a special test equipment. 4.2.4 Response threshold and test instrument
4.2.4.1 Optical method to measure response threshold
The response threshold of the photoelectric smoke detector is measured by an optical densitometer, which is represented by the light attenuation coefficient m (in B/) at the time when the detector is actuated.
Operating principle
The optical densitometer measures the smoke density by the principle that the light radiation energy decays exponentially after the light beam is affected by smoke particles. The light attenuation coefficient is represented by the following formula:
10 yuan P
Where: m---light attenuation coefficient, dB/m;
dThe optical measurement length of the test smoke, n,
The radiation power received when there is no smoke, w;
P-The radiation power received when there is smoke, W. Technical requirements
aThe optical measurement length is greater than 1.1m:
． The installation of the optical system should ensure that the photoelectric receiver cannot receive light with a scattering angle greater than 3° from the tested smoke particles. c. The effective radiation power should be greater than 50% when the wavelength of the light beam is within the range of 0.800~0.950μm, less than 10% when the wavelength is below 0.800um, and less than 10% when the wavelength is above 1.050um; d. Measurement error: For smoke concentrations between 0~2dB/m, the measurement error should not be greater than m·5%+0.02dB/m. Before each measurement, the reading of the measuring instrument must be compared with the reading (zero point) in clean air, and the measurement deviation should not be greater than 0.02 dB/m.
4.2.4.2 Ion method to measure the response threshold value
The response value of the smoke detector, that is, the smoke concentration at the time of the detector action expressed by the value (dimensionless), is measured using an ion smoke density meter.
Working Principle
The ion smoke density meter uses the air extraction method to continuously sample and continuously measure the smoke concentration. The ion smoke density meter is composed of an ionization chamber, a current amplifier and an air pump. Figure 2 is a schematic diagram of the ion smoke density meter ionization chamber. As shown in the figure, the air containing smoke particles is diffused into the "measurement volume" in the ionization chamber through the air pump. The air in the "measurement volume" is ionized by α rays. Therefore, when a voltage is applied between the two electrodes, an ionization current is generated. The ionization current changes due to the action of smoke particles, and the relative change of the ionization current is used as a measure of smoke concentration. The 3 values ​​measured by the ionization chamber of the ion smoke density meter conform to the following relationship: d.2n.y
Where: 1--ionization current when there are no smoke particles in the air; 1-ionization current when there are smoke particles in the air; d average particle size of smoke particles, m
number concentration of smoke particles, 1/m°;
ionization chamber constant, 1 m2
GB4715-93
The mechanical structure of the ionization chamber is shown in Figure 3. The tolerances are marked on its main dimensions. The dimensions without tolerances are recommended and are not rigidly specified. Technical requirements
a. Radioactive source
Nuclide: 241Am,
activity: 130kBq (3.5μci)±5%; average energy of α rays: 4.5MeV±5%. The cut section of the radioactive source should be tightly wrapped with a source seat, and the surface of the source should be protected by a precious metal layer. The diameter of the radioactive source disk: =27mm.
Ionization chamber
Figure 4 shows the current-voltage characteristic curve of the ionization chamber measured in clean air, and the measurement conditions are: air pressure: 101.3±1kPa (760mmHg); temperature: 25±2C;
relative humidity: 35%~～~75%.
Ionization chamber impedance (the inverse of the slope of the current-voltage characteristic curve): 1.9×10112±5%. The power supply voltage should ensure that a static current of 100pA flows through the measuring electrode. Figure 5 shows the working circuit of the ion smoke density meter. c. Current amplifier
Input resistance: R<10°2.
d. Suction pump
Gas flow rate: 30L/min±10%.
