{"product_id":"siemens-qra4-u-flame-detector","title":"SIEMENS QRA4.U Flame Detector UV Sensor","description":"\u003cstyle\u003e\n.nxs-industrial-product-page {\n--industrial-navy: #082f49;\n    --industrial-blue: #0b4f7c;\n    --industrial-blue-2: #0f6ea8;\n    --industrial-blue-3: #1784c1;\n    --industrial-cyan: #38bdf8;\n    --steel-blue: #dcebf5;\n    --steel-blue-2: #edf6fb;\n    --steel-line: #c9dce9;\n    --surface: #ffffff;\n    --surface-soft: #f7fbfe;\n    --text-main: #173042;\n    --text-muted: #5e7382;\n    --shadow-soft: 0 10px 30px rgba(8, 47, 73, 0.08);\n    --shadow-hover: 0 16px 36px rgba(8, 79, 124, 0.15);\n    --radius-lg: 14px;\n    --radius-md: 10px;\n}\n\n.nxs-industrial-product-page, .nxs-industrial-product-page * {\nmargin: 0;\n    padding: 0;\n    box-sizing: border-box;\n    font-family: Arial, Helvetica, sans-serif;\n}\n\n.nxs-industrial-product-page {\nbackground-color: #f3f8fb;\n    background-image:\n        linear-gradient(180deg, #eef6fb 0, #f7fafc 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0;\n    width: 5px;\n    height: 100%;\n    background: linear-gradient(180deg, var(--industrial-blue-3), var(--industrial-blue));\n}\n\n.nxs-industrial-product-page .section h2 {\nposition: relative;\n    display: inline-flex;\n    align-items: center;\n    gap: 10px;\n    font-size: 25px;\n    line-height: 1.3;\n    color: var(--industrial-navy);\n    margin-bottom: 24px;\n    letter-spacing: -0.2px;\n}\n\n.nxs-industrial-product-page .section h2::before {\ncontent: \"\";\n    width: 28px;\n    height: 4px;\n    flex: 0 0 28px;\n    border-radius: 999px;\n    background: linear-gradient(90deg, var(--industrial-blue-2), var(--industrial-cyan));\n}\n\n.nxs-industrial-product-page .section p {\ncolor: var(--text-main);\n}\n\n.nxs-industrial-product-page .spec-table {\nwidth: 100%;\n    border-collapse: separate;\n    border-spacing: 0;\n    overflow: hidden;\n    border: 1px solid var(--steel-line);\n    border-radius: var(--radius-md);\n    background: #fff;\n}\n\n.nxs-industrial-product-page .spec-table tr {\ntransition: background-color 0.2s ease, transform 0.2s ease;\n}\n\n.nxs-industrial-product-page .spec-table tr:nth-child(even) {\nbackground: #f7fbfe;\n}\n\n.nxs-industrial-product-page .spec-table tr:hover {\nbackground: #eaf5fb;\n}\n\n.nxs-industrial-product-page .spec-table td {\npadding: 13px 16px;\n    border-bottom: 1px solid #dbe7ef;\n    vertical-align: top;\n    color: #294658;\n}\n\n.nxs-industrial-product-page .spec-table tr:last-child td {\nborder-bottom: none;\n}\n\n.nxs-industrial-product-page .spec-table td:first-child {\nposition: relative;\n    width: 38%;\n    font-weight: 700;\n    color: #0b456d;\n    background: rgba(220, 235, 245, 0.42);\n}\n\n.nxs-industrial-product-page .spec-table td:first-child::after {\ncontent: \"\";\n    position: absolute;\n    top: 22%;\n    right: 0;\n    width: 1px;\n    height: 56%;\n    background: #c7dce9;\n}\n\n.nxs-industrial-product-page .features {\ndisplay: grid;\n    grid-template-columns: repeat(auto-fit, minmax(235px, 1fr));\n    gap: 18px;\n}\n\n.nxs-industrial-product-page .card {\nposition: relative;\n    overflow: hidden;\n    min-height: 100%;\n    background: linear-gradient(180deg, #ffffff 0%, #f4f9fc 100%);\n    padding: 22px 20px 21px;\n    border: 1px solid #d5e4ee;\n    border-radius: var(--radius-md);\n    box-shadow: 0 6px 18px rgba(8, 47, 73, 0.055);\n    transition:\n        transform 0.22s ease,\n        box-shadow 0.22s ease,\n        border-color 0.22s ease;\n}\n\n.nxs-industrial-product-page .card::before {\ncontent: \"\";\n    position: absolute;\n    left: 0;\n    top: 0;\n    width: 100%;\n    height: 4px;\n    background: linear-gradient(90deg, var(--industrial-blue), var(--industrial-cyan));\n}\n\n.nxs-industrial-product-page .card::after {\ncontent: \"\";\n    position: absolute;\n    width: 74px;\n    height: 74px;\n    right: -28px;\n    bottom: -30px;\n    border: 1px solid rgba(15, 110, 168, 0.12);\n    border-radius: 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margin: 0;\n    padding: 18px 18px 18px 54px;\n    background: #f8fbfd;\n    border: 1px solid #d8e6ef;\n    border-radius: 9px;\n    box-shadow: 0 4px 12px rgba(8, 47, 73, 0.035);\n    transition: border-color 0.2s ease, background-color 0.2s ease;\n    counter-increment: faq;\n}\n\n.nxs-industrial-product-page .section:last-of-type \u003e p:hover {\nbackground: #f1f8fc;\n    border-color: #bfd8e7;\n}\n\n.nxs-industrial-product-page .section:last-of-type \u003e p::before {\ncontent: counter(faq, decimal-leading-zero);\n    position: absolute;\n    left: 15px;\n    top: 17px;\n    min-width: 28px;\n    height: 28px;\n    display: inline-flex;\n    align-items: center;\n    justify-content: center;\n    border-radius: 