Schulz SRP 4010 Dynamic — 10 HP Rotary Screw on a 120-Gallon Receiver, 208-230 Volt

The interesting thing about this configuration is the ratio. A 10 HP air end delivering 35 CFM has been mounted on a 120-gallon receiver — a far larger volume than a machine of this output strictly needs. That is a deliberate choice, and it is the single best reason to pick this model over a nominally similar one on a smaller tank.

Underneath that is a belt-driven, oil-injected rotary screw air end running a continuous 100% duty cycle at 125 PSI, in a sound-attenuated cabinet rated at 69 dB(A), on a 208-230 Volt three-phase supply. The compressor and the receiver are one 2-in-1 assembly, so the whole thing arrives as a single object to place.

Why the oversized receiver matters

A screw compressor does not stop and start like a piston machine; it loads and unloads. When demand falls it keeps turning but stops making air, and every one of those transitions costs a little energy and puts a little stress on the air end and the oil separation system. A shop with a small receiver and a variable demand can push a screw into loading and unloading constantly — the condition that shortens a screw unit's life faster than anything except running it dry.

Storage is the cure. A large receiver absorbs the peaks, so the machine loads for longer and less often. Pressure at the tools stays flatter, because the tank is buffering the demand rather than the compressor chasing it. And when someone pulls a burst of air for thirty seconds — an impact gun on a stubborn hub, a blowgun on a bench — the tank answers it and the compressor may never notice.

Putting 120 gallons behind 35 CFM is therefore not padding. It is what makes a modest machine behave calmly in a shop with a spiky, real-world air demand rather than a steady industrial one.

Continuous duty, stated plainly

The 100% duty cycle rating is what separates this from a piston compressor of similar output. A reciprocating unit is rated to work part of each hour and rest for the remainder; exceed that and you are spending the machine's service life early. This one is rated to run for the whole hour, every hour. That is why the 35 CFM figure at 125 PSI is usable as a design number rather than a peak to be discounted.

The air end itself is aluminium-bodied and oil-injected with a belt drive, and an after-cooler is fitted, which drops most of the moisture out at the machine instead of leaving it to condense in your pipework. An oil sight glass keeps the routine check to a glance.

Noise and heat

The enclosure brings the machine down to 69 dB(A), which is the level at which a compressor stops dictating the layout of a workshop. Schulz also states an ambient operating limit of 113 °F, so a warm store room, a mezzanine or an uninsulated back bay is inside the declared envelope rather than a hope. Both of those matter more on a small machine than a large one, precisely because a small machine usually ends up somewhere convenient rather than somewhere purpose-built.

Will It Fit?

One object, 58.5" long by 27.6" wide by 39.8" tall, weighing 613 lbs, with a 3/4" tank outlet. Nothing else to plumb together on site.

Set it on a flat, sound slab — the weight is concentrated on the mounting feet, and an uneven floor will slowly work them loose. Keep clear space around the cabinet so the cooling airflow it relies on is not blocked and so the service panels can open properly.

The supply is 208-230 Volt three-phase, which is the low-voltage three-phase service most independent commercial buildings already have. Schulz records both the amp draw and the recommended breaker as "consult a certified electrician". That is the correct answer rather than a missing one: the conductor size follows the length of your run and your local code. Verifying the supply, the available panel capacity and the breaker is the customer's responsibility, and it is worth doing before the order rather than on delivery day.

Control and protection

A 24 Volt microprocessor controller runs the machine. Parameters are adjustable, and the display reports continuously, which is why a fault on one of these is something you read rather than something you infer. The automatic starter includes phase and sequence failure detection: get two phases crossed and a screw air end turns the wrong way, which can ruin it in the time it takes to walk to the isolator. The starter refuses the start instead. A magnetic starter is fitted as standard.

Perfect For

• Independent workshops with uneven air demand — the large receiver is aimed exactly at this.
• Buildings on 208-230 Volt three-phase, without a service upgrade or a transformer.
• Shops replacing a tired piston compressor and wanting the duty cycle rather than a bigger badge number.
• Tyre bays and general service, where short heavy bursts are the daily pattern.
• Anywhere the compressor sits in the working space rather than in a plant room.

What's in the Box

The complete factory unit: aluminium rotary screw air end, after-cooler, TEFC IP55 motor, magnetic starter with phase and sequence failure detection, 24 Volt microprocessor controller, sound-attenuated cabinet, 120-gallon horizontal ASME receiver, oil sight glass and a 3/4" outlet.

Not included: no air dryer and no electronic drain valve are recorded on this model, so a drain routine or the hardware to automate it is yours to arrange, along with pipework, filtration, regulation and the electrical connection.

Specifications

Output and air end

Electrical

Receiver and dimensions

Certification — what is claimed, and what is not

The 120-gallon receiver is ASME certified. The vessel has been built and stamped to a recognised pressure-vessel code, which is the assurance that carries weight on a tank sitting at 125 PSI in a room with people in it.

That is the whole of the claim. Nothing in the product data records an independent third-party safety listing for the machine as an assembled product — the motor, the starter, the controller and the cabinet judged together. A tank stamp is a different document and it does not substitute. Since some insurers, corporate facility rules and local electrical inspectors ask specifically for the latter on permanently wired equipment, ask us first if that describes your situation, and we will confirm in writing what the documentation currently covers.

Freight and receiving

Shipped on a pallet by freight carrier to the lower 48 states. Cost is quoted live at checkout for the address you enter, rather than taken from a published table.

Sort the unload first. The carrier's obligation ends at the tailgate, and 613 lbs is beyond what people and a ramp should attempt — a forklift or a dock is the sensible answer, with a pallet jack acceptable on level, hard standing. If your site has none of that, choose terminal pickup and collect from the freight depot. Home addresses are treated as residential deliveries and carry a residential fee. Collection from our Schulz pickup point in Acworth, Georgia is another option.

Inspect it before signing, and write any damage on the bill of lading while the driver is still with you. That note is what makes a claim possible later.

Warranty

Cover is a 12-month warranty, recorded in the specification block as 1 Year consumer and 1 Year commercial.

If something goes wrong, resist the urge to open it. A screw air end that has already been dismantled cannot be assessed for root cause, and that generally ends the claim before it starts. Contact us on 866-774-7743 with a description of the symptom and let the unit be examined intact.