Air and smoke
Exhaust
Assembly plate
Insulation ring
Electronic device
Air and smoke
Protective ring
Measuring electrode
Measuring volume
α radiation source
Insulating material
Figure 2 Working principle of ion smoke concentration meter ionization chamber Inner grid
Air and smoke
Outer grid
Wind shield
Part number
Zhou Jin Shangcheng 6 shifts
Assembly plate
Multi-pin socket
Measuring electrode terminal
Viewing electrode terminal||tt| |Vacuum nozzle
Insulating plate
Protective ring
Measuring electrode
GB4715-93
Air range
Per 8 industry 05
Office 124±5
US s US
Figure 3 Ionization chamber structure diagram]
Ionization chamber parts list
Specifications and features
10 pins
Connect to ionization chamber power supply
Connect to amplifier or current measuring device
Polyamide
Polytetrafluoroethylene
Stainless steel
Stainless steel
Part number
Insulating ring
GB 4715-93
Fixing screw with peripheral knurled nut
Outer grid
Wind shield
Intermediate body
Butterfly pattern ring
Radioactive source base
Radioactive source
Specifications and features
With 6 air holes
Wire diameter 90.2mm
Inner eye width 0.8mm
Wire diameter 40.4mm
Inner eye width 1.6mm
There are 72 mm holes on the periphery
$27 mm Sealed
Figure 4 Ion smoke concentration meter ionization chamber current-voltage characteristic curve voltage to ground
Measurement electrode
Deep guard ring
Current measurement converter
Nickel-plated brass
Stainless steel
Stainless steel
Stainless steel
Stainless steel
Nickel-plated brass
Nickel-plated brass
See 4.2.4.2
The voltage output ratio is proportional to the ionization density current
Figure 5 Ion smoke concentration meter working circuit
4.3 Power-on test
4.3.1 Purpose
GB 4715--93
To test the stability of the detector under normal atmospheric conditions. 4.3.2 Method
First, measure the response value of the detector according to the provisions of Article 4.2. Then, make it run continuously for 45 days under normal monitoring. After the operation, measure the response value of the detector in the same measurement position as before the operation according to the provisions of Article 4.2. In the two measurements, the larger response threshold is represented by Ymax or mmx, and the smaller response threshold is represented by ymin or mmin. 4.3.3 Requirements
a. During the test, the detector should not send out a fault or fire alarm signal. The response value ratio Ymax:ymin or mmax1mm should not be greater than 1.6. 4.3.4 Test equipment
Use a smoke box.
4.4 Repeatability test
4.41 The repeatability of the detector response value is tested by the United States. 4.4.2 Method bZxz.net
According to the provisions of Article 4.2, measure the response threshold 6 times continuously at any position of the detector's normal working position. The maximum value of the 6 response thresholds is represented by 3max or mx, and the minimum value is represented by 3m or mmin. 4.4.3 Requirements
The response threshold ratio ymaxymn or mmxmmin should not be greater than 1.6. 4.4.4 Test equipment
Use a smoke box.
4.5 Azimuth test
4.5.1 The smoke inlet performance of the detector in different orientations shall be tested during the test and the "most favorable" and "most unfavorable" response orientations of the detector shall be determined. 4.5.2 Methods
According to the provisions of 4.2, the response readings shall be measured 8 times at different orientations of the detector. After each measurement, the detector shall be rotated 45° around its vertical axis in the same direction. The orientations of the maximum and minimum response readings of the detector shall be recorded. In the following tests, these two positions are called the "most unfavorable" and "most favorable" positions. The maximum response value is represented by ymux or mmax, and the minimum response threshold is represented by ymin or mmin. 4.5.3 Requirements
The response threshold ratio 3x:m or mnx:mmn should not be greater than 1.6. 4.5.4 Test equipment
Use a smoke box.