6px;\n    background: var(--industrial-blue);\n    color: #fff;\n    font-size: 11px;\n    font-weight: 700;\n    letter-spacing: 0.3px;\n    box-shadow: 0 5px 12px rgba(8, 79, 124, 0.18);\n}\n\n.nxs-industrial-product-page .section:last-of-type \u003e p strong {\ndisplay: inline-block;\n    color: #0b456d;\n    margin-bottom: 5px;\n    line-height: 1.4;\n}\n\n.nxs-industrial-product-page .section:last-of-type \u003e br {\ndisplay: block;\n    content: \"\";\n    margin: 10px 0;\n}\n\n@media (max-width: 760px) {\n.nxs-industrial-product-page .container {\nwidth: 100%;\n        padding: 0 12px 24px;\n}\n\n.nxs-industrial-product-page .section {\npadding: 26px 17px 24px;\n        margin: 14px auto;\n        border-radius: 11px;\n}\n\n.nxs-industrial-product-page .section::before {\nwidth: 4px;\n}\n\n.nxs-industrial-product-page .section h2 {\nfont-size: 21px;\n        margin-bottom: 18px;\n}\n\n.nxs-industrial-product-page .section h2::before {\nwidth: 20px;\n        flex-basis: 20px;\n}\n\n.nxs-industrial-product-page .spec-table {\ndisplay: table;\n        table-layout: fixed;\n}\n\n.nxs-industrial-product-page .spec-table td {\npadding: 11px 9px;\n        font-size: 13px;\n        line-height: 1.55;\n        overflow-wrap: anywhere;\n}\n\n.nxs-industrial-product-page .spec-table td:first-child {\nwidth: 42%;\n}\n\n.nxs-industrial-product-page .features {\ngrid-template-columns: 1fr;\n        gap: 12px;\n}\n\n.nxs-industrial-product-page .card {\npadding: 18px 17px;\n}\n\n.nxs-industrial-product-page .card:hover {\ntransform: none;\n}\n\n.nxs-industrial-product-page .section ul {\ngrid-template-columns: 1fr;\n        gap: 9px;\n}\n\n.nxs-industrial-product-page .section li {\npadding: 11px 12px 11px 36px;\n        font-size: 14px;\n}\n\n.nxs-industrial-product-page .section:last-of-type \u003e p {\npadding: 16px 14px 16px 48px;\n        font-size: 14px;\n}\n\n.nxs-industrial-product-page .section:last-of-type \u003e p::before {\nleft: 12px;\n        top: 15px;\n        min-width: 26px;\n        height: 26px;\n        font-size: 10px;\n}\n}\n\n@media (prefers-reduced-motion: reduce) {\n.nxs-industrial-product-page, .nxs-industrial-product-page *, .nxs-industrial-product-page *::before, .nxs-industrial-product-page *::after {\ntransition: none !important;\n}\n}\n\u003c\/style\u003e\n\n\u003cdiv class=\"nxs-industrial-product-page\"\u003e\u003cdiv class=\"container\"\u003e\u003cmain\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"spec-table\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eSIEMENS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel Number\u003c\/td\u003e\n\u003ctd\u003eQRA4.U\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Category\u003c\/td\u003e\n\u003ctd\u003eFlame Detector UV Sensor\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDetection Technology\u003c\/td\u003e\n\u003ctd\u003eUltraviolet (UV) flame detection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpectral Range\u003c\/td\u003e\n\u003ctd\u003e190 nm to 270 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSensitivity\u003c\/td\u003e\n\u003ctd\u003eNormal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHousing Material\u003c\/td\u003e\n\u003ctd\u003eAluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounting Thread\u003c\/td\u003e\n\u003ctd\u003e3\/4-14 NPSM\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCable Length\u003c\/td\u003e\n\u003ctd\u003eApproximately 1.8 m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePermissible Combustion Chamber Pressure\u003c\/td\u003e\n\u003ctd\u003eMaximum 150 mbar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDegree of Protection\u003c\/td\u003e\n\u003ctd\u003eIP54 (when installed)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temperature\u003c\/td\u003e\n\u003ctd\u003e-20°C to +60°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStorage\/Transport Temperature\u003c\/td\u003e\n\u003ctd\u003e-20°C to +60°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRelative Humidity (Operation)\u003c\/td\u003e\n\u003ctd\u003e\u0026lt;95% r.h.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUV Cell Average Life\u003c\/td\u003e\n\u003ctd\u003e~10,000 hours at max. +50°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight (approx.)\u003c\/td\u003e\n\u003ctd\u003e180 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtection Class\u003c\/td\u003e\n\u003ctd\u003eII (protective insulation)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cdiv class=\"features\"\u003e\n\u003carticle class=\"card\"\u003e\u003ch3\u003eUV Flame Detection\u003c\/h3\u003e\n\u003cp\u003eUses an ultraviolet-sensitive detector cell that responds to radiation in the 190 nm to 270 nm spectral range for flame supervision.