This standard describes the test methods and design requirements for electrical devices used in small boats so that these devices can be used in explosive atmospheres without igniting the surrounding flammable gases. This standard does not apply to explosion-proof or explosive energy-protected electrical appliances as specified in IEC 79-0. This standard does not include measures to prevent ignition of products or components that may be used in hydrogen and air mixtures, nor does it include ignition mechanisms caused by external causes such as static electricity, lightning strikes, or other factors unrelated to the equipment under test. GB/T 17726-1999 Protection of small boat electrical devices against ignition of surrounding flammable gases GB/T17726-1999 Standard download decompression password: www.bzxz.net

1C.S 47. 080
National Standard of the People's Republic of China
GB/T 17726--1999
idt ISO 8846:1990
Electrical devices
Protection against ignition of surrounding fiammable gases
Small craft- Electrical devices-Protection against ignition of surrounding fiammable gasesIssued on April 15, 1999
Implemented on December 1, 1999
Issued by the State Administration of Quality and Technical Supervision
W.GB/17726—1999
This standard is equivalent to ISO 8846:1990&Small craft- Electrical devices-Protection against ignition of surrounding fiammable gases3. Appendix A of this standard is an indicative appendix.
This standard is proposed by China State Shipbuilding Corporation. This standard is under the jurisdiction of the 708th Institute of the 7th Research Institute of China State Shipbuilding Corporation. The drafting units of this standard are: 708th Institute of the 7th Research Institute of China State Shipbuilding Corporation and 601st Institute of China State Shipbuilding Corporation. The drafters of this standard are: He Dehui, Li Zhensheng, Zhang Jisheng, Luo Chunyan. W.bzsosocomGB/T17726—1999
ISO Foreword
The International Organization for Standardization (ISO) is a worldwide federation of national standards bodies (ISO member bodies). The work of formulating international standards is carried out by ISO technical committees. Each member body has the right to participate in the work of a technical committee established by an organization. International organizations, governmental or non-governmental, in liaison with ISO may also participate in this work: ISO International Electrotechnical Commission (IEC) works closely with the International Electrotechnical Commission (IEC) on all subjects of electrotechnical standardization. Draft international standards adopted by the technical committee are circulated to the member bodies for their comments before they are accepted as international standards by the ISO Council. In accordance with the ISO statutes, at least 75% of the member bodies voting in favor shall be considered valid. ISO) 8846 International Standard was prepared by ISO/TC·188 Technical Committee Small Craft. Annex A to this International Standard is for reference only.
W.bzsosocom1 Scope
National Standard of the People's Republic of China
Protection against ignition of surrounding flammable gases by electrical devices in small craft
Small craft--Electrical devices-Protection against ignition of surroundlng fnammable gasesGB/T 17726—1999
JS0 8846:1990
This standard describes the test methods and design requirements for electrical devices used in small craft so that they can be used in explosive atmospheres without igniting the surrounding flammable gases. This standard is not intended for use with appliances of the explosion-proof type or of the type protected against the reverse flow of explosive energy as defined in IEC:790-1.
This standard does not cover measures to prevent ignition of product components that may be used in mixtures of gas and air, nor does it cover ignition mechanisms caused by external sources such as static electricity, shock or other factors unrelated to the equipment under test. 2 Definitions
This standard adopts the following definitions:
2.1 Flammable hydrocarbon mixture flammahlehydrorarbonmixtur A mixture of propane and argon (in percentage by volume) that will explode if ignited in any manner between the lower explosion limit (I, EI.) and the upper explosion limit (UFL). The test using internal combustion and air is considered to include a mixture of marine fuel and air between the LFE and UE1.:
2.2 Ignition-proof device An ignition-proof device that meets the requirements of a test scheme in Chapter 3. 2.3 Ignition source
(1) Any electrical contact, commutator or circuit tree component, or collector ring brush that may produce a voltage with ignition potential. (2) Any resistor or other component or surface that may operate at a voltage sufficient to ignite a flammable mixture. 2.4 Normal operating conditions Any operating condition of the device, including any motor rotor rotation condition in which the circuit is overloaded (breakers, switches and similar devices) up to 400 volts of rated current and protected by overcurrent protection devices specified by the manufacturer. 3 Test program
