Datasheet Content
[{"filename":"gao-gml-gmh-a4_datasheet_us_226357.pdf","text":"Pressure Switch\n for gas and air\n\n GAO-A4…\n GMH-A4…\n GML-A4…\n\n\n\n\n UL Listed\n • UL 353\n • File # MH 16628\n\n CSA Certified\n • CSA C22.2 No. 13 and No. 0\n • Certification file # 201527\n\n FM Approved\n • Class 3510, 3530\n • File # J.I. 1Y919.AF\n\n Commonwealth of Massachusetts\n Approved Product\n • Approval code G3-0106-191\n • Gas pressure switch\n\n Codes and Standards\n This product is intended for instal-\n lations covered by but not limited to\n NFPA 85, NFPA 86, UL 795, CSD-1,\n ANSI Z83.4, ANSI Z83.18, ANSI\n Z21.13, CSA B149.1, CSA B149.3\n and CSA B149.6.\n\n DUNGS is an ISO 9001 Description Application\n manufacturing facility. The GAO-, GMH- and GML-A4… vent- The GAO-, GMH-, and GML-A4… pres-\n less pressure switches are adjustable sure switch is recommended for indus-\n pressure switches for automatic burner trial and commercial heating, ventilation\n controls. and air-conditioning systems.\n\n These pressure switches are suitable for The GAO-, GMH-, and GML-A4… pres-\n making and/or breaking a circuit when sure switch is suitable for dry natural\n the medium pressure changes relative gas, propane, butane, air and other\n to the set point. The set point can be set inert gases. Suitable for up to 0.1 % by\n\n\n\n\n GXX_A4 Sales Brochure • P/N 226357 • Ed. 08/23\n in the field by an adjustable dial with an volume, dry H2S.\n integrated scale. Test nipple integrated\n in metal housing to verify set point. A “dry” gas has a dew point lower than\n +15 °F and its relative humidity is less\n than 60 %.\n\n\n\n\n1…6\n\fGAO-A4… SPDT pressure switch requires no auxiliary power. The GAO-A4… is suitable for making and/or breaking a\ncircuit when the set point is exceeded or undershot. A tripped switch is indicated by a neon light after set point is exceeded\nor undershot. Automatic reset when pressure returns below or above set point.\n\nGMH-A4… SPDT pressure switch requires no auxiliary power. The GMH-A4… is suitable for making and/or breaking a\ncircuit when the set point is exceeded. A tripped switch is indicated by a neon light after set point is exceeded.\nManual reset is required to reset the switch.\n\nGML-A4… SPDT pressure switch requires no auxiliary power. The GML-A4… is suitable for making and/or breaking a\ncircuit when the set point is undershot. A tripped switch is indicated by a neon light after set point is undershot.\nManual reset is required to reset the switch.\n\nSpecifications\nMax. operating pressure GAO-A4-4-2,3,5,6 7 PSI (500mbar)\n GMH- and GML-A4-4-4,6 7 PSI (500mbar)\n GAO-, GMH- and GML-A4-4-8 14 PSI (1000 mbar)\nMax. body pressure 15 PSI (1033 mbar)\nPressure connection Standard: 1/4\" NPT female thread centered underside of housing.\nTemperature range:\nGAO-, GMH- and GML-A4-4 Ambient temperature -40 °F to +140 °F (-40 °C to +60 °C)\n Medium temperature -40 °F to +140 °F (-40 °C to +60 °C)\nGAO-, GMH- and GML-A4-4-8 Ambient temperature -22 °F to +140 °F (-30 °C to +60 °C)\n Medium temperature -22 °F to +140 °F (-30 °C to +60 °C)\nMaterials Housing Aluminium\n Switch Polycarbonate\n Diaphragm NBR-based rubber\n Switching contact Silver or Gold\nElectrical ratings AC eff.\t\t min. 24 V max. 240 V\n DC \t\t min. 24 V max. 48 V\nNominal current ratings Silver (Ag) contact ratings Gold (Au) contact ratings\n AC 10 A resistive @ 120 VAC\n AC 8 A pilot duty @ 120 VAC\n DC min. 20 mA @ 24 VDC DC max. 5 mA @ 5 VDC\n DC max. 1 A @ 24 VDC & 48 VDC DC max. 20 mA @ 24 VDC\nIndication light (NEMA 4 vesions) Energy consumption\n 0.1 W max. @ 120 VAC\n 0.5 W max. @ 24 VDC/AC\nElectrical connection Screw terminals via 1/2\" NPT conduit connection\nEnclosure rating NEMA 1 or NEMA 4\nSetting tolerance ±15% switching point deviation referred to set point. Adjusted as pressure rises\n or as pressure falls, vertical diaphragm position.\nVent Limiter Incorporates a vent limiter as per UL 353 and limits the escape of gas less than\n 1.0 CFH of natural gas at 7 PSI if internal switch diaphragm ruptures\n\n\n\n\n 2…6\n\f Dimensions inch (mm)\n GAO-, GMH-, GML-A4…\n\n\n\n\n Integrated 1/8\" test nipple\n 1/4\" NPT pressure connection\n\n\n Reset button\n GMH-A4...\n GML-A4...\n\n\n\n\n NEMA 1\n cover has\n 20 mm\n cutout\n\n\n\n\n NPT 1/2\"\n conduit 4 X Ø 0.16(4,2)\n connection for M4 screws\n\n\n NEMA 1 cover with cutout Ø 20 mm to access reset button\n\n\n GAO (Shown as a high gas limit) GMH (Operating state shown) GML (Operating state shown)\n As pressure rises above set point, As pressure rises, 2 NO closes, As pressure falls, 2 NO opens, 1 NC\n 1 NC opens, 2 NO closes, Neon light 1 NC opens, and Neon light ON (fault), closes, Neon light ON (fault), switch\n ON (fault). As pressure falls below switch trips and locks out. trips and locks out.\n setpoint, switch resets: 1 NC closes\n and 2 NO opens, Neon light off.\n\n\n\n\n O (orange) O (orange) O (orange)\n Medium NE (neon) Medium NE (neon) Medium NE (neon)\n Pressure Pressure Pressure\n\n\n NEMA 1, no light installed NEMA 1, no light installed\n\n\n\n\n3…6\n\fDefinition of switching\nhysteresis ∆p\nThe pressure difference between the Pressure\nupper and lower switching pressures at meter Setpoint tolerance\n Upper switching\n pressure\n\n\n\n\n Switching hysteresis Δp\n Falling\n\n\n Adjustment as\n Rising Lower switching\n pressure rises pressure\n\n\n\n\nInstallation position\n\n\n\n Standard installation position\n\n\n\n\n When installed horizontally, the pressure switch switches at a\n pressure higher by approximately 0.2 in. W.C. (0.5 mbar).\n\n\n\n\n When installed upside down, the pressure switch switches at a\n pressure lower by approximately 0.2 in. W.C. (0.5 mbar).\n\n\n\n\n…
