Operating environment gas detection and alarm instrument common technical requirements
1 Subject and Scope
This standard specifies the terms of operating environment with gas detection alarm device, classification, technical requirements, test methods, inspection rules and signs.
This standard applies to the operating environment of flammable gases (including methane), toxic gas and oxygen detection alarm.
2 reference standards
GB 2 421 electrician electronic products, basic environmental testing procedures for General Provisions
GB 3836.1 explosive for use in explosion-proof electrical equipment General requirements
GB 3836.2 explosive atmospheres - Flameproof explosion-proof electrical equipment electrical equipment "d"
GB 3836.4 explosive atmospheres the nature of the explosion-proof electrical equipment safety circuits and electrical equipment "i"
GB 4798.10 electric and electronic products application environment conditions Introduction
GB 4857.5 transport packages - Basic test the vertical impact drop test conditions
5 274 GB of gas analyzer calibrated with gas mixtures - Gravimetric method
GB 5275 Gas analysis Preparation of calibration gas mixtures and permeation method
3 Terms
3.1 The detector
By the sampling device, the sensor and preamplifier circuit components.
3.2 Sensor
The concentration of the sample gas is converted into components of the measurement signal.
3.3 Indicator
Indicates that the components of the gas concentration measurement results.
3.4 alarm
Gas concentrations meet or exceed the alarm set value, the alarm signal components, commonly have a buzzer, light.
3.5 The scope of testing
Alarm under the experimental conditions to measure the range of the measured gas concentrations.
3.6 The detection error
The maximum error between the indicated value and the standard value allowed under the experimental conditions, alarm instrument with standard gas calibration.
3.7 alarm error
Under the experimental conditions, the alarm device with standard gas calibration, alarm allowed the maximum error between the indicated value and alarm settings.
3.8 alarm settings
According to the laws and regulations or standards or site conditions, alarm instrument pre-set alarm concentration.
3.9 Repeatability
The same alarm device, the same test objects in a short time under the same conditions repeat determination, all indicate the degree of coincidence between the values.
3.10 Stability
Under the experimental conditions, the alarm device to maintain the performance the extent of changes in the working state after a certain time.
3.11 response time
Under the experimental conditions, contact with the measured gas detector to reach stability indicated value of the time. Typically, reading to stabilize the indicated value of 90% of the time as the response time.
3.12 recovery time
Under the experimental conditions, from the detector from the measured gas to restore the time of the surveillance state. Typically, reading recovery to stable indicates the value of 10% of the time as the recovery time.
3.13 monitor the state
The alarm emits working condition before the alarm.
3.14 alarm state
Alarm status of the instrument alarm.
3.15 Fault Status
Alarm occurrence of state failure does not work properly.
3.16 Zero Gas
Without measured gas or other interfering gases, cleaner air or nitrogen.
3.17 standard gas
Gas composition, concentration and accuracy are known.
4 Classification
4.1 according to the detected object classification, flammable gases (including methane), the alarm detector, toxic gas detection alarm, oxygen detection alarm.
4.2 Classification according to detection theory, combustible gas detection with catalytic combustion type, type semiconductor, the thermal conductivity type, and infrared absorption; toxic gas detection Electrochemical type, semiconductor type; oxygen detection electrochemical type.
4.3 use classification, portable and fixed.
4.4 Classification of establishments, the conventional type and explosion proof.
4.5 classified by function, gas detector, gas alarm apparatus and gas detection alarm.
4.6 according to sampling classification, diffused and pump suction.
5 Technical requirements
5.1 structural requirements
5.1.1 The gas detector should be detector and indicator composed of two parts; gas alarm device by the detector and the alarm of two parts; gas detection alarm device should be detected, indicator and alarm system consists of three parts.
5.1.2 combustible gas alarm detector's detection range lower limit is zero, the limit should be greater than or equal to the lower explosive limit; toxic gas detection alarm detection range lower bound of zero, the limit should be greater than three times the maximum allowable concentration; oxygen detection and alarm The instrument used for hypoxia detection, the minimum detection range is zero, the upper limit should be greater than 25% volume percent concentration for oxygen leak detection, the lower limit is zero, the limit should be greater than 40% volume percent concentration.
5.1.3 Portable and mobile alarm device should be small size, light weight, easy to carry or move.
5.1.4 Fixed alarm device, the detector should have a weather-proof, sand, insects and structure, easy installation. Indicates that the alarm should be easy to install, operate and monitor.
5.1.5 should be corrosion-resistant material instrument or anti-corrosion treatment of the surface of the instrument, its easy to fall off the painting and coloring.
5.1.6 instrument in working condition should be easily identifiable.
5.1.7 The instrument should be easy to correction.
5.1.8 for there are flammable, explosive gas place with explosion-proof performance, comply with the GB 3836.1 and GB 3836.2 and GB 3836.4, and obtained the explosion-proof inspection certificate.