4.6 ~ Conformity test
Check the consistency of the detector response value. 4.6 .2 Method
Number the 18 detectors in sequence from 1 to 18, and measure the response threshold at the "most unfavorable" orientation of the detector in accordance with the provisions of Article 4.2. For detectors with variable response thresholds, the response thresholds of the detectors should be set at the maximum and minimum limit values ​​for separate tests. Among the 18 detectors, the maximum response reading is represented by 3max or mmx, and the minimum response reading is represented by ymn/mmin. For a group of detectors with variable response thresholds, when set at the maximum limit value, the maximum response reading is represented by ymax(1 or mmax(1), and the minimum response reading is represented by ymin1) or mmuin(1). When set at the minimum limit value, the maximum response threshold is represented by 3max(2) or mmax(2), and the minimum response value is represented by ymin2) or mmin2. 4.6.3 Requirements
4.6.3.1 For fixed response threshold detectors GB 4715—93
a. The response threshold ratio ymex:Jmin or mmx:mmin shall not be greater than 1.6; b. The minimum response threshold ymin shall not be less than 0.2, mmin shall not be less than 0.05dB/m; the maximum response threshold ymax shall not be greater than 3.0, mmax shall not be greater than 2.0dB/m.
4.6.3.2 For variable response threshold detectors a. The response threshold ratio ymax(1):Ymin(1) or mmax(1):mmin(1) and Y max(2):ymin(2) or mmax(2):mmin(2) should not be greater than 1.6;
b. The minimum response thresholds ymin(1) and ymin(2) should not be less than 0.2, mmin(1) and mmin(2) should not be less than 0.05dB/m; the maximum response thresholds ymax(1) and ymax(2) should not be greater than 3.0, mmax(1) and mmax(2) should not be greater than 2.0dB/m. 4.6.4 Test equipment
Use a smoke box.
4.7 Voltage fluctuation test
4.7.1 Purpose
To test the adaptability of the detector to work under the rated working voltage fluctuation conditions. 4.7.2 Method
The detector is tested according to 4.2 stipulates that in the "most unfavorable" position, the rated working voltage is reduced by 15% and increased by 10% or the response threshold is measured according to the upper and lower limits of the rated working voltage specified by the manufacturer. Compared with the response threshold of the detector in the consistency test, the largest response value among the three is represented by ymax or mmax, and the smallest response threshold is represented by ymin or mtnin.
4.7.3 Requirements
The response threshold ratio ymax:ymm or mmax:mmin should not be greater than 1.6. 4.7.4 Test equipment
Use a smoke box.
4.8 Airflow test
4.8.1 Purpose
To test the ability of the detector to resist airflow interference. 4.8.2 Method
4.8.2.1 Response performance test
Under the condition of wind speed of 0.2±0.04m/s around the detector, the response value shall be measured in the most unfavorable and most favorable directions of the detector in accordance with the provisions of Article 4.2, and expressed as y(0.2)max and y(0.2)min or m(0.2)ma and m(0.2)min respectively (the subscript 0.2 indicates the wind speed is 0.2±0.04m/s).
Repeat the above test under the condition that the wind speed around the detector is 1±0.2m/s. The response thresholds are represented by y(1.0>max and y(1.0)min or m(1.0)mx and m(1.0)min respectively (the subscript 1.0 indicates that the wind speed is 1.0±0.2m/s). 4.8.2.2 False alarm test
Install the detector in the smoke box containing only clean air in its normal working position, taking the "most favorable direction", and connect the control and indicating equipment. Adjust the air flow speed in the smoke box to 5±0.5m/s for 5min, and then suddenly increase to 10±1m/s for 2s (the photoelectric smoke detector is not subject to false alarm test). 4.8.3 Requirements
The response threshold should meet the following requirements:
y(0.2mx+0.2mim1.6,
y(1. 0)max +y(1. 0)min
GB4715-93
mo.2)mztmco.2)min≤1. 6;
m(.0)max + m(1.0)min
h. During the false alarm test, the detector should not send out a fault or fire alarm signal. 4.8.4 Test equipment
Use a smoke box.
4.9 High temperature test
4.9.1 Purpose
To test the adaptability of the detector to be used in a high temperature environment. 4.9.2 Method
Install the detector in the smoke box in its normal working position and the "most unfavorable" orientation, and connect the control and indicating equipment to put it in a normal monitoring state. The initial temperature in the smoke box is 23±5°C. Adjust the temperature in the smoke box to 50±2°C at a heating rate of no more than 1°C/min, and maintain it for at least 2h. Then measure the response threshold at this high temperature as specified in Article 4.2. Compared with the response threshold of the detector in the consistency test, the larger response threshold is used. ymax or mmax, and the smaller response value is yunim or maiu.
