CONDUCTIVE SLIP RING

Introduction

Slip rings are devices that play a pivotal role in varying industries including medical imaging, aerospace, defense, and manufacturing, among many others. They are also referred to as rotary electrical interfaces, rotating electrical connectors, swivels, collectors, or electric swivels. Notably, the underlying premise of a slip ring is to enable the transmission of power and electrical signals from a stationary unit to a rotating object. This amazing feat allows continual 360-degree rotation without the hindrance of tangled wires.

Among many different specifications and parameters associated with slip rings, one significant component known for its functionality is the Outer Diameter (OD) or more commonly, the Slip Ring OD. Measured in millimeters or inches depending on the locale, the OD is an essential factor that governs the design and operation of the slip ring. It has direct implications on the amount of current that can be transferred, the complexity of signal communication, and the overall size and format of the slip ring.

The choice of the right Slip Ring OD is dependent on a multitude of factors including application requirements, design constraints, and operational performance. Thus, it is crucial to have a comprehensive understanding of Slip Ring OD to make the right choice for achieving optimal operation. This article aims to elucidate the concept of Slip Ring OD, discussing its importance, aspects of choosing the right OD, its implications on slip ring performance, and tips to keep in mind while purchasing a slip ring.

What Is Slip Ring OD?

When discussing the components and dimensions of a slip ring, one critical parameter is the Outer Diameter or the Slip Ring OD. This measurement refers to the total distance across the slip ring through its central point, which gives the size of the slip ring from one end to the other while passing through the center.

In terms of structural design, the OD plays a fundamental role because it determines how much space is available for the incorporation of various components within the slip ring. This might include a house for conductive rings, circuits, and wires. These elements are the core carriers of power and signals – the more space for these vital components, the more robust the power or signal transmission capabilities of the slip ring can be.

The dimension of the Slip Ring OD can widely range, from just a few millimeters to several meters based on its intended face of application. For instance, a large OD, which hypothetically means a larger slip ring, can accommodate more circuits or enhance the current-carrying capacity. It’s important to remember this isn’t always feasible or beneficial because increasing the size can lead to other design challenges.

On the contrary, where space is at a premium, such as aerospace or medical applications, a smaller OD would be more appropriate. However, this also means a compromise on the number of circuits or the amount of power that can be transmitted through the slip ring. Therefore, there’s a constant juggling and striking a balance between spatial constraints and operational needs when deciding on the Slip Ring OD.

Understanding the concept of Slip Ring OD and how it influences the slip ring’s operational capacity can guide engineers, manufacturers, and consumers toward making a more informed decision in the selection and utility of slip rings.

How to Choose the Appropriate Slip Ring OD?

Choosing the appropriate Slip Ring OD is a task that involves careful consideration of various factors that directly impact the slip ring’s performance in its intended application. Here are several factors that should be considered:

Understanding Your Application Needs

The first step is to have a clear perspective of your application requirements. What will the slip ring be used for? How much power or how many signal varieties does it need to transfer? For instance, applications that require more circuits or high-power transmission may need a larger OD to accommodate more wires and conductive rings.

Consider the Mechanical Space Constraints

The available space and mechanical limitations greatly influence the choice of OD. Slip rings with larger ODs may not fit well into compact spaces. Hence, it’s essential to ensure that the chosen OD fits neatly within the mechanical size constraints of your application.

Operational Speed

Higher rotational speeds and larger ODs may not always be compatible. This is because larger diameters result in higher centrifugal forces at increased rotational speeds, which can adversely affect the slip ring’s reliability and lifespan. Hence, the operational speed must be considered in light of the slip ring OD.

Balancing Performance with Size

An ideal slip ring will balance the need for high performance with practical size constraints. For instance, disk-type slip rings can have a large OD providing ample space for circuits, but may not be suitable for high-speed applications due to increased centrifugal forces. Therefore, it’s necessary to seek the right balance between size and functionality.

