Schulz 560HV20-3: oil-free air, running on a 230V 3-phase supply

Two requirements that rarely arrive in the same machine meet in this one. The pump is oil-free, so nothing in the compression chamber can carry over into the air line. The motor is 3-phase on a 230V supply, which is the service a great many older industrial and light-manufacturing buildings already have. If both of those describe your situation, the list of candidates is short, and this is on it.

The rest of the specification: 5 HP, a 60-gallon horizontal steel tank, 20 CFM at 90 PSI with a ceiling of 120 PSI, and a belt-driven cast iron pump turning at 1,050 RPM.

Why a 3-phase motor suits an oil-free pump in particular

The pairing is not a coincidence of the catalogue. It addresses a specific weakness.

A dry-running pump has no oil film to carry away frictional heat, so it depends on slow speed and iron mass to stay within itself — and it is least happy when it is asked to start, repeatedly, against tank pressure. That is exactly the duty a compressor sees in a clinic, a laboratory or a process line, where a lot of small demands mean the machine cycles many times a day rather than running in long steady stretches.

A 3-phase motor answers that duty. Its torque is continuous rather than pulsed, so it breaks the pump away smoothly instead of jerking it into motion, and it does so without a start capacitor or a centrifugal starting switch — the two components most likely to fail on a single-phase compressor motor after tens of thousands of starts. It also spreads current across three conductors rather than two, so the windings run cooler through a heavy cycling day. On plant nobody visits, fewer things that can fail beats any headline figure.

Confirm the supply before you order

The phase and voltage on this listing are a specification, not a preference. A motor wound for a 230V 3-phase supply will not simply adapt to a different one — mismatched, it draws the wrong current, overheats and takes its insulation with it, and the remedy is a transformer or a new motor on top of freight you have already paid.

The check is quick. Have a certified electrician measure line-to-line at the panel that will feed the machine and confirm both the phase and the voltage, rather than inferring them from the building's age or from a label on other plant. Schulz recommends a 40 Amp breaker for this model — treat that as the manufacturer's starting point and let your electrician size the circuit properly against your conductor, run length and local code. If the measurement comes back as something else, contact us before ordering and we will point you at the correct variant.

Confirm the regulator before you order

Published figures for the regulator differ: the copy that has been on this page lists a built-in regulator switch; the manufacturer specification field we hold records the regulator as No. Both are shown here, each attributed to its source. If a factory-fitted regulator decides your purchase, confirm it with us before ordering and we will get it in writing from Schulz. A regulator can be fitted downstream easily enough — the point is that you should know what arrives in the crate.

Read the pressure band before you commit

Rated flow is 20 CFM at 90 PSI; the maximum is 120 PSI. Within that band it comfortably runs air tools, blow-off and cleaning, pneumatic actuators, laboratory and dental equipment and general shop work.

Above it, it does not. The oil-lubricated two-stage compressors in this range reach considerably higher pressure, and if your work depends on the top of that band — certain plasma cutters, high-pressure test equipment — you want one of those and not this. Buy for the pressure you actually use, and buy the air quality you cannot add afterwards.

Will It Fit?

• Floor: 66.9 inches by 21.3 inches. A long, narrow plan that suits a wall or a plant-room bulkhead rather than a corner.
• Height: 40.6 inches, which is roughly bench height. It passes under shelving and mezzanines and through standard doorways on a pallet truck — a genuine advantage when the destination is a finished building rather than an open workshop.
• Weight: 447 lbs. Schulz publishes no floor loading or slab requirement for this model and none is invented here. On a ground-floor slab it is unremarkable; on a suspended floor, get a qualified opinion before delivery is booked.
• Power: 230V, 3-phase, 40 Amp breaker recommended — see the section above.
• Plumbing: a 1/2-inch tank outlet. Size the downstream line for the flow you intend to draw, not for the fitting.

Verifying the space, the floor and the supply before ordering is the buyer's responsibility.

Inside the tank, not just outside it

The steel receiver carries an internal antibacterial powder coating, and the construction is epoxy coated against corrosion of the pump and tank. Both exist for the same reason: a compressor tank is a cool vessel full of humid air, so it accumulates water, and water on bare steel produces rust in a workshop and a contamination question in a clinic or a food area. Coating the inside of the vessel rather than only painting the outside is a deliberate choice for those rooms. It does not, however, excuse you from draining the tank on a schedule, which remains the maintenance job that repays the least effort.

Perfect For

• Industrial and light-manufacturing buildings with an existing 230V 3-phase supply that need air with no oil in it.
• Laboratories, clinics and dental practices operating from a plant room, where the machine runs unattended and cycles frequently.
• Food handling, packaging and process lines where compressed air contacts the product.
• Facilities teams tired of oil changes on plant they can only reach out of hours.

What Is Fitted

• Oil-free belt-drive cast iron pump, two-stage, 1,050 RPM
• 5 HP electric motor, 230V 3-phase
• 60-gallon horizontal steel air tank with internal antibacterial powder coating
• ASME safety valve and tank drain
• Built-in regulator switch (see the note above)
• Intake air filter
• Swedish steel valves
• Epoxy coated construction
• Pressure gauge
• 1/2-inch tank outlet

Specifications

Output

Motor, pump and power

Tank and dimensions

Certification, stated plainly

The certification recorded for this compressor is ASME, covering the safety valve and the air receiver. That is a pressure-vessel standard, and it is the correct thing to insist on for the component that stores the energy — the one failure mode a compressor has that offers no second chance.

What it is not: an electrical safety listing, or an approval of the assembled machine and its control gear. That boundary matters more on this model than on a workshop compressor, for two reasons at once — it is a fixed 3-phase electrical installation, and it is destined for the kind of room that gets inspected against a facility standard. If a specific listing or approval is required by your regulator, insurer or client, ask us before ordering and we will confirm in writing exactly what this unit carries. We would rather lose an order than have it fail an inspection after it is piped in.

Shipping and Delivery

Freight only, to the lower 48 states, priced live at checkout for your delivery address.

Settle the unload before ordering rather than on the day. Crated, this is a 447 lb pallet: a forklift or pallet jack on firm ground, or a trailer and a collection from the freight terminal. The driver is not able to take it into the building. Residential delivery is offered and carries a fee, shown at checkout before payment. Go over the crate with the driver and write any damage onto the bill of lading before you sign — a clean signature makes a later claim extremely difficult to run.

Schulz collection from Acworth, GA is available. Call, text or chat if you want the supply confirmed, the regulator question settled, or the crate measured against your access route: 866-774-7743.

Warranty

Schulz covers this unit for 1 year. Keep the invoice and note the date it was commissioned.

The rule that decides most claims: leave the pump and motor assembled until one is raised. A machine opened beforehand is normally treated as ineligible, whatever the diagnosis turns out to have been. Contact us and we will take it up with Schulz on your behalf.