4.9.3 Requirements
The response threshold ratio ymax:3min or mmax;mmin should not be greater than 1.6. 4.9.4 Test equipment
Use a smoke box.
4.10 Ambient light test
4.10.1 The stability of the performance of the photoelectric smoke detector under the action of ambient light shall be tested. 4.10.2 Methods
Install the detector in the smoke box in its normal working position and the "most unfavorable" orientation, and connect the control and indicating equipment to put it in the normal monitoring state.
First, each lamp of the flash device (4.10.4) shall be turned on and off 10 times in a fixed procedure of "power on (10s)-power off (10s)\. Then repeat the same process for each pair of lamps installed opposite to each other. Then, turn on the four lights at the same time for at least 1 minute, and then measure the detector response value according to the provisions of 4.2.
Rotate the detector 90° in any direction around its vertical axis and repeat the above test process. Compare the detector response threshold measured each time with the detector response threshold in the consistency test, where the larger response threshold is represented by mmax and the smaller response threshold is represented by mmn. 4.10.3 Requirements
a. During the test, the detector should not send out a fault or fire alarm signal: b. The response threshold ratio mmax:mmin should not be greater than 1.6. 4.10.4 Test equipment
The test equipment is a special flash device in the shape of a regular hexahedron (see Figure 6). The inner side of the four closed surfaces is lined with smooth aluminum foil. Four ring fluorescent lamps are fixed on the inner side of the four closed surfaces, each with a power of 30W, a color temperature of 3200~4200K, and a diameter of about 380 mm. The installation position of the fluorescent lamp tube shall not affect the measurement of the response threshold. The detector is installed at the center of the top surface of the regular hexahedron so that light can shine on the detector from the top, bottom and both sides. The electrical circuit of the fluorescent lamp shall not interfere with the detector. In order to stabilize the output light, the lamp tube should be aged for 100 hours and the lamp tube should be scrapped after 2000 hours of use.
4.11 Vibration test
4.11.1 Purpose
E(D,C)
GB 4715
Smoke detector
Bottom surface ABFE
Side surface AEHD
Side surface BFGC
Smoke flow direction
Dispersed side surface: ABCD
Detector socket
Top surface DCGH For installing lamps
Figure 66 Flash device diagram
To test the adaptability of the detector to withstand vibration and the integrity of its structure. 4.11.2 Method
Install the base of the detector on the vibration table in its normal working position. Connect the detector to the control and indicating equipment and put it in normal monitoring state. Perform a frequency cycle in the frequency cycle range of 10~150~10Hz on three mutually perpendicular axes in turn, with an acceleration amplitude of 9.81m/s2 and a sweep rate of 1 octave/min to check whether there is a dangerous frequency. If there is a dangerous frequency, the detector is subjected to a fixed-frequency vibration test with an acceleration amplitude of 9.81m/s2 and a duration of 90±1min on each dangerous frequency of the three mutually perpendicular axes; if there is no dangerous frequency, a fixed-frequency vibration test with a frequency of 150Hz, an acceleration amplitude of 9.81m/s2 and a duration of 90±1min is performed on the three mutually perpendicular axes. Then, according to Article 4.2, measure the response threshold in the "most unfavorable" orientation and compare it with the response threshold of the detector in the consistency test, where the larger response threshold is represented by ymax or mmax, and the smaller response threshold is represented by ymin or mmin. 4.11.3 Requirements
During the test, the detector should not send out a fault or fire alarm signal; after the test, the detector has no mechanical damage and loose fastening parts; the response threshold ratio ymax:Ymin or mmax:mmin should not be greater than 1.6. 4.11.4 Test equipment
The test equipment (vibration table and fixture) should comply with Article 3.1 of GB2423.10. 4.12 Damp heat test
4.12.1 Purpose
To test the adaptability of the detector for use in a damp and hot environment. 4.12.2 Methods