Customizability

Sometimes, standard ODs might not meet specific application requirements. In such cases, look for manufacturers that offer customization options where the OD can be scaled to your exact needs.

By keeping these factors at the forefront, one can make a well-informed decision when selecting a slip ring. Balancing the trade-offs among the OD, performance capabilities, operating speed, and the application’s space constraints can drive toward an optimal choice.

Application of Slip Ring OD with Different Values

The Outer Diameter (OD) of a slip ring is a crucial factor that influences its appropriate selection depending on the intended application. Slip rings with different OD values are applied across myriad sectors to meet specific functional requirements. Here are a few examples of their applications.

Miniature Slip Rings

Known for their compact size, miniature slip rings often have an OD ranging from a few millimeters. These are commonly used in applications where space is limited yet functionality cannot be compromised. Common uses can be found in medical devices like endoscopes or microscopic cameras where small OD slip rings transmit power and signals into highly compact spaces.

Mid-size Slip Rings

These slip rings feature an intermediate OD and find applications in sectors such as automotive manufacturing, wind power generators, and robotics. These industrial applications often require moderate power transmission, and multiple circuits for signal passing with higher rotation speeds, making mid-size OD slip rings the perfect fit.

Large Industrial Slip Rings

Frequently used in heavy-duty industrial applications like large wind turbines and cranes, large industrial slip rings can feature an OD of several meters. They offer high power transmission, greater current carrying capacity, and can accommodate numerous circuits for complex signal transmission.

Disk-type Slip Rings

Disk slip rings typically hold a larger OD which allows them to house more circuits in a relatively slim form. These are often used in applications where vertical space is constrained, such as in CCTV systems, or in rotary tables favoring a flat design.

Capsule Slip Rings

With an OD range typically between 12.5mm to 54mm, these kinds of slip rings are popular in sectors needing reliable transmission in a compact design. Common applications include speed dome cameras and rotary sensors.

Each OD value is tailored to specific use cases and has its advantages and constraints. Thus, careful consideration of the operational environment and the functional requirements is necessary when choosing from different Slip Ring OD values.

Slip Ring OD and Slip Ring Short Circuit

The Slip Ring OD holds a significant influence on avoiding short circuits in slip ring assemblies. Short circuits can occur when electrical current flows through an unintended pathway, bypassing the proper circuit or conductive pathway, and causing damage or malfunction to the slip ring.

With a larger OD, there is generally more space to work with, which means more room for the layout and placement of wires and conductive rings. This increased space allows for better segregation of the wires and circuits, reducing the risk of short circuits caused by contact between adjacent conductive elements. The increased space can also accommodate thicker insulation layers between individual circuits, ensuring a higher degree of overall electrical safety and isolation.

To mitigate the risks associated with short circuits, the following factors should be carefully managed:

Circuit Segregation: Proper spacing between the conductive elements reduces the chances of unintentional physical contact, leading to short circuits. A larger Slip Ring OD allows for better spacing, thus reducing overlap risks.

Insulation Methods: The insulating materials and methods employed in the slip ring assembly should be compatible with the voltage levels and rotational speed requirements of the application. An appropriately chosen Slip Ring OD can ensure there’s enough space for the required insulation.

Manufacturing Quality: High-quality manufacturing standards and properly chosen materials can reduce the likelihood of irregularities that might lead to short circuits. Ensure the slip ring manufacturer adheres to industry quality standards and uses appropriate materials.

Maintenance Practices: Regular maintenance and inspection of slip rings can identify any signs of wear or damage that might lead to short circuit issues. This preventative approach can help in prolonging the slip ring’s lifespan and mitigate potential problems.

In conclusion, the Slip Ring OD directly impacts the slip ring’s ability to ensure proper circuit segregation and insulation, ultimately reducing the chances of short circuits. Choosing a Slip Ring OD with careful consideration of the application’s requirements can minimize the risk of short circuits and boost overall system safety and reliability.