3.1 The external surface temperature test shall be carried out in accordance with Chapter 4. 3.2 Electrical devices that may produce sparks or voltage during operation (switches, relays, generators, fuses, distributors, starter motors, etc.) shall be tested in accordance with Chapter 5 if they are fully sealed and in accordance with Chapter 6 if they are not sealed. 3.3 Electrical devices whose external surface temperature is more than 100°C higher than the ambient temperature during operation shall be tested in accordance with Chapter 1. Electrical devices whose rating is not for continuous operation and electrical devices connected to instantaneous switches, such as engine starting motors, propulsion equipment, longitudinal regulating motors and other devices operating temporarily, are exempt from this test. Approved by the State Administration of Quality and Technical Supervision on April 15, 1999 and implemented on December 1, 1999
Wbzsoso.cOn 4 External surface temperature test
GB/T 17726-1999
4.1 The electrical device shall be placed in a closed, insulated, air-circulating thermostat with an initial temperature of 60°C + 2°C. In order to keep the temperature in the thermostat at 60°C + 2°C, appropriate heating shall be provided in addition to the heat generated by the tested components. 4.2 The test voltage source should be adjusted within the range of 80% to 120% of the nominal system voltage to maximize the increase in the mixing degree. 4.3 The electrical device should be operated continuously at the maximum current for at least 7 hours. 4.4 The maximum allowable surface temperature measured at any point on the outer surface of the electrical device is 200. - Sealed device
5 Test method - Electrical device that may produce sparks or arcs during operation, if it is considered that it is sealed so that the surrounding "body cannot enter its interior. It should be tested according to 5.1 and 5.2. 5.1 Equipment
A water tank as shown in Figure 1 is required.
5.2 Test procedure
Test assembly chain
Figure 1 Water tank for testing sealed devices
5.2. 1. Immerse the electrical device under test in a water tank at ambient temperature. If necessary, change its posture so that all possible leakage surfaces are on the lower part and immerse it at a depth of 340 to 370 ft below the water surface. For each posture, the immersion time is 15 min. 5.2.2 During the entire test period, carefully observe whether the electrical device under test has leakage. Leakage is indicated by the generation of a bubble or a series of bubbles.
5.2.3 If bubbles are observed escaping from the electrical components of the device, the electrical device shall be considered to be insufficiently sealed and shall be tested in accordance with Chapter 6.
5.2.4 If no bubbles are observed, remove the electrical device from the water tank and wipe its surface. 5.2.5 Disassemble the electrical device for internal inspection; 5.2.6 If no water is found inside the electrical device, it is considered to be a sealed ignition-proof device. If water is found inside the device, it should be tested in accordance with Chapter 6. Test method - unsealed devices
GB/T17726-1999
Electrical devices that may produce dust sparks or arcs during operation and are considered to be open and may be entered by ambient gas should be tested in accordance with 6.[~6.1. Electrical devices that have been found to be unsealed after testing in accordance with Chapter 5 should also be tested in accordance with 6.1~~5.4. 6.1 Equipment
For large sealed electrical devices, a test device as shown in Figure 2 is required. For small unsealed electrical devices, the shell should be covered with a test device as shown in Figure 3. The test chamber shall be equipped with a pressure relief device. 6.2 Preparation of electrical equipment
6.2.1 The flammable mixture of propane and air shall be allowed to enter the electrical equipment through a non-destructive or vaporous pipe with a length of at least 150 mm and an inner diameter of 1.5 to 6.5 mm. The inner diameter selected is the minimum inner diameter that can maintain a test rate of at least 100 ignitions per minute. The gas pipe (see Figure 2) that carries the mixture sample from the equipment to the analyzer shall have an inner diameter of 1.8 mm and a minimum length of 150 m
6.2.2 If the electrical device does not have an opening large enough to allow the mixture to enter at the required rate, a copper vent pipe with a minimum length of 150 mm should be installed on the electrical device, leading from its outlet to the test chamber. The inner diameter of the gas duct shall be the same as the inner diameter of the pipe for conveying the flammable mixture to each electrical device. 6.2.3 If the electrical device is too small to be directly connected to the gas supply pipe to the electrical device and the gas supply pipe for the electrical device and gas analysis, a tee fitting is required to connect the two pipes and then enter the electrical device through a 1.5mm thick insulator or flexible arm at least 150mm long (see Figure 3): 62.4 The spark plug or similar spark plug installed separately from the wall of the electrical device shall have an air gap through which the spark can jump. The size of the gas source shall be large enough to ignite the specified mixture. If possible, it is best to use a 2.5mm gas gap. The spark gap provided should be installed as close as possible to the appropriate part of the electrical device that will produce the arc. At this time, the motor should be in the electrical device. The commutator of the motor shall be equipped with a spark ignition system. 