After drying the two detectors and their bases in a drying oven at a temperature of 40±5℃ for 24h, move them to the damp heat test chamber immediately and connect the detectors to the control and indicating equipment to put them in a normal monitoring state. Adjust the condensation heat test chamber so that the detectors are kept at a temperature of 40±2℃ and a relative humidity of 90% to 95% for 96h. Then take out one detector and immediately measure the response value in the "most unfavorable" position according to the provisions of Article 4.2. After the other detector is taken out of the damp heat test chamber, it is placed in an environment with a temperature of 15-25℃ and a relative humidity of less than 70% for 72 hours. Then, according to the provisions of Article 4.2, the response value is measured in the "most unfavorable" direction, and the response thresholds of the two detectors measured are compared with the response thresholds of the two detectors in the conformity test. The larger response threshold is represented by Ymx or mmax, and the smaller response threshold is represented by Ymin or mmin. In the damp heat test chamber and when transitioning from one environment to another, condensation should not appear on the surface of the detector. 4.12.3 Requirements
a. During the test, the detector should not send out a fault or fire alarm signal; b. After the test, the detector should not have damage to the coating and corrosion; c. The response threshold ratio Vanx:ymin or mmax:mmin should not be greater than 1.6.4.12.4 Test equipment
The test equipment (wet heat test chamber) shall comply with the provisions of Chapter 2 of the national standard GB2423.3. 4.13 Impact test
4.13.1 Purpose
To test the adaptability of the detector to non-repetitive mechanical impacts and the integrity of its structure. 4.13.2 Method
Install the detector and the base in the center of the bottom surface of the wooden beam of the impact test equipment (see Figure 7) in their normal working position, and turn on the control and indicating equipment to put it in normal monitoring state. Adjust the test equipment so that a cylindrical steel block with a mass of 1kg falls vertically from a height of 700mm along the guide device to the center of the top surface of the wooden beam, with an impact area of ​​18cm±10%, and falls continuously for 5 times. After the test, according to the provisions of 4.2, the response value is measured at the "most unfavorable" orientation and compared with the response threshold of the detector in the consistency test, where the larger response threshold is represented by ymax or mmax, and the smaller response threshold is represented by ymin or mmin. 4.13.3 Requirements
a. During the test, the detector should not send out a fault or fire alarm signal; b. After the test, the detector should have no mechanical damage and loose fastening parts; C. The response threshold ratio yaux:Ymin or mmx:mmin should not be greater than 1.6. 4.13.4 Test equipment
The test equipment (see Figure 7) is a wooden beam support device. The wooden beam can be made of pine wood with a cross-sectional size of 100mm×50mm. The narrow side of the wooden beam is fixed on two pine wood legs with a width of 50mm. The legs are placed on a flat concrete floor and have sufficient height to prevent the detector from touching the ground. The legs are at right angles to the longitudinal axis of the wooden beam, and the center distance between the two legs is 900mm. 333
4.14 Collision test
4.14.1 Purpose
GB4715-93
Figure? Impact test equipment
a-1kg steel block b-guide rod tc-sample wooden beam nut and gasket: e-wooden support foot; f-detector
Test the adaptability of the detector to withstand mechanical collision. 4.14.2 Method
This distance is guaranteed
The detector does not change the floor
Install the detector and the base on the rigid horizontal mounting plate of the collision test equipment in its normal working position (see Figure 8), and turn on the control and indicating equipment to put it in normal monitoring state. The detector should be powered on for at least 15m before the test. in. Adjust the collision test equipment so that the center of the hammer impact surface can hit the detector from the horizontal direction and align it with the part of the detector that is most vulnerable to damage. Then, hit the detector with a hammer speed of 1.5±0.125m/s and a collision kinetic energy of 1.9±0.1J. After the collision, according to the provisions of Article 4.2, measure the response threshold of the detector in the "most unfavorable position" and compare it with the response threshold of the detector in the consistency test, where the larger response threshold is represented by Ymax or mmx, and the smaller response threshold is represented by Ymin or mmin. 4.14.3 Requirements
a. During the test, the detector should not send out a fire alarm signal; after the test, the detector and the base, and the base and the mounting plate should not be loose or displaced; b.
