Schulz SRP 4008 Dynamic — 7.5 HP Enclosed Rotary Screw, 460 Volt Three-Phase
An acoustic cabinet on a large industrial compressor is expected. On a 7.5 HP machine it is the whole point. This is the compact end of the enclosed Schulz range: 500 lbs, a footprint of 49.4" by 23.6", and 53.5" of height — proportions that take a slot along a wall rather than a share of a working bay — with the sound-attenuated cabinet holding it to 69 dB(A).
Put those together and you have a compressor that can stand in the room where the work happens. Small shops rarely have a plant room to put a machine in, which is exactly why the small machines are the ones that most need to be quiet and narrow. Inside is an oil-injected rotary screw air end producing 25 CFM at 125 PSI on a continuous 100% duty cycle, tank-mounted on a 60-gallon horizontal ASME receiver. This is the 460 Volt three-phase build.
Tall and narrow is a deliberate shape
Most shop compressors are laid out for a plant room, which usually means long and low. This one is arranged the other way: it stands 53.5" high on a 23.6" width, so it occupies a strip of wall rather than a rectangle of floor. In a two-bay workshop, a fabrication corner or a garage that is also a store, that difference decides whether the machine is in the way.
It also puts the working parts at a sensible height. The panel, the sight glass and the drain are where you can see and reach them without kneeling on a cold floor, which is the difference between a maintenance routine that happens and one that gets postponed.
Quiet enough to share a room with
69 dB(A) is roughly conversational volume. That is not silence, and a screw compressor loaded all day is still a presence — but it is a very long way from an unenclosed machine, and it is the level at which people stop arranging the workshop around the compressor. The cabinet is also doing a filtering job: it keeps grinding dust, brake dust and overspray away from the cooler and the belt drive, which are the two things that quietly cost a compressor its efficiency.
Schulz publishes an ambient operating ceiling of 113 °F for this model as well, so a warm corner, an uninsulated store or a mezzanine is inside the declared operating envelope rather than a hope.
Why 25 CFM continuous is more air than it sounds
The 100% duty cycle rating is the specification doing the real work. A piston compressor is rated to run for a fraction of each hour, so its airflow figure is a peak you are meant to discount — and if you do not discount it, you spend the machine's service life early through heat.
This air end has no rest requirement. It is rated to run continuously, which makes 25 CFM at 125 PSI a supply figure rather than a burst figure. When you compare it with the piston machine you are replacing, compare it against that machine's usable output, not the number on its badge. The gap is usually much smaller than the specification sheets suggest, and often the wrong way round.
Will It Fit?
The 2-in-1 layout — air end and receiver as one assembly — means a single object to place, with no separate tank and no interconnecting pipework to have fabricated. Overall it is 49.4" long, 23.6" wide and 53.5" tall at 500 lbs, with a 1/2" tank outlet.
Stand it on a flat, sound slab: the load sits on the mounting feet and an uneven floor will work them loose over a season. Leave clearance around the cabinet for the cooling air it depends on, and enough room to open the panels for servicing.
The supply is 460 Volt three-phase. Schulz records both the amp draw and the recommended breaker as "consult a certified electrician", which is correct rather than evasive, since the cable size follows the length of the run and the local code. Confirming the supply, the panel capacity and the breaker before ordering is the customer's responsibility, and it is what usually determines whether a machine runs the week it arrives.
Control and starting
A 24 Volt microprocessor controller manages the machine, with adjustable operating parameters and a live readout instead of a gauge and an assumption — which is what makes a fault legible on a compressor that will not have a technician standing next to it. The automatic starter carries phase and sequence failure detection: on a three-phase screw, crossed phases turn the air end backwards, and a reversed screw can be ruined in seconds. The starter blocks the start rather than allowing it. A magnetic starter is fitted, and an air filter is supplied.
Perfect For
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Small workshops with no plant room — the enclosure and the narrow footprint are aimed squarely here.
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Two-bay independents upgrading from a piston compressor that never kept up.
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Buildings already on 460 Volt three-phase that need a modest, continuous supply rather than a large one.
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Fabrication corners and finishing areas where a loud machine would make the space unusable.
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Anyone tight on floor space but with wall to spare.
What's in the Box
The complete factory unit: rotary screw air end, TEFC IP55 electric motor, magnetic starter with phase and sequence failure detection, 24 Volt microprocessor controller, air filter, sound-attenuated cabinet, 60-gallon horizontal ASME receiver, oil sight glass and a 1/2" tank outlet.
Not included: the data records no air dryer, no electronic drain valve and no pump low-oil shut-off on this model. Air treatment, drainage, pipework and the electrical connection are all separate items.
Specifications
Footprint and environment
| Overall |
49.4" × 23.6" × 53.5" |
| Weight |
500 lbs |
| Sound level |
69 dB(A), sound-attenuated cabinet |
| Ambient ceiling |
113 °F |
Air end and receiver
| Type |
Rotary screw, oil-injected, belt drive |
| Delivery |
25 CFM at 125 PSI |
| Max pressure |
125 PSI |
| Duty |
Continuous 100% |
| Receiver |
60-gallon horizontal, ASME certified, 2-in-1 tank-mounted |
| Outlet |
1/2" |
Electrical
| Motor |
7.5 HP, TEFC, IP55 |
| Supply |
460 Volt, 3-phase |
| Control circuit |
24 Volt microprocessor controller |
| Starter |
Magnetic, phase and sequence failure detection |
| Amps and breaker |
Recorded as "consult a certified electrician" |
Certification, said straight
The 60-gallon receiver is ASME certified — manufactured and stamped to a recognised pressure-vessel code. On a vessel operating at 125 PSI in a room where people work, that is the assurance that carries weight, and it is what the product data claims.
It claims nothing further. No independent third-party listing is recorded for the packaged machine, meaning the motor, starter, controller and cabinet assessed together as one product, and a pressure-vessel stamp does not stand in for that. We prefer to state the boundary rather than let it blur. Insurers, corporate facilities standards and some local electrical inspectors do ask for that second document on hard-wired plant. If your installation is subject to one of them, ask us before you order and we will confirm in writing what documentation currently exists.
Shipping and receiving
Palletised freight throughout the lower 48 states, with the cost quoted live at checkout against your own address rather than taken from a published table.
Settle the unload in advance. A carrier's obligation stops at the tailgate, so 500 lbs on a pallet needs a forklift or a dock, or a pallet jack where the ground is level and hard. Without any of those, terminal pickup lets you collect from the freight depot in your own time and with your own equipment. Deliveries to a home address are residential and carry a residential fee. Collection from our Schulz pickup point at Acworth, Georgia is also available.
Inspect the pallet before signing, and have any damage written onto the bill of lading while the driver is still there. After a clean signature, a claim becomes very hard to pursue.
Warranty
A 12-month warranty applies, recorded in the specification block as 1 Year consumer and 1 Year commercial.
Keep it by keeping the machine whole. A screw air end that has already been dismantled cannot be assessed for what failed first, and the claim usually ends there. Call, text or chat with us on 866-774-7743, describe the symptom, and let the unit be looked at intact.
