Schulz SRP 3015 Compact — 15 HP Screw with Phase and Sequence Failure Detection, 230 Volt

There is a failure mode that ends screw compressors in their first minute of life, and almost nothing on a spec sheet warns you about it. If the incoming three-phase supply is connected with two phases crossed, the air end turns backwards. A screw unit run in reverse loses its oil feed and its sealing at the same moment, and the damage is usually done long before anyone gets to the isolator. It is the classic first-power-up disaster, and it is equally possible after any work inside a panel or a change at the supply end.

The SRP 3015 Compact is built to refuse that start. Its automatic starter includes phase and sequence failure detection, so a mis-phased or incorrectly sequenced supply produces a machine that will not run rather than a machine that runs itself to death. That is the feature we would put at the top of this page even though the manufacturer buries it in a bullet list.

The rest is a 15 HP oil-injected rotary screw air end producing 51 CFM at 125 PSI on a continuous 100% duty cycle, belt driven, tank-mounted on a 60-gallon horizontal ASME receiver in an open 2-in-1 frame, on a 230 Volt three-phase supply.

The 24 Volt side of the machine

Behind the protection sits a 24 Volt microprocessor controller, and running the control circuit at 24 Volts rather than at line voltage is a decision with several consequences. It is safer to work around. It allows a display and adjustable operating parameters instead of a fixed pressure switch. And it gives a continuous readout of what the compressor is doing, which is why a fault on one of these tends to be something you read off the panel rather than something you deduce from symptoms.

Between the controller and the starter, most of what usually goes wrong on a shop compressor becomes either visible or impossible. That is a better description of the value here than any output figure.

A note on the supply figures

The model designation and the specification field for this listing both give 230 Volt three-phase. The manufacturer's own motor line describes the same motor as 208-230 Volt three-phase — the same band, stated more widely, so the two are compatible rather than contradictory. Your electrician will still want to verify the actual supply at your panel.

Schulz records the amp draw and the recommended breaker as "consult a certified electrician", and that is the right answer rather than an omission: conductor sizing depends on the length of your run and on local code. Confirming supply, panel capacity and breaker before the machine arrives is the customer's responsibility.

Check the dimensions before you plan the space

Published dimensions for this machine differ, and both sets are shown here. The description gives the machine as 53" long, 18" deep and 42" high. The specification block gives 53" long, 24" wide and 55" high. The length matches; the other two do not.

If it is going into an open corner of a workshop, the difference is academic. If it is going under a mezzanine, into an alcove or through a particular doorway, ask us to confirm against the current factory sheet before you order — and do not plan to the smaller pair on the assumption that they are the newer figures. Confirmed weight is 463 lbs and the tank outlet is 3/4".

What continuous duty is worth

A piston compressor is rated for a share of each hour and must be left alone for the rest of it. This one has no such requirement: the 100% duty cycle rating means it can run every minute of every hour. That is what turns 51 CFM at 125 PSI into a figure you can size an air system against, rather than a peak to be discounted before you start.

The 60-gallon receiver behind it is modest relative to that output, which is precisely what a continuous-duty machine allows — the tank is smoothing demand rather than covering enforced rest periods. An air filter is fitted, the air end is oil lubricated, and a sight glass makes the level check a look rather than a job.

Open frame

No acoustic cabinet is fitted to this model. In practice that means unrestricted cooling and genuinely easy access: belts, drain, sight glass and electrical panel are all where you can reach them, so servicing is quick and a developing problem is visible. It also means the machine is loud enough to be heard across a building. The product data does carry a dBA value, but it is stored as a bare number with no unit attached, and we do not print figures whose units the data has not established. Ask us and we will confirm the current published sound level in writing.

Perfect For

• First-time screw compressor buyers — the starting protection is the safety net that matters on a first installation.
• Sites with older or recently altered three-phase supplies, where phase sequence is not a given.
• Busy service and fabrication shops with a steady multi-tool draw.
• Plant rooms and rear workshops where an open machine's noise is not an issue.
• Owners who maintain their own equipment and value reachable components.

What's in the Box

The complete factory assembly: rotary screw air end, TEFC IP55 electric motor, magnetic starter with phase and sequence failure detection, 24 Volt microprocessor controller, air filter, 60-gallon horizontal ASME receiver, oil sight glass and a 3/4" tank outlet.

Not fitted: no after-cooler, no air dryer and no electronic drain valve are recorded for this model. Air treatment, distribution pipework and the electrical connection are separate.

Specifications

Protection and control

Motor and output

Receiver and size

Certification, honestly

The receiver carries an ASME certification, meaning the pressure vessel was built and stamped to a recognised code. On a tank working at 125 PSI in an occupied workshop that is the assurance that counts, and it is what the data for this product actually claims.

What it does not claim is any independent third-party listing for the machine as an assembled product — motor, starter, controller and frame judged together. A vessel stamp is a different document and we are not going to let the two be confused. Where an insurer, a corporate facilities policy or a local electrical inspector requires that second listing for fixed plant, please raise it with us before ordering and we will put in writing what documentation currently exists.

Delivery and unloading

Freight, on a pallet, to the lower 48 states, with the price quoted live at checkout for your own address rather than estimated in advance.

Have a plan for taking 463 lbs off a truck. Carriers deliver to the tailgate, so a dock or forklift is the straightforward route, with a pallet jack workable on hard, level ground. If your site offers neither, terminal pickup lets you collect from the carrier's depot at your convenience. A home address is treated as a residential delivery and carries a residential fee. Collection from our Schulz pickup point at Acworth, Georgia is also available.

Look the pallet over before you sign for it and note any damage on the bill of lading in the driver's presence. Once a clean signature is on the paperwork, a claim becomes very hard to make.

Warranty

The specification block records 1 Year consumer cover and 1 Year commercial cover on this model. There is nothing additional to purchase to hold it.

The one thing that will void a good claim is a strip-down. A screw air end that has been opened cannot be assessed for what failed first, so please leave it assembled and call, text or chat with us on 866-774-7743 with a description of the fault. We would far rather have the machine looked at whole.