Electrical appara tus It refers to the whole or part of all equipment that uses electric energy, such as power generation, power transmission, power distribution, electricity storage, electricity measurement, regulation, conversion, power equipment and telecommunications engineering equipment.
Explosive environment potentia lly explosive a tmosphere A potentially explosive environment.
Explosive gas environment explosive ga sa tmosphere Under atmospheric conditions, a mixture of gas, vapor, or mist-like flammable substances and air. When the mixture is ignited, the combustion will spread throughout the environment of the unburned mixture.
Explosive dust a tmosphere Under atmospheric conditions, dust or fibrous combustible materials form a mixture with air. After being ignited, the combustion is transmitted to the environment of all unburned mixtures.
Explosive mixture A flammable gas, vapor, mist, dust, or fiber-air mixture between the upper and lower explosive limits.
Lower explosive lower limit (LEL) The concentration of flammable gas, vapor or mist in the air, below which no explosive gas environment can be formed.
Upper explosive lim it (UEL) The concentration of flammable gases, vapors or mists in the air above which no explosive gas environment can be formed.
Maximum test safety gap max imum exper imenta l safe gap (MESG) Under the specified test conditions, the test device can prevent the flame from igniting the external gas mixture through the 25 mm long joint between the two parts of the internal chamber after the test gas or vapor and air mixture of various concentrations in the internal chamber is ignited. The maximum clearance of the joint surface.
Explosion (of an explosive a tmosphere) A sudden increase in pressure and temperature caused by oxidation or other exothermic reactions.
Flash point fla sh po int The minimum temperature of a liquid that causes a liquid to release a certain amount of vapor under certain standard conditions to form an ignitable vapor-air mixture.
Explosive testm ixture Specific explosive mixtures used in explosion-proof electrical equipment tests.
Working temperature serv ice tempera ture The temperature reached by the device during rated operation.
Maximum working temperature max imum serv ice tempera ture Maximum operating temperature. Note: Different parts of each device may have different maximum operating temperatures.
Max imum surface tempera ture When electrical equipment is operated under the most permissive adverse conditions, the highest temperature on its surface or any part may reach and possibly ignite the surrounding explosive gas environment.
Ignition temperature of an explosive ga sa tmosphere When tested in accordance with the method specified in IEC 6007924, the lowest temperature of the hot surface capable of igniting an explosive gas-air mixture.
Temperature group (of electrical equipment for explosive environments) temperature cla ss (of an electr ica l appara tus forexplosive a tmospheres) Groups of electrical equipment for explosive environments by their highest surface temperature.
Type of protection Specific measures to prevent electrical equipment from igniting the surrounding explosive gas environment.
Explosion-proof electrical equipment explosion2protected electr ica l appara tus Electrical equipment that does not cause the surrounding explosive environment to ignite under specified conditions.
(Group of an electr ica l appara tus for explosive a tmospheres) The classification according to the explosive environment in which electrical equipment is used. GB3836 divides explosion-proof electrical equipment into two categories: Category Ⅰ includes electrical equipment for underground coal mines; Category Ⅱ includes all electrical equipment for explosive gas environments except underground coal mines. This type of equipment is divided into several levels.
Enclosure In order to realize the explosion-proof type or degree of protection (IP) of electrical equipment, all the walls, doors, covers, cable entries, rods, shafts, spindles, etc. are integrated.
Degree of protection prov ided by enclosures (of electr ica l appara tus) The protection level of the enclosure of electrical equipment is determined according to the following protective measures: a) Preventing humans from touching or approaching live parts and moving parts (except smooth rotating shafts and similar parts) inside the enclosure, preventing solid foreign matter from entering the interior of the electrical equipment; b) Preventing water Enter and damage equipment inside the enclosure.
Hazardous area Areas where explosive gas atmospheres appear or are expected to occur are sufficient to require special measures for the structure, installation and use of electrical equipment.
Non2hazardous area Areas where explosive gas environments are not expected to occur in large numbers so that special precautions are not required for the structure, installation and use of electrical equipment.
Dust dust Solid particles (including dust and particles as defined in ISO4225) that can be precipitated in the atmosphere by their own weight, but can also be suspended in the air for a period of time.
Combustible dust Dust that may burn or smolder when mixed with air and form explosive mixtures with air at normal temperature and pressure.
Ra ting Usually refers to a quantity specified by the manufacturer for the specific operating conditions of the component, equipment or device.
Normal work norma l opera tion It refers to the working state that meets the design requirements of intrinsically safe electrical equipment or related equipment in both electrical and mechanical aspects.
Fault Refers to any failure of any component that is not defined as reliable and will affect the intrinsic safety performance of the circuit, including failure of the separation, insulation or connection between components.
Countable fault Faults on electrical instrument parts that meet the requirements of standard structures.
Non-countable failure Faults on electrical instrument parts that do not meet the standard structure requirements.
Conductive dust Resistivity is 1 x 103 Ω or less
m of dust, fibers or flying objects.
