{"product_id":"1pcs-new-for-r934000449-12v-solenoid-valve-coil-replacement","title":"1Pcs R934000449 12V Solenoid Valve Coil Replacement","description":"\u003cdiv class=\"koeed-container\" style=\"width: 100%; box-sizing: border-box; padding: 0; margin: 0; color: #333333; line-height: 1.6;\"\u003e\n\n  \u003c!-- SECTION 1: Engineer's Quick Brief --\u003e\n  \u003ch2\u003eEngineer's Quick Brief\u003c\/h2\u003e\n  \u003cul style=\"list-style-type: disc; padding-left: 20px; margin-bottom: 24px;\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eDirect Bosch Rexroth OEM Fit:\u003c\/strong\u003e Guaranteed factory specification replacement tracking for Rexroth material number \u003cstrong\u003eR934000449\u003c\/strong\u003e, restoring precise cartridge valve actuation matrices.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e100% ED Continuous Duty:\u003c\/strong\u003e Engineered with a premium high-density copper winding configuration capable of sustaining non-stop operational cycles without induction degradation.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eClass H Thermal Defense:\u003c\/strong\u003e Outfitted with advanced 180°C Class H insulation matrices to survive aggressive fluid power environments, preventing localized winding shorts and structural failure under backpressure spikes.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003c!-- SECTION 2: SEO Introduction --\u003e\n  \u003ch2\u003eBosch Rexroth R934000449 Solenoid Valve Coil Overview\u003c\/h2\u003e\n  \u003cp style=\"margin-bottom: 24px;\"\u003e\n    The \u003cstrong\u003eBosch Rexroth R934000449\u003c\/strong\u003e is a premium replacement \u003cstrong\u003e12V DC solenoid valve coil\u003c\/strong\u003e engineered explicitly for industrial and mobile hydraulic control systems. This inductive power component acts as the primary mechanical actuator for a diverse range of Rexroth directional control cartridge valves and proportional logic blocks. Operating on a low-voltage \u003cstrong\u003e12V DC\u003c\/strong\u003e framework, the R934000449 generates a robust electromagnetic field required to stroke internal valve spools smoothly against intense spring rates and high-pressure fluid dynamics. Built to industrial heavy-duty criteria, this coil provides long-term operational consistency across precision automated machinery setups and processing plants.\n  \u003c\/p\u003e\n\n  \u003c!-- SECTION 3: Technical Specifications --\u003e\n  \u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n  \u003cdiv style=\"overflow-x: auto; margin-bottom: 24px;\"\u003e\n    \u003ctable style=\"width: 100%; border-collapse: collapse; border: 1px solid #eeeeee; min-width: 600px;\"\u003e\n      \u003cthead\u003e\n        \u003ctr style=\"background-color: #16c8c8; color: #ffffff;\"\u003e\n          \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eSpecification Parameter Category\u003c\/th\u003e\n          \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eDetailed Engineering Factory Values\u003c\/th\u003e\n        \u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eBrand \/ Original Manufacturer\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eBosch Rexroth\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #fafafa;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eFactory Material Number\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eR934000449\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eRated Input Voltage\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003e12V DC (Direct Current)\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #fafafa;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eDuty Cycle Threshold\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003e100% ED (Continuous Duty Capability)\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eInsulation Class Profile\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eClass H (Rated up to 180°C Maximum Winding Temperature)\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #fafafa;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eVoltage Tolerance Envelope\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003e±10% of Nominal Supply Limits\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eMagnetic Core Compatibility\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eDesigned for BoschRexroth Cartridge Valves Assembly Blocks\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #fafafa;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eOperational Medium\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eMineral-Based Hydraulic Fluids and Synthetic Esters Support\u003c\/td\u003e\n        \u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\n  \u003c!