DustExplosion-proof positive pressure cabinetIsOneVariousProfessionalUsersInCombustible DustEnvironmentNext的Explosion-proof positive pressure cabinet，explosion-proofidentificationForpD，explosion-proofStandardGB12476ForDustTypeExplosion-proof positive pressure cabinet的structure、protectionrequirements、safetydeviceEtc.Withdetailed的Regulations，DustExplosion-proof positive pressure cabinetinMetallurgy、Coal Mine、thermal power plant、LargeChemical Plant、PharmaceuticalWorkshopEtc.locationwidelyShouldUsers。

　　One、DustExplosion-proof positive pressure cabinetGeneral Requirements

　　inEnsureStableExplosion-proof positive pressure cabinetInternalDescribeCostPositive PressurePositionFront，ShouldUseEnhancedProtective MeasuresavoidanceInstallationinEnclosureInelectricalequipmentVentilationElectric。LocationsWithsafetydeviceShouldadoptNextColumnThreeVariousProtective MeasuresPositionOne:

　　a) UserscompliantCombustible DustEnvironmentUsersElectricalequipment的SomeOneVariousExplosion-proof TypeProtection;

　　b) IsnonElectrical的 And InvincibleAbilityTriggerRisePointGas;

　　c) StatusInnonHazardous Location。

　　Explosion-proof positive pressure cabinetShouldinsystempower supply的power supplyWeldingVentilationPositionFrontAdvanced BlowingSweep，ManufacturerShouldTowardUserprovideMustCritical的详AsBlowingSweepEnclosurerequirements的Manual。

The manufacturer should specify the maximum and minimum actuation values and tolerances of the safety devices.。Considering the worst conditions specified for normal operation, the safety devices should be used within the normal operating range as specified by the manufacturer.。

　　(1)DustExplosion-proof positive pressure cabinetResponsedevice

　　ForAlarm And Electricaldetach扣deviceoperation And setup的pressureResponsedeviceShouldinEnclosureDomesticpressureLowInPermitMostSmallValue Or exceedPermitMostGreaterpressureWhenInteractionOperating。

Flow monitoring devices provided for the operation of alarms and electrical tripping devices should actuate when the pressure inside the enclosure falls below the allowable minimum value or exceeds the allowable maximum value, and the flow monitoring device should be located at the outlet.。

Electrical interlocks on fan motors or controllers are not suitable for indicating positive pressure faults. When fan belt slippage occurs, the fan becomes loose on the shaft, or the fan reverses, the electrical interlock will not indicate a positive pressure fault.。

　　(2)DustExplosion-proof positive pressure cabinetpower supply

　　 If 没WithprovidePositive PressureProtectionsystemshutdown Or faultPositionAfter-salesavoidanceDustEntry的Protection，thenShouldsetupAlarm告Brand，StandardBrightinWeldingVentilationpower supplyPositionFrontClearRemoveInternalDust。

　　(3)CutPower OffSource

　　 If requirementsCutPower OffSource，Shouldaccording toGB 12476.2 的Regulations，ShouldrequirementsCutDeterminationLocationsWithEnergizedWire，includingInPerformanceLine。

　　(4)Positive Pressurefault

　　Positive PressureProtectionsystem的DesignPrinciplebased onPositive PressurefaultautomaticDeterminationOpensystempower supply And ( Or )StartAlarm。

　　ForavoidancePositive PressureProtectionelectricalequipmentinProtectionGasPower SupplyShouldInDetermination的situationNext May TriggerRiseexplosion，ShouldUseEnhancedNextColumnMeasures:

　　2、DustExplosion-proof positive pressure cabinetProtectionrequirements

　　according toLocationsUsersequipment的type、location的classificationWith And WithStructureInstallation And processrequirements的InvincibleSame，UpWithrequirementsUseEnhancedOnlyAlarm Or PioneerDeterminationOpenpower supply And Alarm的Measures。 But non论UseEnhancedWhatProtective Measures，alsoShouldUseEnhancedNextColumnMeasures:

　　a)LocationsWith的innonPositive Pressure的situationNextVentilationElectricelectricalequipmentShouldsuitable forLocationsProcessingposition的Explosive DustEnvironment。

b) Visual or audible alarm devices should be provided so that responsible personnel can take necessary action immediately upon directly seeing or hearing the alarm signal.。

c) Pressure monitoring devices, flow monitoring devices, or both should be used to monitor whether the positive pressure function meets the requirements.。

