{"product_id":"bosch-d281a-dual-chamber-ionization-smoke-detector","title":"Bosch D281A Dual-Chamber Ionization Smoke Detector","description":"\u003ch4 class=\"PDq2pG_selectionAnchorContainer\"\u003eDescription\u003cspan class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\n\u003c\/h4\u003e\n\u003cp class=\"PDq2pG_selectionAnchorContainer\"\u003eThe Bosch D281A is an ionization smoke detector designed to identify smoke particles in commercial fire alarm applications. Its dual-chamber sensing design compares ionization current levels to determine alarm conditions while tolerating humidity, temperature variation, vibration, and electromagnetic interference. It is suitable for locations including plenum areas and raised compartments beneath floors.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCondition\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNew\/Never Used Surplus\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eBosch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCategory\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eFire Alarm Systems\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eD281A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSubcategory\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eIonization Smoke Detectors\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eProduct Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eIonization Smoke Detector\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDetection Technology\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDual-Chamber Ionization\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eNominal Voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e24 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eWorking Voltage (Two-Wire)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e15 to 33 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRated Voltage (Four-Wire)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e17.7 to 30 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eStandby Current\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.04 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSurge Current\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.2 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMaximum Alarm Current\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.15 A at 24 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOperating Temperature\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e+32°F to +120°F (0°C to +49°C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRelative Humidity\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e95% maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDetector Head Diameter\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e4 in. (10.2 cm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDetector Height\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.5 in. (3.8 cm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eColor\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eWhite\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCompatible Bases\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eD250A, D280A, D290, D291M, D291S\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eWeight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch4\u003eInformation About \u003cspan\u003eD281A\u003c\/span\u003e\n\u003c\/h4\u003e\n\u003cp class=\"PDq2pG_selectionAnchorContainer\"\u003e\u003cmeta charset=\"utf-8\"\u003eThe D281A is a Bosch ionization smoke detector built around a removable, non-polarized 24 VDC detector head and dual-chamber sensing architecture. It is compatible with selected low-profile, tamper-resistant two-wire and four-wire detector bases, including Bosch D250A, D280A, and D290 models. The sensing assembly uses a sealed inner chamber as a controlled reference while the screened outer chamber responds to changes in airborne smoke particles. Integrated green and red LED indicators provide visual identification of powered and alarm states, while a moisture-resistant reed switch enables magnetic functional testing.\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eKey Features:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eDual-Chamber Detection: Uses inner reference and outer sensing chambers to monitor changes caused by smoke particles.\u003cspan class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e24 VDC Detector Head: Features a removable, non-polarized head for straightforward installation and servicing.\u003c\/li\u003e\n\u003cli\u003eFlexible Base Compatibility: Supports selected Bosch two-wire, four-wire, and addressable detector bases.\u003c\/li\u003e\n\u003cli\u003eWide Working Voltage: Operates from 15 to 33 VDC when configured for compatible two-wire applications.\u003c\/li\u003e\n\u003cli\u003eStatus Indicators: Flashing green LED indicates applied power, while steady red identifies an alarm condition.\u003c\/li\u003e\n\u003cli\u003eMagnetic Testing: Moisture-resistant reed switch permits detector testing with an applied magnet.\u003c\/li\u003e\n\u003cli\u003eEnvironmental Tolerance: Designed to function under conditions involving humidity, vibration, temperature variation, and electromagnetic interference.\u003c\/li\u003e\n\u003cli\u003eScreened Sensing Chamber: Outer chamber screening helps filter dust and deter insects while permitting smoke entry. \u003cspan class=\"contents\"\u003e\u003cspan class=\"\"\u003e\u003c\/span\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe D281A delivers the reliability and precision required for smoke detection within compatible commercial fire alarm systems.\u003c\/p\u003e","brand":"Bosch","offers":[{"title":"Default Title","offer_id":52212268073258,"sku":"D281A","price":297.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/0392\/4266\/files\/s-l1600_d14d94c1-e1c8-4aa8-b6d8-81fab1a21197.webp?v=1786395002","url":"https:\/\/iqelectro.com\/products\/bosch-d281a-dual-chamber-ionization-smoke-detector","provider":"IQElectro","version":"1.0","type":"link"}