Explosive dust a tmosphere Under atmospheric environmental conditions, after the mixture of dust or fibrous combustible material and air is ignited, the combustion is transmitted to the environment of all unburned mixtures.
Dust ignition protection (D IP) National standard GB 12476.1 applies to all measures on electrical equipment to avoid ignition of dust layers or dust clouds (such as preventing dust from entering and limiting surface temperature). Note: The GB 12476.1 standard includes two different types of electrical equipment, type A and type B. Both types have the same level of protection.
Dust-tight enclosure Enclosure that prevents all visible dust particles from entering.
Dust2 protected enclosure It is not possible to completely prevent dust from entering, but the amount of entry will not prevent the enclosure from operating safely. Dust should not accumulate in the enclosure where there is a danger of ignition.
Minimum ignition temperature of dust layer in imum ign ition tempera ture of a dust layer Minimum temperature of a hot surface where a dust layer of a specified thickness will ignite on a hot surface.
Minimum ignition temperature of dust cloud m in imum ign ition tempera ture of a dust cloud The minimum temperature of the inner wall of the furnace when the dust cloud contained in the air in the furnace ignites.
Flameproof enclosure An explosion-proof type of electrical equipment. Its casing can withstand the flammable mixture that penetrates into the interior of the casing through any joint surface or structural gap without damaging it internally, and does not cause the ignition of an explosive environment formed by one or more gases or vapors.
Volume The total internal volume of the enclosure. If the outer shell and the internal parts cannot be separated in use, the volume refers to the net volume.
Flameproof joint face flameproof jo int The corresponding surfaces of different parts of the flameproof enclosure are fitted together (or the joint of the enclosure), and the flame or combustion products may be transmitted from the interior of the enclosure to the location outside the enclosure.
Flame path length (joint surface width) length of flame pa th (width of jo int) The shortest path length from the inside of the flameproof enclosure through the joint surface to the outside of the flameproof enclosure.
Gap (diametral clearance) The distance between the corresponding surfaces of the flameproof joint. For a cylindrical surface, the gap is a diameter gap (the difference between the two diameters).
Pressure piling Ignition of an explosive gas mixture in a cavity or a space in the shell causes the pre-pressed explosive gas mixture in the other cavity communicated with it to ignite.
Simple device simple appara tus The defined electrical parameters are fully compatible with the intrinsically safe performance of the circuit used, or a combination of simple components. Simple equipment usually refers to electrical equipment or components whose voltage does not exceed 115 V and current does not exceed 011 A, and whose energy does not exceed 20 μJ or power does not exceed 25 mW.
Type test Tests performed on one or more electrical devices manufactured in accordance with a design to determine whether the design complies with the relevant standards.
Routine test Tests performed on each piece of electrical equipment during manufacture or after manufacture is completed to determine whether it meets the requirements of relevant standards.
Ex component It cannot be used alone and has the symbol "U". When used with other electrical equipment or systems, additional parts or assemblies of electrical equipment for explosive gas atmospheres (except for Ex cable entry devices) are required.
Symbol "X" "X" symbol A symbol added to the explosion-proof certificate number to indicate certain conditions for its safe use.
Symbol "U" "U" symbol A symbol added to the explosion-proof certificate number to indicate that the product is an Ex component. Note: The symbols "X" and "U" cannot be used at the same time.
Certif ica te Documents used to determine that the equipment complies with the requirements of the standard, type testing and routine testing for adaptation. The certificate can be for Ex equipment or Ex components.
Maximum external inductance to resistance ratio (L0 / R0) max imum externa l inductance to resistance ra tio The ratio of inductance to resistance of an external circuit that can be connected to an electrical equipment connection without compromising intrinsically safe performance.
Maximum input voltage (Ui) max imum input voltage The highest voltage (AC peak or DC) applied to the connection of an intrinsically safe circuit without ineffective intrinsic safety performance.
Maximum input current (Ii) max imum input current Maximum current (AC peak or DC) applied to the connection of an intrinsically safe circuit without ineffective intrinsic safety performance.
Maximum input power (Pi) max imum input power The maximum input power of an intrinsically safe circuit that may be consumed inside the electrical equipment when the electrical equipment is connected to an external power source without rendering it intrinsically safe.
Maximum internal capacitance (Ci) max imum interna l capac itance The total equivalent internal capacitance of the electrical equipment that appears through the electrical equipment connection.
Maximum internal inductance (L i) max imum interna l inductance Total Equivalent Internal Inductance of Electrical Equipment Appearing Through Electrical Equipment Connections.
Maximum internal inductance to resistance ratio (L i / Ri) max imum interna l inductance to resistance ra tio The ratio of inductance to resistance that appears on the external connections of electrical equipment.
Maximum voltage (AC effective value or DC Um) max imum rmsac or dc voltage The highest voltage applied to the non-intrinsically safe connection of associated equipment without ineffective intrinsic safety performance.
Mystone 's explosion-proof products are SC910N and SC910 combustible gas detectors. Different gases can be used for gas detection by replacing sensors.