6.2.5 The ignition system of the test chamber shall be a single-shot spark ignition system, which is easily ignited by a mixture of sugar and air. 6.2.6 For confirmation of ignition in the electrical enclosure, the ignition can be detected by the noise produced. If a "bang" sound is clearly heard, measures should be taken to check the voltage increase in the electrical device, or use a gas transmitter with a maximum length of 20 mm and a maximum inner diameter of 6.5 mm (see Figure 3) to observe flashes or combustion for confirmation. This transparent tube should be connected to the electrical device through a hole large enough to transmit the combustion of the device to the transparent tube without extinguishing it. 6.3 Test procedure 6.3.1 Fill the test chamber with a mixture of propane and air in a ratio of 4.75% ± 0.25 (volume ratio V/V). Maintain the gas mixture in the test chamber throughout the test cycle. 6.3.2 The electrical device is charged with a gas mixture in which the ratio of propane to air is determined by varying this ratio to produce the maximum pressure rise (indicated by the sensor). The batch ratio should then be used throughout the test. If, due to the limitations of the available space, a small practical pressure sensor cannot be installed, then a mixture with a ratio of 4.25:0.25 (volume ratio V/V) of propane to air should be used and combustion should be confirmed by the flash of fire seen in the transparent tube (see 3) that conveys the propane-air mixture to the electrical device. The test chamber is a micrometer. 1》Multi-shot single-tooth spark selection. GB/T17726—1999 Reduce the cost of the project
Install the spark plug
Square sensor
Test the installation
Get notification
(if necessary)
The gas in the filling is very difficult
The gas temperature in the filling
The British spark
Set the gas
Analyzer
New gas
New instrument
High pressure Ignition Warring States
Every Sa you 1
Click Yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vasometer
Production interval (H
GB/T 17726—1999
Yuli effect breeding
Circuit breaker
(as)
Adjusting air duct
(if necessary)
Gas in the environment is in accordance with the requirements
Shape★Flower paste
Three-pass attached
Installation industry gas data
Analyzer
1>Multi-shot or single-shot spark optional,
2) If there is space, use a giant force sensor. 6.3.3 After the appropriate mixture has been formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession. 5
W.GB/T 17726 1999
6.3.6 After each tenth ignition of the device, the test mixture shall be ignited with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 only for ten cycles of the test procedure without repeating the entire test. 6.3.7 Repeat steps 6.3.1-6.3.6 four times in succession. If the ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be able to protect against ignition: 6.4 Special instructions for non-sealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be placed in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark gap to 2.5 mm. If necessary, connect the components so that a spark jumps over the air gap and install the high-voltage lead to any remaining terminal connected to the "ground\" pole. Align the contacts of the distributor rotor with the electrodes of this pole. The test of this distributor shall consist of five extended ignition cycles, each of which shall consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres3 If the electrical installation is too small to allow either direct access to the gas line to the electrical installation or to the gas line to the electrical installation and gas analyzer, a tee fitting is required to connect the two pipes and then enter the electrical installation through a flexible or elastic arm at least 150 mm long and 1.5 mm thick (see Figure 3): 62.4 Spark plugs or similar spark plugs installed separately from the wall of the electrical installation shall have an air gap through which the spark can jump. The size of the gas source shall be large enough to allow the front and rear to ignite the specified mixture. If possible, a 2.5 mm gas gap is preferred. The spark gap provided shall be installed as close as possible to the appropriate parts of the electrical installation where the arc will be generated. At the same time, the motor shall be installed with a spark plug at the commutator of the motor. 6.2.5 The test chamber ignition system shall be a single-shot spark system to ensure that the surrounding mixture is easily ignited. 6.2.6 Confirmation of ignition in the electrical enclosure may be checked by the noise produced. If a "clap" sound is clearly heard, the pressure rise in the electrical device shall be checked or confirmed by observing flashes or combustion using a gas transmitter with a maximum length of 20 mm and a maximum inner diameter of 6.5 mm (see Figure 3). This transparent transmitter shall be connected to the electrical device through a hole large enough to transmit the combustion of the device to the transparent tube without extinguishing it. 6.3 Test Procedure
6.3.1 The test chamber shall be filled with a mixture of propane and air in a ratio of 4.75% ± 0.25 (volume ratio V/V). The ratio of the gas mixture in the test chamber shall be maintained throughout the test period. 6.3.2 The electrical device shall be filled with a gas mixture. The ratio of propane to air in the mixture shall be confirmed by varying this ratio to produce the maximum pressure rise (indicated by the sensor). The batch ratio shall then be used throughout the test. If, due to the limited space available, a small practical pressure sensor cannot be installed, then a compound having a burner to air ratio of 4.25:0.25 (volume ratio V/V) should be used and combustion confirmed by the flash of fire seen in the transparent tube (see 3) which feeds the propane-air mixture to the electrical device.
