Rotary Systems

Manufacturer information and published contact details

Rotary Systems contact details

Head office and factory

14440 Azurite Street NW
Ramsey, MN 55303
United States

Telephone +1 763 323 1514

Email info@rotarysystems.com

Website rotarysystems.com

Show Rotary Systems headquarters on the map Open in Google Maps →

Contact details as published by Rotary Systems Inc., checked 2026-10-30. Specify Motion is not affiliated with Rotary Systems Inc..

Rotary Systems product lines

Who Rotary Systems is

Rotary Systems Inc. is a Minnesota manufacturer of rotating connections. Its core products are rotary unions, which carry fluids such as coolant, hydraulic oil and air across a rotating joint, and slip rings, which carry electrical power and signals. It also combines the two in slip ring unions. The company is certified to ISO 9001:2015 and marks its products as made in the USA.

For machine builders, Rotary Systems is useful when a rotating axis must pass both fluid and electrical services, because it designs both halves.

History and ownership

The About page says the company has worked with engineers for over two decades, that its staff have a combined 80 years of engineering experience, and that it has custom-built more than 700 unique rotating unions. Its 30,000 sq ft facility can machine parts up to 60 in (1.5 m) in diameter. The website does not name founders, owners or a founding year.

Product portfolio

Slip rings

Rotary Systems publishes current, voltage, speed and bore for each standard slip ring, though not circuit counts.

• The capsule slip rings (SR009, SR010) use gold contacts in anodised aluminium housings, rated 3 A at 150 V DC or 2 A at 250 V DC at up to 750 rpm.
• The through-bore capsules and sealed rings (SR013 to SR018) carry 5 to 10 A at 500 to 600 V AC through bores from 0.503 to 1.50 in (12.8 to 38.1 mm), at 250 to 600 rpm. SR017 and SR018 are sealed to IP65.
• The industrial slip ring SR004 is a covered IP65 ring rated 30 A at 600 V AC with threaded terminals, limited to 50 rpm.
• The separates are rotor and brush-block sets for building into a machine, rated 3 to 10 A at 150 to 210 V DC, with bores from 0.59 to 4.75 in (15 to 121 mm).
• The Ethernet capsule SR020 carries 10/100/1000Base-T Ethernet and PoE at up to 750 rpm.

Rotary unions and slip ring unions

The rotary unions and slip ring unions cover single- and multiple-passage designs, mechanical-seal and hydrostatic types, and timing valves. Combined slip ring unions let one assembly carry fluids, power and signals.

Technologies

Rotary Systems uses two contact metals: silver on higher-current separates and sealed rings, and gold on capsules and low-noise signal rings. Gold suits low-level signals and Ethernet, while silver suits power. Its hydrostatic unions use a fluid film rather than contacting seals, which reduces wear at speed.

For selection help, see how to select a slip ring, how to select a rotary union, capsule vs through-bore vs pancake slip rings and Ethernet through slip rings.

Industries served

The product range fits indexing tables, machine tools, packaging and process equipment, and slow heavy equipment such as mixers and cranes. Ethernet capsules suit robots and inspection systems that need networked devices on the rotating side.

Worked example: choosing between SR004 and a capsule

A slowly rotating mixer needs three-phase power at 20 A and 400 V AC, plus two sensor signals, at 10 rpm. The SR004 (30 A, 600 V AC, 50 rpm, IP65) covers the power circuits with margin. Low-level sensor signals are better carried on separate gold-contact rings, so ask whether a combined build is possible or use a second small capsule for the signals.

Things that catch engineers out

• Speed limits. The 30 A industrial ring is rated to just 50 rpm; high-current rings rarely suit fast axes.
• AC versus DC ratings. Separates are rated in V DC and through-bore rings in V AC; do not assume one rating carries over.
• Mixed services. Putting power and Ethernet in one ring needs shielding and spacing; specify both from the start.

Separates or a housed ring?

Separates (rotor plus brush block) cost less and fit inside your own enclosure, so they suit OEMs building many identical machines who can protect the ring themselves. Housed capsules and sealed rings arrive aligned and protected, which saves assembly time and suits lower volumes or dirty environments. With bores up to 4.75 in, the separates also clear large shafts that no standard capsule can.

Global and UK presence

Rotary Systems lists only its Minnesota facility and no UK office or distributors. UK engineers can contact the company directly. Allow for shipping time and check that connectors and cable standards suit UK and EU machines.

What to send when specifying a slip ring or union

Send the number of circuits, current and voltage per circuit, signal and data types, speed, bore or shaft size, environment and IP rating. For unions, add the media, pressure, flow rate and number of passages.

Specify Motion is independent of Rotary Systems and is not a distributor for the company. Our engineers can help source Rotary Systems products or propose equivalents from our supply network on published figures; see find a replacement or the slip rings hub.

Rotary Systems slip rings

Capsule slip rings

Capsule slip rings (SR009, SR010)

Gold-contact capsule slip rings in anodised aluminium housings rated up to 3 A at 150 V DC (SR009) or 2 A at 250 V DC (SR010), at up to 750 rpm.

Through-bore slip rings

Through-bore capsules and sealed rings (SR013–SR018)

Through-bore slip rings rated 5 to 10 A at 500 to 600 V AC, with bores of 0.503 to 1.50 in (12.8 to 38.1 mm) and 250 to 600 rpm; SR017 and SR018 are sealed to IP65.

High-current slip rings

Industrial slip ring SR004

Covered industrial slip ring rated 30 A at 600 V AC with threaded terminals, IP65 enclosure and 50 rpm maximum for slow-turning heavy equipment.

Open and frameless slip rings

Separates (SR001–SR012)

Separate rotor and brush-block slip rings for building into a machine, 3 to 10 A at 150 to 210 V DC, with silver or gold contacts and bores from 0.59 to 4.75 in (15 to 121 mm).

Ethernet slip rings

Ethernet capsule SR020

Capsule slip ring for 10/100/1000Base-T Ethernet, PoE capable, with gold contacts and low electrical noise at up to 750 rpm.

Rotary unions and hybrid joints

Rotary unions and slip ring unions

Single- and multiple-passage rotary unions (mechanical-seal and hydrostatic types, plus timing valves) and combined slip ring unions that pass fluid, power and signals through one rotating assembly.