The response threshold ratio Ymax:Ymin or mmax:mmin should not be greater than 1.6. 4.14.4 Test equipment
The main body of the test equipment (see Figure 8) is a pendulum mechanism. The hammer of the pendulum is made of hard aluminum alloy AICu.SiMg (solid solution and aging treatment), and its shape is a hexahedron with an inclined collision surface. The pendulum of the hammer is fixed on a steel wheel hub with a ball bearing, and the ball bearing is installed on a fixed steel shaft of a hard steel frame. The structure of the hard steel frame should ensure that the pendulum can rotate freely when the detector is not installed. The overall dimensions of the hammer are 94mm long, 76mm wide and 50mm high. The angle between the chamfer of the hammer and the longitudinal axis of the hammer is 60±1°. The outer diameter of the pendulum of the short head is 25±0.1mm, and the wall thickness is 1.6±0.1mm. The radial distance between the longitudinal axis of the hammer and the axis of rotation is 305mm, and the axis of the pendulum of the hammer must be perpendicular to the axis of rotation. The steel wheel hub with an outer diameter of 102mm and a length of 200mm is concentrically assembled on a steel shaft with a diameter of 25mm. The accuracy of the diameter of the steel shaft depends on the size tolerance of the bearing used.
Two steel counterweight arms with an outer diameter of 20mm and a length of 185mm are installed in the direction opposite to the steel wheel hub and the swing rod, and the extended length is 150mm. An adjustable counterweight block is installed on the two counterweight arms to balance the head and the counterweight arm. A spoke alloy pulley with a thickness of 12mm and a diameter of 150mm is installed on the end of the steel wheel hub. A cable is wound around the pulley, one end of the cable is fixed on the pulley, and the other end is tied to a working weight.1mm. The radial distance between the longitudinal axis of the hammer head and the axis of rotation is 305mm, and the axis of the swing rod of the hammer head must be perpendicular to the axis of rotation. The steel wheel hub with an outer diameter of 102mm and a length of 200mm is concentrically assembled on a steel shaft with a diameter of 25mm. The accuracy of the diameter of the steel shaft depends on the size tolerance of the bearing used.
Two steel counterweight arms with an outer diameter of 20mm and a length of 185mm are installed in the direction opposite to the steel wheel hub and the swing rod, and the extended length is 150mm. An adjustable counterweight block is installed on the two counterweight arms to balance the head and the counterweight arm. A spoke alloy pulley with a thickness of 12mm and a diameter of 150mm is installed on the end of the steel wheel hub. A cable is wound around the pulley, one end of the cable is fixed on the pulley, and the other end is tied to the working hammer.1mm. The radial distance between the longitudinal axis of the hammer head and the axis of rotation is 305mm, and the axis of the swing rod of the hammer head must be perpendicular to the axis of rotation. The steel wheel hub with an outer diameter of 102mm and a length of 200mm is concentrically assembled on a steel shaft with a diameter of 25mm. The accuracy of the diameter of the steel shaft depends on the size tolerance of the bearing used.
Two steel counterweight arms with an outer diameter of 20mm and a length of 185mm are installed in the direction opposite to the steel wheel hub and the swing rod, and the extended length is 150mm. An adjustable counterweight block is installed on the two counterweight arms to balance the head and the counterweight arm. A spoke alloy pulley with a thickness of 12mm and a diameter of 150mm is installed on the end of the steel wheel hub. A cable is wound around the pulley, one end of the cable is fixed on the pulley, and the other end is tied to the working hammer.
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.