GB/T17726—1999
Power reduction items
Install spark plugs
Side sensor
Test quantity
Get notification
(if necessary)
Gas in the load is very difficult
Gas temperature in the load
British spark
Gas
Analyzer
New gas||tt ||New device
High voltage ignition
Every 1
Click yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vacuum meter
Production interval (H
GB/T 17726—1999
Energy efficiency
Circuit breaker
(as)
Adjustment duct
(if necessary)
Gas in the environment
Shape
Three-pass sample
Installation gas data
Analyzer
1>Multiple strikes or single sparks optional,
2) If there is space, use a giant force sensor. Gas in the box
Analyzer
Single-shot spark
Figure 3 Test device for small non-sealed electrical equipment-high voltage ignition circuit diagram
Vibrator)
Control switch
12V point
6. 3. 3 After the proper mixture is formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession.
W.GB/T 17726 1999
6.3.6 After every ten ignitions of the device, ignite the test mixture with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 for only ten cycles of the test sequence, not the entire test. 6.3.7 Repeat steps 6.3.1 to 6.3.6 four more times in succession. If ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be protected against ignition: 6.4 Special instructions for unsealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark to 2.5 mm. If necessary, connect the components so that a spark jumps across the air gap and install the high voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor should consist of five extended ignition cycles, each of which should consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres3 If the electrical installation is too small to allow either direct access to the gas line to the electrical installation or to the gas line to the electrical installation and gas analyzer, a tee fitting is required to connect the two pipes and then enter the electrical installation through a flexible or elastic arm at least 150 mm long and 1.5 mm thick (see Figure 3): 62.4 Spark plugs or similar spark plugs installed separately from the wall of the electrical installation shall have an air gap through which the spark can jump. The size of the gas source shall be large enough to allow the front and rear to ignite the specified mixture. If possible, a 2.5 mm gas gap is preferred. The spark gap provided shall be installed as close as possible to the appropriate parts of the electrical installation where the arc will be generated. At the same time, the motor shall be installed with a spark plug at the commutator of the motor. 6.2.5 The test chamber ignition system shall be a single-shot spark system to ensure that the surrounding mixture is easily ignited. 6.2.6 Confirmation of ignition in the electrical enclosure may be checked by the noise produced. If a "clap" sound is clearly heard, the pressure rise in the electrical device shall be checked or confirmed by observing flashes or combustion using a gas transmitter with a maximum length of 20 mm and a maximum inner diameter of 6.5 mm (see Figure 3). This transparent transmitter shall be connected to the electrical device through a hole large enough to transmit the combustion of the device to the transparent tube without extinguishing it. 6.3 Test Procedure
6.3.1 The test chamber shall be filled with a mixture of propane and air in a ratio of 4.75% ± 0.25 (volume ratio V/V). The ratio of the gas mixture in the test chamber shall be maintained throughout the test period. 6.3.2 The electrical device shall be filled with a gas mixture. The ratio of propane to air in the mixture shall be confirmed by varying this ratio to produce the maximum pressure rise (indicated by the sensor). The batch ratio shall then be used throughout the test. If, due to the limited space available, a small practical pressure sensor cannot be installed, then a compound having a burner to air ratio of 4.25:0.25 (volume ratio V/V) should be used and combustion confirmed by the flash of fire seen in the transparent tube (see 3) which feeds the propane-air mixture to the electrical device.
