Slip rings
Princetel SRP90 series slip ring
Electrical slip ring designed to pair with Princetel FORJs, carrying 2–10 A per ring at 1,000 V RMS (2,000 V optional) at 500 rpm, with a stainless steel body that takes axial loads of about 0.5 tonne.
Need this part, a replacement or a complete package? Our experienced UK engineering team helps you select, source and obtain the right products, with pricing, delivery coordination and after-sales support.
Pricing and availability
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Need Princetel parts, a replacement or a suitable alternative? Send us a part number, or tell us what the machine needs to do. Our UK engineers will come back with the right product, pricing, lead time and delivery, whether that is the original part, a checked alternative or a complete axis.
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- 1Products
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What are you specifying?
Select everything you need. A motor, drive and gearbox can be specified together as one axis.
Key specifications
| Current per circuit (max) | 10 A |
|---|---|
| Voltage (max) | 2,000 V |
| Speed (max) | 500 rpm |
| Ingress protection | IP60 |
| Temperature | -40–65 °C |
| Weight | 2,500 g |
| Voltage note | 1,000 V RMS standard, 2,000 V optional |
| Contact resistance | <500 mΩ (typ. 50–100 mΩ) |
| Size | 90 mm dia. x 120 mm |
Summarised in our own words from Princetel, Inc.'s published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1
Notes on this data
Ring count is set by part number; 500 rpm is given as rotation speed, not explicitly a maximum.
Specify Motion is not affiliated with Princetel, Inc.. Princetel and SRP90 series are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Princetel SRP90 series replacement and alternative options
Use these supply-network options as a starting point for an engineering check. We can also help source the original Princetel part. Published series figures do not establish an exact-model or drop-in replacement: confirm ratings, fit, interfaces and approvals for your application.
A small analogue power-and-signal slip ring with FASTON quick-connect terminals for fast wiring in dusty, high-cycle machinery. Optional IP65 sealing.
Figures are the highest published for each series and are not always measured the same way. A higher figure is not automatically a better choice: mounting, duty cycle, feedback, connectors and approvals matter too. An engineer will check the fit against your application before recommending anything.
Typical applications
What a slip ring is
This group covers slip rings that do not fit a single standard format, including modular and split designs, contactless capacitive or optical data rings, temperature-rated units, quick-connect terminal designs, very high circuit counts and application-specific assemblies for wind turbines or packaging. All solve the same problem: transferring power, signals or data between stationary and rotating parts of a machine. What differs is the construction, which may be a split housing, a modular stack, a non-contact data path or a special material set.
When engineers choose a slip ring
Engineers look at these designs when a standard capsule, through-bore or pancake unit does not fit the job. Split rings suit retrofits onto existing shafts. Contactless data rings suit high data rates or long life without wear. Modular units allow circuit counts to change between machine variants. The trade-offs are cost, availability and, for custom designs, longer lead times and qualification. Match the construction to the real constraint, whether that is installation, data, temperature or circuit count.
How to specify the Princetel SRP90 series
Send these with your enquiry and an engineer can confirm the right SRP90 series variant or an equivalent:
- What makes the application non-standard: installation, data, temperature, circuit count or format
- Circuits, current and voltage (A, V)
- Data protocols and rates
- Speed (rpm) and expected life (revolutions)
- Bore, envelope and mounting (mm)
- Temperature range (°C) and IP code
- Terminations, such as flying leads, connectors or quick-connect tabs
Common mistakes to avoid
- Choosing a special design when a standard type with minor changes would do
- Not stating the actual constraint, so the supplier offers the wrong format
- Assuming contactless data channels also carry power
- Underestimating lead time for custom or modular builds
Princetel SRP90 series: frequently asked questions
Can you help replace Princetel SRP90 series or source the original?
Send the full model code, quantity and required date. Our engineers can check original-part availability and assess suitable alternatives, including supply-network options where appropriate. We confirm compatibility and any changes needed before recommending a replacement.
What is the Princetel SRP90 series?
Electrical slip ring designed to pair with Princetel FORJs, carrying 2–10 A per ring at 1,000 V RMS (2,000 V optional) at 500 rpm, with a stainless steel body that takes axial loads of about 0.5 tonne. Published series figures include current per circuit 10 A, voltage 2,000 V, speed 500 rpm, temperature -40 °C. It is made by Princetel, Inc.; Specify Motion can help source it or propose an equivalent.
Who makes the Princetel SRP90 series?
The Princetel SRP90 series is made by Princetel (Princetel, Inc.) and is listed here for engineers comparing options. Specify Motion is not affiliated with Princetel, Inc.; brand names are used only to identify the product.
What is the current per circuit of the Princetel SRP90 series?
The published series maximum current per circuit is 10 A. Individual models and sizes in the SRP90 series range vary, so check the exact variant against your duty cycle, mounting and environment, or ask our engineers to confirm the right size for you.
Is there an alternative to the Princetel SRP90 series?
We can assess suitable replacement options. On published figures, Motion Control Products HR Series Faston Type Slip Ring is options to assess from our supply network. An engineer confirms the fit against your application before recommending anything.
What is a split slip ring?
A split slip ring has a rotor and housing made in two halves, so it can be fitted around an existing shaft without removing the shaft or its bearings. It suits retrofits and large machines where disassembly would be costly. Expect tighter installation tolerances and possibly a lower speed rating than a one-piece unit.
What is a contactless slip ring?
A contactless slip ring transfers data, and sometimes power, across rotation without sliding contacts, using capacitive, inductive or optical coupling. There is no wear on the data path, so life is long and very high data rates are possible. Contactless power is usually limited, so many designs combine a contactless data channel with conventional power rings.
Further reading: How to select a slip ring · How to specify a slip ring · Slip rings
Other slip rings series
Engineer support
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Tell us how you use the Princetel SRP90 series: the load, speed, duty and environment. Our engineers will confirm whether it is still the right part, find it for you, or propose an alternative that fits better.
- Reviewed by an engineer, not an autoresponder
- Like-for-like and better-fit alternatives
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Prefer to configure it? Use the spec builder.
How it works
From enquiry to delivery
Send a part number or describe the application. Our engineers take it from there: the right product, a clear quotation, and delivery and support arranged.
- 01Tell us what you needSend a part number, or configure the application, quantities and timing.
- 02An engineer reviews itWe check the specification and find the original part, a checked equivalent or a complete axis.
- 03Receive your quotationProducts, pricing, lead time and compatibility notes in one reply.
- 04Order and deliveryWhen you are happy, the order is placed and delivery and after-sales support are arranged.