-- SECTION 4: Application Matrix --\u003e\n  \u003ch2\u003eIndustrial Application Matrix\u003c\/h2\u003e\n  \u003cdiv style=\"overflow-x: auto; margin-bottom: 24px;\"\u003e\n    \u003ctable style=\"width: 100%; border-collapse: collapse; border: 1px solid #eeeeee; min-width: 600px;\"\u003e\n      \u003cthead\u003e\n        \u003ctr style=\"background-color: #0056B3; color: #ffffff;\"\u003e\n          \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eTarget Deployment Domain\u003c\/th\u003e\n          \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eSpecific Hydraulic Mechanism\u003c\/th\u003e\n          \u003cth style=\"padding: 12px; text-align: left; border: 1px solid #eeeeee;\"\u003eSystem Engineering Value Realized\u003c\/th\u003e\n        \u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eMobile Machinery \u0026amp; Agriculture\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eBoom Lift and Steering Cartridge Blocks\u003c\/td\u003e\n          \u003ctd\u003eSustains constant force profiles despite intense physical chassis vibration and changing vehicle power outputs.\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #fafafa;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003eIndustrial Processing Plants\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eDirectional Spool Control Manifolds\u003c\/td\u003e\n          \u003ctd\u003eDelivers crisp millisecond-level valve shifting cycles to enable predictable automation flow synchronization.\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr style=\"background-color: #f4fcfc;\"\u003e\n          \u003ctd\u003e\u003cstrong\u003ePlastic Injection Molding\u003c\/strong\u003e\u003c\/td\u003e\n          \u003ctd\u003eClamping Force Hydraulic Circuits\u003c\/td\u003e\n          \u003ctd\u003eThe Class H matrix withstands high continuous thermal spikes near heated machinery zones without insulation degradation.\u003c\/td\u003e\n        \u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\n  \u003c!-- SECTION 5: Koeed B2B Tool --\u003e\n  \u003ch2\u003eKoeed Field FAE Tool: Solenoid Coil Thermal Drift \u0026amp; Current Simulator\u003c\/h2\u003e\n  \u003cp style=\"margin-bottom: 16px;\"\u003eAs a hydraulic coil heats up during continuous operation, the internal copper resistance increases naturally. This thermal drift causes a corresponding drop in electrical current and magnetic force. Use this simulator to evaluate the coil's operational status under various temperature profiles.\u003c\/p\u003e\n  \n  \u003cdiv class=\"koeed-tool-box\" style=\"background-color: #fafafa; border: 1px solid #16c8c8; border-radius: 4px; padding: 20px; margin-bottom: 24px;\"\u003e\n    \u003cdiv style=\"display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 20px;\"\u003e\n      \u003cdiv\u003e\n        \u003clabel style=\"display: block; font-weight: bold; margin-bottom: 6px;\"\u003eNominal Input Voltage (V DC):\u003c\/label\u003e\n        \u003cinput type=\"number\" id=\"koeed-coil-v\" value=\"12\" min=\"9\" max=\"15\" step=\"0.1\" style=\"width: 100%; padding: 8px; border: 1px solid #cccccc; border-radius: 4px; box-sizing: border-box;\" oninput=\"koeedCalculateCoilDrift()\"\u003e\n      \u003c\/div\u003e\n      \u003cdiv\u003e\n        \u003clabel style=\"display: block; font-weight: bold; margin-bottom: 6px;\"\u003eCold Base Resistance at 20°C (Ω):\u003c\/label\u003e\n        \u003cinput type=\"number\" id=\"koeed-coil-r-cold\" value=\"7.2\" min=\"3.0\" max=\"30.0\" step=\"0.1\" style=\"width: 100%; padding: 8px; border: 1px solid #cccccc; border-radius: 4px; box-sizing: border-box;\" oninput=\"koeedCalculateCoilDrift()\"\u003e\n      \u003c\/div\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"margin-bottom: 20px;\"\u003e\n      \u003clabel style=\"display: block; font-weight: bold; margin-bottom: 6px;\"\u003eSimulated Internal Operating Temp: \u003cspan id=\"koeed-temp-val\" style=\"color: #16c8c8;\"\u003e85\u003c\/span\u003e°C\u003c\/label\u003e\n      \u003cinput type=\"range\" id=\"koeed-temp-range\" min=\"20\" max=\"180\" value=\"85\" style=\"width: 100%; accent-color: #16c8c8;\" oninput=\"document.getElementById('koeed-temp-val').innerText = this.value; koeedCalculateCoilDrift();\"\u003e\n    \u003c\/div\u003e\n\n    \u003cdiv style=\"background-color: #ffffff; border-left: 4px solid #16c8c8; padding: 14px; border-radius: 0 4px 4px 0;\"\u003e\n      \u003cp style=\"margin: 0; font-weight: bold;\"\u003eCalculated Thermal Resistance: \u003cspan id=\"koeed-calc-r-hot\" style=\"color: #333;\"\u003e9.04\u003c\/span\u003e Ω\u003c\/p\u003e\n      \u003cp style=\"margin: 4px 0 0 0; font-weight: bold; font-size: 1.1em;\"\u003eEstimated Current Draw: \u003cstrong id=\"koeed-calc-coil-amps\" style=\"color: #16c8c8;\"\u003e1.33\u003c\/strong\u003e A\u003c\/p\u003e\n      \u003cp style=\"margin: 4px 0 0 0; font-weight: bold;\"\u003eResulting Power Consumption: \u003cspan id=\"koeed-calc-coil-watts\" style=\"color: #0056B3;\"\u003e15.93\u003c\/span\u003e W\u003c\/p\u003e\n      \u003cdiv style=\"margin-top: 10px; padding-top: 10px; border-top: 1px dashed #eeeeee; font-size: 0.95em; color: #555555;\"\u003e\n        \u003cspan\u003e\u003cstrong\u003eRelative Magnetic Force Efficiency:\u003c\/strong\u003e \u003cspan id=\"koeed-calc-force-pct\" style=\"font-weight: bold; color: green;\"\u003e80.0%\u003c\/span\u003e\u003c\/span\u003e\n      \u003c\/div\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cnoscript\u003e\n    \u003cdiv style=\"background-color: #fff3cd; color: #856404; padding: 12px; border: 1px solid #ffeeba; border-radius: 4px; margin-bottom: 24px;\"\u003e\n      \u003cstrong\u003eNotice:\u003c\/strong\u003e This landing layout includes an active inductive thermal coefficient simulator. Please enable browser JavaScript support to utilize real-time impedance calculation maps.\n    \u003c\/div\u003e\n  \u003c\/noscript\u003e\n\n  \u003cscript\u003e\n    function koeedCalculateCoilDrift() {\n      var volts = parseFloat(document.getElementById('koeed-coil-v').value) || 12.0;\n      var rCold = parseFloat(document.getElementById('koeed-coil-r-cold').value) || 7.2;\n      var tHot = parseFloat(document.getElementById('koeed-temp-range').value) || 20;\n\n      \/\/ Temperature coefficient of copper = 0.00393 per degree C\n      var rHot = rCold * (1.0 + 0.00393 * (tHot - 20.0));\n      var amps = volts \/ rHot;\n      var watts = volts * amps;\n\n      var baseAmps = volts \/ rCold;\n      var forcePct = (amps \/ baseAmps) * 100;\n\n      document.getElementById('koeed-calc-r-hot').innerText = rHot.toFixed(2);\n      document.getElementById('koeed-calc-coil-amps').innerText = amps.toFixed(2);\n      document.getElementById('koeed-calc-coil-watts').innerText = watts.toFixed(2);\n      \n      var forceSpan = document.getElementById('koeed-calc-force-pct');\n      forceSpan.innerText = forcePct.toFixed(1) + \"%\";\n      \n      if (forcePct \u003e= 75) {\n        forceSpan.style.color = \"green\";\n      } else if (forcePct \u003e= 60 \u0026\u0026 forcePct \u003c 75) {\n        forceSpan.style.color = \"#ffc107\";\n      } else {\n        forceSpan.style.color = \"#dc3545\";\n      }\n    }\n    window.addEventListener('DOMContentLoaded', function() {\n      koeedCalculateCoilDrift();\n    });\n  \u003c\/script\u003e\n\n  \u003c!-- SECTION 6: Troubleshooting \u0026 FAQ --\u003e\n  \u003ch2\u003eField Maintenance \u0026amp; Troubleshooting Guide\u003c\/h2\u003e\n  \n  \u003ch3\u003eQ: How can a technician accurately verify if the R934000449 coil is electrically defective?\u003c\/h3\u003e\n  \u003cp style=\"margin-bottom: 12px;\"\u003e\n    To determine whether a malfunctioning valve is caused by a faulty solenoid coil, follow this testing routine using a digital multimeter set to resistance mode (Ω):\n  \u003c\/p\u003e\n  \u003col style=\"padding-left: 20px; margin-bottom: 16px;\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eIsolate Power Systems:\u003c\/strong\u003e Disconnect the electrical terminal block plug from the coil to isolate the winding completely from external circuitry.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMeasure Main Pin Resistance:\u003c\/strong\u003e Connect the multimeter leads across the two active power pins on the coil connector interface. An **Infinity \/ Open Circuit (OL)** reading points to an internal wire break. A reading **close to 0 Ω** indicates an internal short circuit across the copper layers.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eCheck for Ground Faults:\u003c\/strong\u003e Measure resistance from each individual power terminal pin to the external metallic structural frame of the coil. This reading must register as completely open (**OL**). Any measurable low resistance confirms an insulation failure, causing current to leak to the machine ground plane.\u003c\/li\u003e\n  \u003c\/ol\u003e\n\n  \u003ch3\u003eQ: The solenoid coil burns out repeatedly within a brief operational timeframe. What is the root cause?\u003c\/h3\u003e\n  \u003cp style=\"margin-bottom: 12px;\"\u003ePremature coil burnout typically stems from circuit anomalies or physical operational constraints rather than structural wire defects. Check these field variables:\u003c\/p\u003e\n  \u003col style=\"padding-left: 20px; margin-bottom: 16px;\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMechanical Valve Core Jamming:\u003c\/strong\u003e If the matching internal hydraulic valve spool is stuck due to fluid contamination or particulate matter, the coil cannot slide over the armature core completely. This mechanical obstruction prevents the completion of the magnetic loop path, causing intense induction overcurrent draw that quickly overheats and burns out the insulation layer.