Through-bore slip rings
Senring H Series through-hole slip rings
Through-hole slip rings with metal housings and multi-point brushes, bores from 3 to 300 mm, up to 144 circuits in the standard table (300 optional), 0–20 A per circuit and up to 600 V AC/DC.
Key specifications
| Circuits (max) | 144 |
|---|---|
| Current per circuit (max) | 20 A |
| Voltage (max) | 600 V |
| Bore | 3–300 mm |
| Outer diameter | 16–430 mm |
| Circuits note | standard models up to 144; page states 0–300 circuits optional |
Summarised in our own words from SENRING Electronics Co., Limited's published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1
Notes on this data
Speed, IP and temperature not published on the series page.
Specify Motion is not affiliated with SENRING Electronics Co., Limited. Senring and H Series through-hole slip rings are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Typical applications
Engineer support
Speak to our engineers about your project
Our experienced engineers are on hand, ready to help with your project. Whether you need the Senring H Series through-hole slip rings itself, help sourcing it, or a modified or custom design built around your load, speed and space, tell us what the machine has to do and we'll come back with the right option.
- Help sourcing H Series through-hole slip rings and spares for installed machines
- Modified and custom designs when a catalogue part doesn't fit
- Complete axis: motor, drive, gearing and feedback matched together
What a through-bore slip ring is
A through-bore slip ring is a rotary electrical joint built around a hollow centre, so a drive shaft, pneumatic or hydraulic line, fibre or cable bundle can pass straight through it. The rings are mounted on an insulated sleeve that fits over or around the machine shaft, and the brush blocks sit outside them in a stationary housing. Power, signal and data circuits are combined in one unit, while the bore keeps the rotation axis available for mechanics or services. Bore sizes range from a few millimetres to hundreds of millimetres.
When engineers choose a through-bore slip ring
Engineers choose a through-bore design when the axis of rotation is already occupied, typically by a shaft, a rotary union or a cable that must stay continuous. It is the standard choice for indexing tables, wrapping machines and turntables built around a central column. The trade-off is that larger rings mean higher surface speed, more brush wear and more drag torque at the same rpm, and the unit is bigger than a capsule. Where axial length is the constraint rather than diameter, a pancake design may suit better.
How to specify the Senring H Series through-hole slip rings
Send these with your enquiry and an engineer can confirm the right H Series through-hole slip rings variant or an equivalent:
- Bore diameter and shaft tolerance (mm)
- Outer diameter and length limits (mm)
- Circuit count and current per circuit (A)
- Working voltage and any high-voltage isolation (V)
- Speed, continuous and peak (rpm)
- Data or bus protocols to pass, such as Ethernet, CAN or PROFINET
- Sealing (IP code), temperature (°C) and mounting method
Common mistakes to avoid
- Sizing the bore to the shaft only, with no allowance for a rotary union or cables that must also pass
- Mounting the rotor hard on a shaft with radial runout and a separate stator fixing, so the unit is forced to align two axes
- Forgetting that surface speed rises with diameter, so the rated rpm is lower for larger bores
- Not stating which circuits need screening or twisted pairs for encoder and fieldbus signals
Senring H Series through-hole slip rings: frequently asked questions
What is the Senring H Series through-hole slip rings?
Through-hole slip rings with metal housings and multi-point brushes, bores from 3 to 300 mm, up to 144 circuits in the standard table (300 optional), 0–20 A per circuit and up to 600 V AC/DC. Published series figures include circuits 144, current per circuit 20 A, voltage 600 V, bore 3 mm. It is made by SENRING Electronics Co., Limited; Specify Motion can help source it or propose an equivalent.
Who makes the Senring H Series through-hole slip rings?
The Senring H Series through-hole slip rings is made by Senring (SENRING Electronics Co., Limited) and is listed here for engineers comparing options. Specify Motion is not affiliated with SENRING Electronics Co., Limited; brand names are used only to identify the product.
What is the circuits of the Senring H Series through-hole slip rings?
The published series maximum circuits is 144. Individual models and sizes in the H Series through-hole slip rings 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 Senring H Series through-hole slip rings?
Yes. Our engineers can propose an equivalent built around your load, speed and environment. An engineer confirms the fit against your application before recommending anything.
How do I choose the bore size for a through-bore slip ring?
Start with the shaft diameter and its tolerance, then add anything else that must pass through the centre, such as hoses, a rotary union stem or a fibre. Allow clearance for assembly and for the insulating sleeve. Larger bores raise surface speed, cost and drag torque, so pick the smallest bore that genuinely clears what has to pass through.
Can a through-bore slip ring carry Ethernet as well as power?
Yes. Many through-bore units combine power rings with signal rings designed for industrial Ethernet, using controlled impedance, twisted-pair routing and screening between groups. State the protocol and speed, typically 100 Mbit/s or gigabit, so the supplier can allocate suitable rings and keep them away from motor power. For very high data rates, a contactless or fibre channel may be added.
Further reading: How to select a slip ring · Ethernet through slip rings · Slip rings
Other through-bore slip rings series
Spec builder
Specify what you need instead of H Series through-hole slip rings
Select every part you need, answer the questions an applications engineer would ask, and see your summary before we ask for any details.
- 1Products
- 2Performance
- 3Environment
- 4Volumes
- 5Your spec
Engineer support
Our engineers are ready to help with your project
Tell us about your project and how you use the Senring H Series through-hole slip rings: the load, speed, duty and environment. An experienced engineer will review it and reply, normally within one working day.
- Reviewed by an engineer, not an autoresponder
- Like-for-like and better-fit alternatives
- Standard, modified and custom options
Prefer to configure it? Use the spec builder.