5.1.9 Alarm and detection alarm should have an effective warning device.
5.2 Performance requirements
5.2.1 The detection error should be consistent with the requirements of Table 1:
Table 1 Detection Error
5.2.2 The alarm error should be consistent with the requirements of Table 2:
Table 2 alarm error
5.2.3 The repeatability shall meet the requirements of Table 3:
Table 3 Repeatability
5.2.4 Stability
According to the 6.5 test, the instrument must meet the requirements of 5.2.1-5.2.2.
5.2.5 Instrument posture
When you press the 6.6 test instrument shall comply with the requirements of 5.2.1-5.2.2.
5.2.6 Vibration of impact
Testing according to 6.7, the instrument shall comply with the requirements of 5.2.1-5.2.2.
5.2.7 detection response time and alarm response time
a combustible gas detection alarm device during the trial of 6.9 and 6.10 set forth in the detection and alarm response time must be less than in the 30s;
(b) during the trial of 6.9 and 6.10 set forth in hazardous gas detection alarm, detection and alarm response time must be less than in the 60s;
hypoxia alarm detector test by the provisions of 6.9 and 6.10, testing the response time must be less than 20s, alarm response time must be in less than 5s.
Oxygen leak detection alarm device when tested according to the provisions of 6.9 and 6.10, the detection and alarm response time must be less than in the 20s.
5.2.8 Temperature of the impact
(a) When tested according to the provisions in 6.11.1, the detection error detection alarm and alarm error should meet the requirements of 5.2.1-5.2.2;
(b) When tested according to the provisions in 6.11.2, the detection response time of the alarm detector and alarm response time should be provided for in 5.2.7.
5.2.9 the impact of supply voltage
Alarm detector 6.12 in the tests specified, within the error range of the detection error and alarm error should be prescribed in 5.2.1-5.2.2.
5.2.10 toxic gas detection alarm should test the impact of interfering gases.
6 Test methods
6.1 The test conditions
In addition to the special provisions of the conditions of the test site according to GB 2 421 practice test atmosphere temperature to 15-35 ° C, relative humidity of 45% -75%, pressure 86-106kPa.
When the alarm detector to enter the work state and you can start the test after a settling time specified by the manufacturer. Calibration of the instrument, the use of the zero gas and standard gas. The standard gas preparation according to GB 5274-5275 actual.
6.2 detection error test
Required by manufacturers of the instrument or device to be corrected. Then the concentration of 60% of full scale value, 1.6 times, three times to allow the test gas concentration or alarm settings pass into the detector, the record indicates that the values and calculate the difference of the indicated value of the test gas concentration.
6.3 alarm error test
6.3.1 Inspection hypoxia detection alarm and oxygen leak detection alarm device, and set the alarm under the same conditions will be higher than the set alarm concentrations of oxygen to pass into the detector, and then gradually reduce the concentration of oxygen, until the alert , calculate the oxygen concentration of the trial and error to set the concentration of oxygen alarm.
6.3.2 In addition to hypoxia detection alarm, inspection and other gas alarm apparatus and gas detection alarm, and set the alarm under the same conditions should be lower than the set alarm concentrations of the measured gas to pass into the detector, and then the concentration of the test gas is gradually increased until an alert occurs, calculate the concentration of the test gas at this time and alarm settings error.
6.4 repeatability test
Approximation under the same conditions, the alarm settings of oxygen test gas and conventional air exchange three times, pass into the detector to calculate the concentration of oxygen test the reproducibility of the oxygen detector and Oxygen Detection 6.4.1, with the concentration of with the indicated mean value of the error.
6.4.2 reproducibility of the combustible gas and toxic gas detectors and detection alarm device, the concentration is about setting the alarm value or 60% of full scale test gases and conventional air or zero gas exchange three times under the same conditions, into the detector, the calculation of the indicated value and its average error of the test gas concentration and the relative average.
6.5 Stability Test
The first correction to the instructions of the alarm detector, set the alarm value, 6.5.1 and 6.5.2 test 6.2 detection error test with 6.3-alarm error test.
6.5.1 the instrument to maintain the working conditions 1h, and then check the detection of error, according to the method specified in 6.2.
6.5.2 enable the instrument to maintain the working conditions of more than 1h, and then, according to the method specified in 6.3 check alarm error.
6.6 Instruments in the posture of the impact test
Equipment in working condition, subject to a standard posture, respectively, 30 ° tilt around, check the value of the test gas concentration indicative concentration values, alarm set concentration value and the actual alarm concentration error.
6.7 vibration test
The instrument is fixed on the shaking table, 10-55Hz frequency, 0.15mm amplitude, each 3min sweep vibration test, each vibration in the vertical and horizontal directions 30min. Then tested by 6.2-6.3 bar
6.8 resistance to impact test
30mm thick pine board placed on the concrete floor, the alarm detector placed above the 0.1m height of the board, in addition to the protection of indication and alarm part, in a working state of the instrument whereabouts. Then, check the test gas concentration value indicative concentration values, alarm setting concentration value and the actual alarm concentration error.