GB/T17726—1999
Power reduction items
Install spark plugs
Side sensor
Test quantity
Get notification
(if necessary)
Gas in the load is very difficult
Gas temperature in the load
British spark
Gas
AnalyzerwwW.bzxz.Net
New gas||tt ||New device
High voltage ignition
Every 1
Click yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vacuum meter
Production interval (H
GB/T 17726—1999
Energy efficiency
Circuit breaker
(as)
Adjustment duct
(if necessary)
Gas in the environment
Shape
Three-pass sample
Installation gas data
Analyzer
1>Multiple strikes or single sparks optional,
2) If there is space, use a giant force sensor. Gas in the box
Analyzer
Single-shot spark
Figure 3 Test device for small non-sealed electrical equipment-high voltage ignition circuit diagram
Vibrator)
Control switch
12V point
6. 3. 3 After the proper mixture is formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession.
W.GB/T 17726 1999
6.3.6 After every ten ignitions of the device, ignite the test mixture with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 for only ten cycles of the test sequence, not the entire test. 6.3.7 Repeat steps 6.3.1 to 6.3.6 four more times in succession. If ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be protected against ignition: 6.4 Special instructions for unsealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark to 2.5 mm. If necessary, connect the components so that a spark jumps across the air gap and install the high voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor should consist of five extended ignition cycles, each of which should consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres6. Confirmation of ignition in the electrical enclosure may be checked by the noise produced. If a "clap" sound is clearly heard, the pressure rise in the electrical device shall be checked or confirmed by observing flashes or combustion using a gas supply tube with a maximum length of 20 mm and a maximum internal diameter of 6.5 mm (see Figure 3). This transparent tube shall be connected to the electrical device through a hole large enough to transmit the combustion of the device to the transparent tube without extinguishing it. 6.3 Test procedure
6.3.1 The test chamber shall be filled with a mixture of propane and air in a ratio of 4.75% ± 0.25 (volume ratio V/V). The ratio of the gas mixture in the test chamber shall be maintained throughout the test period. 6.3.2 The electrical device is filled with a gas mixture. The ratio of propane to air in the mixture is confirmed by varying this ratio to produce the maximum pressure rise (indicated by the sensor). The batch ratio shall then be used throughout the test. If, due to the limited space available, a small practical pressure sensor cannot be installed, then a compound having a burner to air ratio of 4.25:0.25 (volume ratio V/V) should be used and combustion confirmed by the flash of fire seen in the transparent tube (see 3) which feeds the propane-air mixture to the electrical device.
GB/T17726—1999
Power reduction items
Install spark plugs
Side sensor
Test quantity
Get notification
(if necessary)
Gas in the load is very difficult
Gas temperature in the load
British spark
Gas
Analyzer
New gas||tt ||New device
High voltage ignition
Every 1
Click yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vacuum meter
Production interval (H
GB/T 17726—1999
Energy efficiency
Circuit breaker
(as)
Adjustment duct
(if necessary)
Gas in the environment
Shape
Three-pass sample
Installation gas data
Analyzer
1>Multiple strikes or single sparks optional,
2) If there is space, use a giant force sensor. Gas in the box
Analyzer
Single-shot spark
Figure 3 Test device for small non-sealed electrical equipment-high voltage ignition circuit diagram
Vibrator)
Control switch
12V point
6. 3. 3 After the proper mixture is formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession.
W.GB/T 17726 1999
6.3.6 After every ten ignitions of the device, ignite the test mixture with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 for only ten cycles of the test sequence, not the entire test. 6.3.7 Repeat steps 6.3.1 to 6.3.6 four more times in succession. If ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be protected against ignition: 6.4 Special instructions for unsealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark to 2.5 mm. If necessary, connect the components so that a spark jumps across the air gap and install the high voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor should consist of five extended ignition cycles, each of which should consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres6. Confirmation of ignition in the electrical enclosure may be checked by the noise produced. If a "clap" sound is clearly heard, the pressure rise in the electrical device shall be checked or confirmed by observing flashes or combustion using a gas supply tube with a maximum length of 20 mm and a maximum internal diameter of 6.5 mm (see Figure 3). This transparent tube shall be connected to the electrical device through a hole large enough to transmit the combustion of the device to the transparent tube without extinguishing it. 6.3 Test procedure
6.3.1 The test chamber shall be filled with a mixture of propane and air in a ratio of 4.75% ± 0.25 (volume ratio V/V). The ratio of the gas mixture in the test chamber shall be maintained throughout the test period. 6.3.2 The electrical device is filled with a gas mixture. The ratio of propane to air in the mixture is confirmed by varying this ratio to produce the maximum pressure rise (indicated by the sensor). The batch ratio shall then be used throughout the test. If, due to the limited space available, a small practical pressure sensor cannot be installed, then a compound having a burner to air ratio of 4.25:0.25 (volume ratio V/V) should be used and combustion confirmed by the flash of fire seen in the transparent tube (see 3) which feeds the propane-air mixture to the electrical device.