　　(1)Overvoltagelevel

　　RelatedforExternalAtmospheric Pressure，in May generateLeakDrain的Positive PressureEnclosure And ItsPipelineDomestic的VariousPoint的pressureShouldProtectionSupport50 Pa 的MostLowOvervoltage。

　　(2)PotentialinPointGasSource

　　QuitebeProtection的equipmentDomesticInstallationwithPointGasSource的ComponentsWhen，inDesignequipmentWhenShouldUseEnhancedSuitableQuite的Measures，guaranteeThesesomeComponentsDesignCostwithWithSuitableOverallInExternal And Internal EnvironmentSpecial征的explosion-proofTypeForm，Withavoidancespark偶howevergenerate。

　　Three、DustExplosion-proof positive pressure cabinetstructure

　　(1)DomesticInstallationComponents

　　EnclosureDomesticin没WithProtectionGas的situationNextContinueoperation的anywhatComponents，Such asinTomorrowoperationRegularAreaheatingequipment的device，ShouldUserscompliantCombustible DustEnvironmentUsersElectricalequipment的explosion-proofTypeFormPositionOnePlusWithProtection，Withsuitable forWithStructureHazardous Location。

　　(2)IndependentlyRemainEnclosure

　　 If equipmentIsUsersComeconstituteMoreProductionEnclosuredevice的OnePart，TogetherUsersSameOneProductionProtectionAir Source，DesignWhenShouldConsiderEntireProductiondevice的MostInvincibleProfitcondition。

　　 If TogetherUsersProtection Device，inNextColumnsituationNextPunchingOpenSiemens Or CoverWhen，InvincibleMustCutDeterminationSafeExternalpower supply Or StartAlarm:

　　a)PunchingOpenSiemens Or CoverPositionAfter-salesnonProtective Measures的equipment，inPunchingOpenSiemens Or CoverPositionFront，ShouldDeterminationOpenpower supply， Or WillSiemens And power supplyLinkedLock;

　　b)TogetherUsersProtection DeviceContinueUsersInMonitoringOtherequipment。

The positive pressure enclosure should be filled with inert gas in a non-hazardous area using the method specified by the manufacturer.。Automatic safety devices should be provided to operate when the overpressure inside the positive pressure enclosure drops below the minimum value specified by the manufacturer.。When the equipment is in operation, it should be possible to check whether these safety devices operate correctly.。These automatic devices should only be reset using tools or a key.。The minimum overpressure value should be greater than the maximum pressure loss measured over one cycle during normal operation, with this cycle being not less than 100 times the time required for internal components to cool below the maximum allowable surface temperature of the dust concerned. Double，Customer FirstLessFor1 h。Under the most severe conditions specified for normal operation, the minimum overpressure value should be at least 50 Pa higher than the external pressure. 。

　　4、DustExplosion-proof positive pressure cabinetAir Sourcerequirements

　　(1)ProtectionGasShouldUsersInProtectionSupportDustExplosion-proof positive pressure cabinet的Positive Pressurestatestate。The protective gas should not, by its own chemical characteristics or due to impurities it may contain, reduce the protection level below the specified level, or seriously affect the normal operation and integrity of the explosion-proof positive pressure cabinet.。When necessary, methods should be provided to remove any oil, moisture, or other impurities from the protective gas that do not meet requirements.。The manufacturer should specify the protective gas and other gases permitted for use.。

(2) Secondary gas supply source. If a secondary protective gas supply is required in the event of failure of the primary protective gas supply, each gas source should be capable of independently maintaining the specified pressure level or flow rate of the protective gas.。

(3) Temperature. At the inlet of the enclosure, the temperature of the protective gas should normally not exceed 40 °C. 。Under special circumstances, higher or lower temperatures are permitted.。In such cases, this should be marked on the dust explosion-proof positive pressure cabinet.。