{"product_id":"castair-7hp-3-phase-industrial-air-compressor-horizontal-tank-w-mounted-starter-i733hc1-s","title":"Castair 7HP 3-Phase Industrial Air Compressor  Horizontal Tank w\/ Mounted Starter - I733HC1-S","description":"\u003cp\u003eThe Castair I733HC1-S is a 7.5 HP, 3-phase industrial air compressor built on a 30-gallon horizontal ASME tank with a factory-mounted magnetic motor starter. This is the smallest horizontal tank configuration in Castair's 7.5HP 3-phase industrial lineup — designed for shops that need genuine industrial-grade cast iron performance in a tighter footprint or where floor space constraints make the 80-gallon horizontal impractical. If you're running a 3-phase service drop and want a ready-to-wire unit with overload protection already mounted, the -S suffix tells you the magnetic starter is included at the factory.\u003c\/p\u003e\n\n\u003cp\u003eThis compressor uses the Castair C1 pump — a two-stage cast iron unit running at 895 RPM. At that speed, the pump turns slowly enough that heat stays manageable, wear is minimal, and you can expect a long service life without major overhauls. The C1 pump uses an inline-2 cylinder configuration and is rated at 32.4 CFM at 0 PSI, delivering 24.8 CFM at 175 PSI working pressure. For a shop running air ratchets, impact wrenches, blow guns, and tire equipment simultaneously, that's a solid supply figure.\u003c\/p\u003e\n\n\u003ch2\u003eWhy 3-Phase Matters for Shop Compressors\u003c\/h2\u003e\n\u003cp\u003eIf your building has 3-phase power, running a single-phase compressor is leaving efficiency and longevity on the table. Three-phase motors start smoother, run cooler, draw lower peak current, and last longer than equivalent single-phase motors under continuous shop use. The I733HC1-S is wired for 3-phase from the factory — the magnetic motor starter handles the overload protection and gives you a proper disconnect point. No single-phase conversion required, no add-on starter to source separately.\u003c\/p\u003e\n\n\u003ch3\u003ePump Features — Cast Iron C1 Two-Stage\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll cast iron construction:\u003c\/strong\u003e Cylinders, heads, and crankcase are cast iron throughout — no aluminum hot spots, no warped pump heads under sustained load\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSlow 895 RPM operation:\u003c\/strong\u003e The C1 pump runs at 895 RPM with this motor combination, compared to 1,725 RPM on a typical direct-drive compressor. Slower speed means lower heat, less wear, and a much longer pump life\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTapered roller bearings at both crankshaft ends:\u003c\/strong\u003e Handles radial and thrust loads better than ball bearings, especially under the belt-drive side load\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision steel connecting rods:\u003c\/strong\u003e Automotive-type rod insert bearings at crankshaft, needle bearings at wrist pin — not stamped sheet metal hardware\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDisc and spring valves:\u003c\/strong\u003e Easy to service, more efficient than reed valves, and more reliable under sustained pressure cycling\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-ring pistons:\u003c\/strong\u003e Better ring seal means less oil carry-over into the discharge air and cleaner air to your tools\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCentrifugal unloader:\u003c\/strong\u003e Every start is a no-load start — the unloader releases head pressure before the motor torques up, protecting both motor and pump on every cycle\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTank and Frame Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e30-gallon horizontal ASME-rated tank:\u003c\/strong\u003e Powder coated, channel-supported horizontal configuration for stable floor mounting\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eASME safety valve:\u003c\/strong\u003e Factory installed, rated for the working pressure of the system\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMetal belt guard:\u003c\/strong\u003e Fully enclosed, not a plastic clip-on — meets OSHA guarding requirements\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCopper discharge and unloader tube:\u003c\/strong\u003e Copper handles heat dissipation better than rubber or plastic alternatives and won't crack from oil or pressure cycling\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eMotor and Electrical\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e1,725 RPM heavy-duty industrial motor:\u003c\/strong\u003e Full 15% service factor or higher — built to run at rated load continuously without overheating\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFactory-mounted magnetic motor starter:\u003c\/strong\u003e 3-phase overload protection installed at the factory, wired and ready — eliminates the need to source and mount a separate starter\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e3-phase operation:\u003c\/strong\u003e Lower starting current, smoother operation, and better motor longevity compared to single-phase in a shop environment\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eCastair I733HC1-S compressor assembly (pump, motor, tank, belt drive, belt guard)\u003c\/li\u003e\n\u003cli\u003eFactory-mounted magnetic motor starter (3-phase, sized for 