GB/T17726—1999
Power reduction items
Install spark plugs
Side sensor
Test quantity
Get notification
(if necessary)
Gas in the load is very difficult
Gas temperature in the load
British spark
Gas
Analyzer
New gas||tt ||New device
High voltage ignition
Every 1
Click yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vacuum meter
Production interval (H
GB/T 17726—1999
Energy efficiency
Circuit breaker
(as)
Adjustment duct
(if necessary)
Gas in the environment
Shape
Three-pass sample
Installation gas data
Analyzer
1>Multiple strikes or single sparks optional,
2) If there is space, use a giant force sensor. Gas in the box
Analyzer
Single-shot spark
Figure 3 Test device for small non-sealed electrical equipment-high voltage ignition circuit diagram
Vibrator)
Control switch
12V point
6. 3. 3 After the proper mixture is formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession.
W.GB/T 17726 1999
6.3.6 After every ten ignitions of the device, ignite the test mixture with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 for only ten cycles of the test sequence, not the entire test. 6.3.7 Repeat steps 6.3.1 to 6.3.6 four more times in succession. If ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be protected against ignition: 6.4 Special instructions for unsealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark to 2.5 mm. If necessary, connect the components so that a spark jumps across the air gap and install the high voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor should consist of five extended ignition cycles, each of which should consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres25 (volume ratio V/V) of the compound, and confirmed by the flash of fire seen in the transparent tube (see 3) that conveys the propane-air mixture to the electrical device,
:com test
Blue Zhishang
Combination chamber
Micrometer
Method of measuring palm section Lang.
1》Multi-shot single-tooth spark selection.
GB/T17726—1999
Power reduction items
Install spark plugs
Side sensor
Test quantity
Get notification
(if necessary)
Gas in the load is very difficult
Gas temperature in the load
British spark
Gas
Analyzer
New gas||tt ||New device
High voltage ignition
Every 1
Click yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vacuum meter
Production interval (H
GB/T 17726—1999
Energy efficiency
Circuit breaker
(as)
Adjustment duct
(if necessary)
Gas in the environment
Shape
Three-pass sample
Installation gas data
Analyzer
1>Multiple strikes or single sparks optional,
2) If there is space, use a giant force sensor. Gas in the box
Analyzer
Single-shot spark
Figure 3 Test device for small non-sealed electrical equipment-high voltage ignition circuit diagram
Vibrator)
Control switch
12V point
6. 3. 3 After the proper mixture is formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession.
W.GB/T 17726 1999
6.3.6 After every ten ignitions of the device, ignite the test mixture with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 for only ten cycles of the test sequence, not the entire test. 6.3.7 Repeat steps 6.3.1 to 6.3.6 four more times in succession. If ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be protected against ignition: 6.4 Special instructions for unsealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark to 2.5 mm. If necessary, connect the components so that a spark jumps across the air gap and install the high voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor should consist of five extended ignition cycles, each of which should consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres25 (volume ratio V/V) of the compound, and confirmed by the flash of fire seen in the transparent tube (see 3) that conveys the propane-air mixture to the electrical device,
:com test
Blue Zhishang
Combination chamber
Micrometer
Method of measuring palm section Lang.
1》Multi-shot single-tooth spark selection.
GB/T17726—1999
Power reduction items
Install spark plugs
Side sensor
Test quantity
Get notification
(if necessary)
Gas in the load is very difficult
Gas temperature in the load
British spark
Gas
Analyzer
New gas||tt ||New device
High voltage ignition
Every 1
Click yes
[Control switch
Figure 2 Test device for large non-sealed electrical devices W. Test box
Transparent tube
Balloon in the box
Temperature compound
Prohibited Yang (
Limited combination
Vacuum meter
Production interval (H
GB/T 17726—1999
Energy efficiency
Circuit breaker
(as)
Adjustment duct
(if necessary)
Gas in the environment
Shape
Three-pass sample
Installation gas data
Analyzer
1>Multiple strikes or single sparks optional,
2) If there is space, use a giant force sensor. Gas in the box
Analyzer
Single-shot spark
Figure 3 Test device for small non-sealed electrical equipment-high voltage ignition circuit diagram
Vibrator)
Control switch
12V point
6. 3. 3 After the proper mixture is formed, stop charging and ignite the mixture in the device with a spark. If any attempt to ignite the mixture in the device fails, return to 6.5.1, purge the gas from the device and the test chamber, and repeat only steps 6.3.1 to 6.3.4 without repeating the entire test.
