{"product_id":"castair-10-hp-230-volt-1-phase-magnetic-starter-s101-with-overload","title":"Castair 10 HP 230 Volt. 1 Phase* Magnetic Starter S101 With Overload","description":"\u003cp\u003eThe \u003cstrong\u003eCastair S101\u003c\/strong\u003e is the OEM magnetic motor starter for \u003cstrong\u003e10 HP, 230-Volt, single-phase Castair piston air compressors\u003c\/strong\u003e. This is a fully assembled magnetic starter with overload relay, factory-configured for the S101 application. The associated overload heater element is the \u003cstrong\u003eB70\u003c\/strong\u003e, which is required for proper overload protection at this motor rating — one heater is used with this single-phase starter. Castair specifies name-brand, off-the-shelf magnetic starters and controls on all their compressors specifically so shops can source replacements without going through proprietary channels.\u003c\/p\u003e\n\n\u003ch2\u003eWhat a Magnetic Starter Does — and Why It Matters\u003c\/h2\u003e\n\u003cp\u003eA magnetic motor starter combines three functions that are all critical for compressor motor protection:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor starting:\u003c\/strong\u003e The contactor closes to apply power to the motor. On a single-phase 10 HP motor at 230V, starting current is significantly higher than running current — the starter is rated to handle that inrush without contact damage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverload protection:\u003c\/strong\u003e The overload relay (with B70 heater element) monitors motor current. If the motor draws excessive current — from a locked rotor, low voltage, bearing failure, or seized pump — the overload trips and disconnects power before the motor winding insulation burns. This is the primary motor protection mechanism.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemote control integration:\u003c\/strong\u003e The magnetic coil allows pressure switch control — the pressure switch turns the starter on and off, not the motor directly. This protects the pressure switch contacts (which are rated for low-current coil loads, not motor loads) and provides a safe, controlled start-stop sequence.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eHeater Element Specification\u003c\/h2\u003e\n\u003cp\u003eThe S101 requires one \u003cstrong\u003eB70 heater element\u003c\/strong\u003e for single-phase overload protection. The heater element must be matched to the actual running current of your specific motor — B70 is the Castair-specified heater for the standard 10 HP 230V single-phase application. If your motor's nameplate FLA differs from the standard specification, verify the heater element sizing against the overload relay's selection chart.\u003c\/p\u003e\n\n\u003ch2\u003eCastair Magnetic Starter Lineup — Single-Phase Models\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eS51\u003c\/strong\u003e — 5 HP, 208\/230V, 1-phase, heater: B36\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eS71\u003c\/strong\u003e — 7.5 HP, 208\/230V, 1-phase, heater: B45\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eS101 (this unit)\u003c\/strong\u003e — 10 HP, 230V, 1-phase, heater: B70\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFor three-phase 10 HP applications, see S102 (208\/230V 3-phase) or S104 (460V 3-phase). Single-phase 10 HP motors draw significantly more current than their 3-phase equivalents at the same horsepower — the S101 is heavier-duty than the S102 despite the same nameplate HP.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eOne B70 heater element required (single-phase — one heater per phase)\u003c\/li\u003e\n\u003cli\u003eVerify supply voltage matches 230V rating before installation\u003c\/li\u003e\n\u003cli\u003eCastair compressors ship with starter mounted and wired from the factory — this replacement starter mounts in the same enclosure and connects to the same terminals\u003c\/li\u003e\n\u003cli\u003eVerify pressure switch wiring reconnects to the magnetic coil terminals, not the load terminals\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e S101\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor Horsepower:\u003c\/strong\u003e 10 HP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVoltage:\u003c\/strong\u003e 230 Volt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhase:\u003c\/strong\u003e 1-Phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverload:\u003c\/strong\u003e Included\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRequired Heater Element:\u003c\/strong\u003e B70 (1 required for 1-phase)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Cast Air\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy Buy From OEM Diagnostic Tools?\u003c\/h3\u003e\n\u003cp\u003eOEM Castair magnetic starters — correct contactor rating and overload relay for the S101 application. Free shipping on qualifying orders. Free tech support at \u003cstrong\u003e866-217-0063\u003c\/strong\u003e. Full Castair manufacturer warranty. Call us if you need the B70 heater element as well — we can supply the complete assembly.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342598332629,"sku":"S101","price":995.42,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0622\/8466\/0949\/files\/MAGNETIC-MOTOR-STARTERS_ce25efc8-8352-42e4-a58c-acf41042e8d6.jpg?v=1772652891","url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-10-hp-230-volt-1-phase-magnetic-starter-s101-with-overload","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}