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003eGas and Oil Flame Monitoring\u003c\/h3\u003e\n\u003cp\u003eDesigned for monitoring gas flames, yellow\/blue oil flames, and ignition spark supervision in intermittent operation with compatible burner controls.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003eAluminum Housing with NPSM Thread\u003c\/h3\u003e\n\u003cp\u003eThe aluminum housing features a 3\/4-14 NPSM thread for mounting to a burner or boiler, with a connection cable approximately 1.8 m long.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003e150 mbar Combustion Chamber Rating\u003c\/h3\u003e\n\u003cp\u003ePermitted combustion chamber pressure is up to 150 mbar, supporting use in pressurized combustion systems within the specified limit.\u003c\/p\u003e\u003c\/article\u003e\u003carticle class=\"card\"\u003e\u003ch3\u003eIP54 Protection\u003c\/h3\u003e\n\u003cp\u003eThe IP54 degree of protection is ensured by the installation, supporting use in environments where dust and water spray exposure are limited.\u003c\/p\u003e\u003c\/article\u003e\n\u003c\/div\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eApplications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eGas flame supervision in industrial and commercial burner systems\u003c\/li\u003e\n\u003cli\u003eOil flame monitoring for yellow\/blue burning liquid fuels\u003c\/li\u003e\n\u003cli\u003eIgnition spark supervision in intermittent burner operation\u003c\/li\u003e\n\u003cli\u003eCombustion safety systems using compatible Siemens burner controls\u003c\/li\u003e\n\u003cli\u003eBoiler and furnace flame detection applications\u003c\/li\u003e\n\u003cli\u003eBurner management systems requiring UV flame sensing\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003ePurchase Information\u003c\/h2\u003e\n\u003cp\u003eWe support online purchase of the SIEMENS QRA4.U Flame Detector UV Sensor. If you need to make bulk purchases and inquire about other products, please contact our team to inform us of your purchase requirements. We will provide you with information such as quantity quotations, delivery dates, and transportation methods.\u003c\/p\u003e\u003c\/section\u003e\u003csection class=\"section\"\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the SIEMENS QRA4.U?\u003c\/strong\u003e\nThe QRA4.U is a UV flame detector from Siemens designed for flame supervision in gas and oil burner systems with compatible burner controls.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat detection technology does it use?\u003c\/strong\u003e\nIt uses an ultraviolet (UV) detector cell that responds to radiation in the 190 nm to 270 nm spectral range.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat flames can it monitor?\u003c\/strong\u003e\nIt is suitable for monitoring gas flames, yellow\/blue oil flames, and ignition sparks in intermittent operation, depending on the burner control used.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the permissible combustion chamber pressure?\u003c\/strong\u003e\nThe maximum permissible combustion chamber pressure is 150 mbar.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the degree of protection?\u003c\/strong\u003e\nThe QRA4.U has an IP54 degree of protection when installed.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the operating temperature range?\u003c\/strong\u003e\nThe operating temperature range is -20°C to +60°C, with storage and transport tolerance over the same range.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the UV cell life?\u003c\/strong\u003e\nThe average UV cell life is approximately 10,000 hours at a maximum ambient temperature of +50°C; higher temperatures reduce the life.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mounting thread does it have?\u003c\/strong\u003e\nThe aluminum housing has a 3\/4-14 NPSM thread for mounting to a burner or boiler.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the cable length?\u003c\/strong\u003e\nThe electrical connection cable is approximately 1.8 m long.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat should be checked before ordering?\u003c\/strong\u003e\nVerify the QRA4.U model number, the burner control compatibility (such as LFL, LFE, LGB, LME, or LMV series with appropriate UV accessories), the combustion chamber pressure, and the installation location requirements.\u003c\/p\u003e\u003c\/section\u003e\u003c\/main\u003e\u003c\/div\u003e\u003c\/div\u003e","brand":"SIEMENS","offers":[{"title":"Default Title","offer_id":67848700985423,"sku":"LL1-SMS- QRA4.U","price":59.72,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0710\/7569\/2623\/files\/QRA4.U-01_1.jpg?v=1792748346","url":"https:\/\/yunshuotrade.com\/products\/siemens-qra4-u-flame-detector","provider":"yunshuotrade","version":"1.0","type":"link"}