6.9 Detection response time test
Inhaled sampling detection alarm, the tests do not take the catheter.
6.9.1 can be a gas alarm detector, the detector exposed to a concentration of 60% of the full scale of the test gas in mind when measured to reach the instrument indicates 90% of the time of the test gas concentration.
6.9.2 hazardous gas detection alarm, the detector is exposed at a concentration of 60% of full scale test gas at the same time remember when measured to reach the instrument indicates 90% of the time of the test gas concentration.
6.9.3 oxygen detection alarm
a. hypoxia detection alarm, the detector exposed to pure nitrogen or air into the mouth inhalation of nitrogen, and measured the response time to reach 90%;
(b) oxygen leak detection alarm device, the detection part of the exposure to pure nitrogen or air into the mouth inhalation of nitrogen, and measured the response time to reach 90%.
6.10 alarm response time test
6.10.1 can be a gas alarm detector, the detector is exposed to a concentration alarm set value of 1.6 times the test gas in mind when measured alert time.
6.10.2 toxic gas detection alarm, the detector exposure in the concentration of the alarm set value of 1.6 times the test gas, measured at the same time remember, the time of the alert.
6.10.3 oxygen detection alarm
a. hypoxia detection alarm, the alarm concentration setpoint set at 18 (vol.)%, the detector exposed to the test gas of 10 (vol.)%, while the note, measure the time of the alert;
(b) oxygen leak detection alarm device, alarm set value is 25 (vol.)%, the detectors are exposed to concentrations for 28 (vol.)% of test gas at the same time remember when measured by the time of the alert;
6.11 temperature changes affect the test
6.11.1 detect error test and alarm error test in the 20 ± 2 ° C, the calibration of the instrument indicates the concentration value and the value of the alarm concentration. Then the instrument constant temperature bath at 40 ° C, after 1h, the measured value of the test gas concentration at this temperature and instructions concentration, set the alarm concentration value and the actual alarm concentration error. Using the same method of the instrument at 0 ℃ constant temperature bath, after 1h, measured at this temperature the test gas concentration value indicative concentration values, set alarm concentration values and the actual alarm value error.
6.11.2 Detection and Alarm response time test
During the trial 6.11.1 in the same time. Temperature were taken in 35 ° C and 15 ° C, measured the response time test gas detection and alarm response time of change.
6.12 power supply voltage variations affect the test
Correction and detection alarm indication concentration and alarm settings, the main power of predetermined voltage change of ± 10% of test gas concentrations measured value indicative concentration values, alarm settings and alarm value error.
7 detection rules
7.1 The test is divided into inspection and type test.
7.2 factory inspection
7.2.1 factory inspection by one to the 5.2.1,5.2.2 and 5.2.7 and the corresponding test methods according to this standard.
7.2.2 All projects are qualified products in the factory inspection, qualified products, a failure, that is substandard products.
7.3 Type test
7.3.1 There are one of the following situations, the type of inspection should be carried out:
(a) new products or old products to the plant production trial stereotypes identification;
(b) production, such as structures, materials, processes, major changes may affect product performance;
c. normal production, the regular or the accumulation of a certain output, you should periodically conduct an inspection;
(d) the product was halted, to resume production;
(e) the factory test results and the last test are quite different;
(f) national quality oversight bodies of the type of inspection request.
7.3.2 Type tests shall be provided for in this standard case-by-case basis.
7.3.3 Type inspection randomly selected from the qualified products of the factory inspection, a prototype of not less than 3. Test, inspection and project all those who pass its type inspection, a substandard type test is failed.
7.3.4 review criteria
In the type test, if an indicator of failure, the failed double sampling test, if the indicators are still unqualified, the batch type of test failed. Type test failed in eliminating defects and by the second type of inspection before continuing to produce.
8 signs, packaging, transportation and storage
8.1 mark
8.1.1 each alarm detector should be fixed in place nameplate, which shall include:
(a) product name and model;
(b) manufacturing plant name or trademark;
c measurement range;
(d) the number of the manufacturer of the product;
e date of manufacture.
8.1.2 each alarm detector should be in the appropriate parts of the printed instructions for use and precautions (eg, duration, etc.).
8.1.3 The outside of the carton must indicate the following signs:
(a) manufacturer name and address;
(b) the product name and model;
c. number and net weight, gross weight;
(d) box Dimensions;
(e) the packing date.
8.2 Packaging
8.2.1 product packaging should be consistent with the provisions of GB 4857.5, must ensure that the instrument is not in the process of transportation, storage, mechanical damage, and moisture and dust.
8.2.2 box should have the following technical documents:
(a) certificate;
(b) manual;
c products, spare parts and accessories List.
8.3 Transport
Products in transit should be rain, moisture, avoid strong vibration and impact.
8.4 Storage
The product should be stored indoor ventilation, dry, non corrosive gases. Storage temperature is 0-40 ℃, relative humidity below 85%.| Updated:2012.02.07 Source: Clicks:2527