7.5HP)\u003c\/li\u003e\n\u003cli\u003eASME safety valve (installed)\u003c\/li\u003e\n\u003cli\u003eCopper discharge and unloader tube (installed)\u003c\/li\u003e\n\u003cli\u003ePressure switch (installed)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAvailable Configurations — 7.5HP 3-Phase Industrial Lineup\u003c\/h2\u003e\n\u003cp\u003eCastair builds the 7.5HP 3-phase lineup in several tank configurations. Understanding where the I733HC1-S sits helps you pick the right one:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eI733HC1-S (this unit):\u003c\/strong\u003e 7.5HP, 3-phase, 30-gal horizontal, C1 pump, 895 RPM, 32.4 CFM@0PSI \/ 24.8 CFM@175PSI — smallest horizontal tank in this HP class, with magnetic starter\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI738HC1-S:\u003c\/strong\u003e Same HP and pump, 80-gallon horizontal tank — more reserve volume for tools with higher burst demand, dimensions 64x20x48 in., 625 lbs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI738HC2-S:\u003c\/strong\u003e 7.5HP, 3-phase, 80-gal horizontal, C2 pump (585 RPM), 35.0 CFM@0PSI \/ 28.1 CFM@175PSI — higher CFM output with the larger C2 pump\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI738VC1-S:\u003c\/strong\u003e 7.5HP, 3-phase, 80-gal vertical, C1 pump — same output as HC1, vertical tank for smaller floor footprint, dimensions 32x24x74 in., 625 lbs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI7312HC2-S:\u003c\/strong\u003e 7.5HP, 3-phase, 120-gal horizontal, C2 pump — maximum reserve for high-demand shops\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen Does a Shop Need This vs. Stepping Up or Down\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eThe I733HC1-S is right for you if:\u003c\/strong\u003e You have 3-phase power, want an industrial-grade compressor in a compact horizontal package (secondary compressor, limited floor space situation), and need the magnetic starter already mounted so you can connect power and start working. The 30-gallon tank with 24.8 CFM at 175 PSI supports multiple hand tools running simultaneously in a moderate-demand shop.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStep up to the I738HC1-S\u003c\/strong\u003e if you have the floor space and want more air reserve — the 80-gallon tank means longer intervals between compressor cycles, which matters for sustained operations like spray painting or sandblasting.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStep up to the HC2 variants\u003c\/strong\u003e (C2 pump) if you need higher CFM. The C2 pump at 585 RPM delivers 28.1 CFM at 175 PSI vs. 24.8 CFM from the C1 — meaningful when running high-demand tools or multiple bays simultaneously.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStep down to a commercial\/garage series\u003c\/strong\u003e if you don't have 3-phase power or the industrial pump construction is more than your duty cycle requires.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e I733HC1-S\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHorsepower:\u003c\/strong\u003e 7.5 HP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhase:\u003c\/strong\u003e 3-phase\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Capacity:\u003c\/strong\u003e 30 gallons\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTank Type:\u003c\/strong\u003e Horizontal, ASME-rated, powder coated\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Model:\u003c\/strong\u003e C1 (two-stage, cast iron)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump RPM:\u003c\/strong\u003e 895\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 0 PSI:\u003c\/strong\u003e 32.4\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM @ 175 PSI:\u003c\/strong\u003e 24.8\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Working Pressure:\u003c\/strong\u003e 175 PSI\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMotor Speed:\u003c\/strong\u003e 1,725 RPM\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Stage:\u003c\/strong\u003e Two-stage\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePump Cylinder Configuration:\u003c\/strong\u003e Inline 2\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStarter:\u003c\/strong\u003e Factory-mounted magnetic motor starter included\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDischarge Tube:\u003c\/strong\u003e Copper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Guard:\u003c\/strong\u003e Metal, fully enclosed\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h3\u003e\n\u003cp\u003eWe specialize in industrial and commercial air compressors. When you call us, you're talking to someone who knows the difference between a C1 and C2 pump, can explain whether a 30-gallon or 80-gallon tank fits your shop's duty cycle, and can help you spec the right configuration for your electrical service. We've been at this since 2016. Free shipping on this unit, free technical support, and the full Castair manufacturer warranty. If you're deciding between configurations, call us — honest guidance, not a sales pitch.\u003c\/p\u003e\n\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":53342569169109,"sku":"I733HC1-S","price":6793.28,"currency_code":"USD","in_stock":true}],"url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-7hp-3-phase-industrial-air-compressor-horizontal-tank-w-mounted-starter-i733hc1-s","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}