Quincy 4103DS12HCB46 QT Pro 10 HP, 120-Gallon Two-Stage Air Compressor (460V, 3-Phase)

This is the 460V build of Quincy's QT Pro 120-gallon horizontal compressor, and the voltage on the end of the model number is not a trivial variant. A 10 HP motor wound for 460V draws roughly half the current of the same motor wound for a lower voltage, which changes the size of the feeder your electrician has to pull, the size of the disconnect, and how far the machine can sit from the panel before voltage drop becomes a design problem. If your building already distributes 460V, this is the version that costs you the least to connect.

Everything downstream of the motor is the same industrial hardware: a belt-driven, splash-lubricated cast-iron two-stage pump running at 1,750 RPM against a 120-gallon horizontal ASME certified receiver, rated by Quincy for 50,000 hours or more of pump life, with a working ceiling of 175 PSI.

Choosing the Voltage Before You Choose the Compressor

Buyers get this wrong more often than any other spec, and it is an expensive mistake because a three-phase motor cannot be reconnected across voltage classes on a whim. Check the panel, not the assumption. A 460V machine on a lower-voltage service will not start properly and will not survive the attempt, and a machine wound for a lower voltage put on 460V will be destroyed in seconds. Quincy publishes no single breaker rating for this unit and instead directs the installer to a certified electrician, which is the correct answer given that the overcurrent device depends on conductor size, run length and local code.

The trade-off worth understanding is that 460V lowers current but raises the consequences of a wiring error, so this is not a plug-in appliance under any circumstances. It is hard-wired equipment installed by a licensed electrician on a properly specified circuit.

Two-Stage Compression, Cooled in the Middle

The pump takes air in two bites rather than one. A large low-pressure cylinder does the bulk of the work, then the charge passes through a high-efficiency finned intercooler before a smaller high-pressure cylinder lifts it the rest of the way to 175 PSI. Cooling between stages is what makes two-stage machines efficient: hot air occupies more volume, so a second stage fed uncooled air burns power moving heat instead of making pressure. The intercooler also condenses out a substantial part of the moisture before it reaches the tank, which is the water that would otherwise end up in your lines.

Built to Run, Not to Burst

At 1,750 RPM the pump is turning slowly by consumer-compressor standards, and slow is the point. Piston speed, bearing load, oil temperature and noise all scale with shaft speed, so a machine that spins half as fast lasts considerably longer under the same demand. Splash lubrication feeds from an extra-capacity oil reserve, giving the oil more thermal mass and a longer working life between changes. The connecting rods are two-piece, keeping the reciprocating assembly simple and rebuildable.

A magnetic starter is fitted, providing thermal overload protection for the motor and proper contactor-controlled starting rather than a direct switch across the supply.

Will It Fit?

The horizontal receiver is what gives this model its unusual proportions: 78" long, 28" wide and just 55" tall, against a weight of 850 lbs. A 120-gallon vertical tank of the same capacity needs a great deal more headroom, so this layout is the one that works under mezzanines, low beams and older buildings with limited ceiling height. Allow clearance at both ends for the drain, the discharge and belt access, and put it on a flat, level, load-bearing floor.

Tank outlet is 1". Size your shop piping from that outlet, not from whatever fitting is nearest the bench, because undersized distribution pipe will strangle the output of a machine like this before it ever reaches the tool. Electrical service, site preparation and permitting are the customer's responsibility.

Perfect For

• Plants and industrial buildings already running 460V three-phase distribution.
• Truck, fleet and heavy equipment shops working long tool-heavy shifts.
• Fabrication and finishing operations where pressure has to stay steady rather than recover between jobs.
• Any installation where the compressor sits a long way from the electrical panel and lower current means cheaper wire.

What's in the Box

The compressor arrives as a complete tank-mounted unit: two-stage cast-iron pump, 1,750 RPM industrial motor, belt drive with guard, finned intercooler, magnetic starter, and the 120-gallon ASME certified horizontal receiver with pressure relief valve and discharge connection. Distribution piping, disconnect, dryer and downstream filtration are not included. Note that the extended warranty described below requires a maintenance kit which is a separate purchase.

Specifications

Certification, Honestly

The receiver is ASME certified, and the manufacturer's data also records a CSA marking. Those cover different ground. A pressure vessel certification speaks to how the tank was designed, welded and inspected against a boiler and pressure vessel code; an electrical safety marking speaks to the motor and control equipment. Holding one says nothing about the other, and neither is a substitute for a site inspection.

When the unit lands, check the markings physically stamped or labelled on it. The data plate is what an inspector, an insurer or a plant safety officer will read, and it is the only version of the claim that travels with the machine. If a specific listing is a condition of your insurance, your local code or your employer's equipment policy, verify it against that plate before the electrician connects anything.

Shipping and Delivery

Freight only, to the lower 48 states. The compressor weighs 850 lbs and travels crated on a pallet, so unloading requires a forklift, a dock, or a terminal pickup you have arranged in advance. A delivery to a residential address attracts a residential fee.

Inspect it on the truck. Look for crushed packaging, oil staining on the pallet, bent guards and a receiver that has moved against its bracing, and note anything you find on the bill of lading before you sign it. Once a clean bill of lading is signed, recovering the cost of transit damage becomes extremely difficult.

Warranty

Coverage begins as a 1-year factory warranty. Quincy will extend that to a 3-year "No Bull" warranty when the manufacturer's conditions are satisfied, and this product's own documentation spells them out: the matching maintenance kit must be purchased at the same time as the compressor, and the unit must be registered with Quincy. The extended term includes on-site and labour service, which is a meaningful difference on a machine that weighs 850 lbs and is not going back to a counter.

Full terms are in the manufacturer's warranty handbook supplied with the unit. Whatever you do, do not strip the pump, motor or starter before a claim is opened. Disassembly before inspection is one of the most common reasons a valid claim gets refused.