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eExcessive Voltage Swings:\u003c\/strong\u003e Check your power bus parameters using an oscilloscope during load switching cycles. Continuous operating voltages exceeding 13.2V DC will over-saturate the copper windings, generating severe thermal energy.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eAir Gaps in Physical Seating:\u003c\/strong\u003e Operating a solenoid coil while it is unmounted from its physical armature tube assembly will cause rapid overheating and failure within minutes due to the lack of an inductive core path.\u003c\/li\u003e\n  \u003c\/ol\u003e\n\n  \u003ch3\u003eQ: Can this 12V DC coil handle AC voltage spikes?\u003c\/h3\u003e\n  \u003cp style=\"margin-bottom: 12px;\"\u003e\n    No. The R934000449 is structured purely for low-voltage, continuous **DC power grids**. Introducing AC ripple voltage or connecting it directly to alternative AC lines will cause severe structural chatter, heating, and immediate burnout of the insulation system.\n  \u003c\/p\u003e\n\n  \u003c!-- SECTION 7: Cross-Reference \u0026 Selection --\u003e\n  \u003ch3\u003eCross-Reference Guide\u003c\/h3\u003e\n  \u003cp style=\"margin-bottom: 16px;\"\u003eThe Bosch Rexroth R934000449 10-digit material code matches or operates interchangeably as a structural alternative for these fluid power configurations:\u003c\/p\u003e\n  \u003cul style=\"list-style-type: square; padding-left: 20px; margin-bottom: 24px;\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eRexroth Legacy Reference Tracking:\u003c\/strong\u003e Replaces older generation 12V DC cartridge valve coil architectures that match the same armature tube core diameter specifications.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eUniversal Hydraulic Cross-Matching:\u003c\/strong\u003e Functions as a suitable functional replacement for standard 12V DC industrial fluid power manifolds requiring equivalent structural seating width and magnetic force variables (verify connector interfaces before installation).\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n\u003c\/div\u003e\n\n\u003c!-- STRUCTURED DATA: JSON-LD FOR AI SEARCH ENGINE HARVESTING --\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"FAQPage\",\n      \"mainEntity\": [\n        {\n          \"@type\": \"Question\",\n          \"name\": \"How can a technician accurately verify if the R934000449 coil is electrically defective?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"Technicians can verify structural continuity by reading resistance across the active terminal interface pins. An infinity reading indicates an open loop, while zero resistance points to an internal short circuit. Additionally, check for insulation breakdown by ensuring an open path exists between any pin and the external metal frame body.\"\n          }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"The solenoid coil burns out repeatedly within a brief operational timeframe. What is the root cause?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"Repeated burnout usually points to mechanical jamming of the valve spool due to particulate contamination, preventing correct armature positioning and causing continuous overcurrent. Other common causes include chronic overvoltage spikes above 13.2V DC or running the coil while unmounted from its core tube assembly.\"\n          }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Can this 12V DC coil handle AC voltage spikes?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"No. The R934000449 coil is designed strictly for clean DC power supplies. Applying alternating current or experiencing high AC ripple profiles will cause erratic armature chattering, severe localized heat generation, and immediate structural burnout.\"\n          }\n        }\n      ]\n    },\n    {\n      \"@type\": \"WebApplication\",\n      \"name\": \"Solenoid Coil Thermal Drift \u0026 Current Simulator\",\n      \"applicationCategory\": \"BusinessApplication\",\n      \"operatingSystem\": \"All\",\n      \"browserRequirements\": \"Requires a modern HTML5 compliant web browser configuration with active JavaScript code processing blocks enabled.\",\n      \"description\": \"An interactive technical field assistant built to model copper resistance shifts and evaluate active current and power performance for 12V industrial solenoid configurations under fluctuating thermal loads.\"\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"KOEED","offers":[{"title":"Default Title","offer_id":43858069258425,"sku":"305125559611","price":213.44,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0268\/8476\/7929\/files\/1Pcs_New_For_R934000449_12V_solenoid_valve_coil_Replacement___KOEED__1.webp?v=1779653126","url":"https:\/\/koeed.com\/hi\/products\/1pcs-new-for-r934000449-12v-solenoid-valve-coil-replacement","provider":"KOEED","version":"1.0","type":"link"}