6.3.4 Confirm combustion in the electrical device
6.3.5 Repeat steps 6.3.1 to 6.3.4 nine times in succession.
W.GB/T 17726 1999
6.3.6 After every ten ignitions of the device, ignite the test mixture with a single spark to confirm that the mixture is highly flammable. If any attempt to ignite the mixture in the test chamber fails, sweep the electrical device and the test chamber and repeat steps 6.3.1 to 6.3.4 for only ten cycles of the test sequence, not the entire test. 6.3.7 Repeat steps 6.3.1 to 6.3.6 four more times in succession. If ignition of the electrical device (step 6.3.3) does not result in ignition in the test chamber, the electrical device shall be considered to be protected against ignition: 6.4 Special instructions for unsealed electrical devices 6.4.1 Starting motor
When testing the starting motor, the transmission pinion shall be in the position it will occupy when the motor is energized. If the motor can be energized with the transmission pinion either retracted or extended, the starting motor shall be tested with the transmission pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark to 2.5 mm. If necessary, connect the components so that a spark jumps across the air gap and install the high voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor should consist of five extended ignition cycles, each of which should consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheresThe drive pinion shall be placed in the position it will occupy when the motor is energized. If the motor can be energized with the drive pinion either retracted or extended, the starter motor shall be tested with the drive pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark gap to 2.5 mm. Connect the components as necessary so that a spark jumps across the air gap and install the high-voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor shall consist of five extended ignition cycles, each of which shall consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheresThe drive pinion shall be placed in the position it will occupy when the motor is energized. If the motor can be energized with the drive pinion either retracted or extended, the starter motor shall be tested with the drive pinion in both positions.
6.4.2 Distributor
Modify the contacts of the distributor rotor and increase the spark gap to 2.5 mm. Connect the components as necessary so that a spark jumps across the air gap and install the high-voltage lead to any remaining terminal connected to the "ground" terminal. Align the contacts of the distributor rotor with the electrodes of this column. The test of this distributor shall consist of five extended ignition cycles, each of which shall consist of sparking for 5 minutes after the distributor mixture is ignited according to 6.3.1-~E.3.3. If the mixture in the test chamber is ignited, the distributor shall be considered unqualified. 6.4.3 Intrinsically safe devices
Electrical devices that produce low-energy sparks during normal operation as described in IFC79-11=\ can be considered as intrinsically safe devices. The definition of an intrinsically safe device is: under the most severe operating conditions, the current flowing through the device is at a very low level so that the device cannot release any thermal energy that may ignite the gas mixture in any way, as specified in 6.1.3.1. 6.4.3.1 Such devices are generally not exempt from being tested according to this standard. This is because the magnitude of the current through any device is related to the impedance of the common neutral components and the power supply voltage. In addition, changes in inductance, current and voltage, coupled with multiple devices and parallel operation, may change the energy flowing through the device. 6.4. 3.2 If it is known that the parameters used no longer change and the maximum energy state has been strictly recognized and limited, then the actual test of this device may not be carried out. If the absolute maximum energy released on the spark element in the device is not greater than 0.24mJ, the device can be accepted for use in explosive atmospheres.
7 Marking
7.1 A marking consisting of "GB/T17726idtIS()8846" and the words "MARINE" ("use") shall be provided in any appropriate manner to indicate that the device complies with this standard. 7.2 The marking shall be as durable as practicable. 6
WW.bzsoso.cOm Free download of various US standard industry materials GB/T 17726 --1999
(Reminder Appendix)
References
[1]IEC 79-0;1983, Electrical appliances for explosive gas atmospheres Part 0: General requirements
Part 11: Structure and tests of intrinsically safe and related electrical appliances: [2]IFC79-11:1984, Electrical appliances for explosive gas atmospheres
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