Slip Ring OD Data of Different Types of Slip Rings

The Outer Diameter (OD) of different types of slip rings can vary significantly based on their application requirements. Here are a few examples:

Through Hole Slip Ring

through bore sliprings

Through hole slip ring is a kind of slip ring with a hole in the center. Same meaning as a through-bar slip ring, sometimes called a hollow shaft slip ring. Through hole slip ring totally meets with continuous transmission of power, signals, weak current, high current, and high voltage under 360-degree unrestrained rotations. Low torque, low electrical noise, low loss, and easy maintenance as the main features.

The process of manufacturing and principle are similar to other slip rings. Power, signals, and other data are transmitted from the fixed position to the rotating position through the contact between the brush and the contact. Gold brush and contact will increase the working life. The basic technical parameters of a hole/bore slip ring mainly include bore outer diameter, bore inner diameter, length, circuits, voltage, current, maximum speed, etc. The length is variable and can be customized arbitrarily, while the outer diameter and inner diameter have some standard dimensions in through hole electrical slip rings industry. The number of circuits is the one core parameter for this series of products, the larger the number of circuits, the more complex the manufacturing process, and the higher the price cost.

Model

Picture

No. of Rings

ID(mm)

OD(mm)

Rated Current

Rated Voltage

PDF

1-12

12

33

2A

0~240V

1-24

12

54

5A

0~240V

1-10

20

60

2A~10A

0~380V

1-48

25.4

78

2A~10A

0~380V

1-48

38.1

99

2A~15A

0~380V

1-10

50

75

2A~12A

0~380V

1-72

50

120

5A~20A

0~380V

1-96

60

135

5A~20A

0~380V

1-96

70

155

5A~20A

0~380V

1-96

80

180

5A~20A

0~380V

1-96

90

190

5A~20A

0~380V

1-96

100

203

5A~20A

0~380V

1-96

120

250

5A~20A

0~380V

1-96

150

300

5A~20A

0~380V

1-96

180

332

5A~20A

0~380V

1-96

200

350

5A~20A

0~380V

1-96

250

407

5A~20A

0~380V

1-96

300

490

5A~20A

0~380V

1-96

400

632

5A~20A

0~380V

Ethernet Slip Ring

Ethernet slip rings

Ethernet slip rings are slip rings with Ethernet connectors that allow to transmission of Ethernet protocol through a rotating interface. Ethernet hybrid slip rings run power, signal, and Ethernet from stationary structures to rotating platforms through copper or gold channels. Can mix electrical power and signals, and also transmit multi-channel low-frequency signals and currents.

Ethernet slip ring suitable for 10/100/1000 Base T transmission and usually equipped with RJ45 connector assemblies for plug and play. M12, CAT5E, or CAT6 cables are available as options. Gigabit ethernet slip rings can be used in wind turbines, industrial robots, and radar antennae which need rotary platforms.

Model

100/1000M Ethernet

No. of Electrical

ID(mm)

OD(mm)

PDF

1-3

1-26

--

22

1-3

1-40

--

25

1-2

1-24

25.4

78

1-2

1-24

38.1

99

1-3

1-72

50

120

1-3

1-72

60

135

Pancake Slip Ring

flat sliprings

The pancake slip ring is similar to through through-hole slip ring but is especially used for the rotating system with a height limit. Also called flat slip ring, flat disc electrical slip ring, or platter slip ring, since the shape is similar to a platter, rings, and brushes contact around the center of the circle. Pancake slip ring components include stator, rotor, and contacts, mainly used for transmitting precise signals and power or combined with pneumatic and hydraulic media. More electrical power, current, and signal circuits can extend broadwise limitless on flat diameter.

Pancake slip rings can be configured in two types, integrated and separated.

Integrated ring types can be designed for solid or through-hole rotating systems.

The separated ring type is composed of a separated rotor and contact brush, which can be designed with PCB.

Model

ID(mm)

OD(mm)

No. of Rings

RPM

Thickness

IP

PDF

HP060-6

60

244

6

0~250

35 mm

IP51

HP085-10

85

180

10

0~300

16 mm

IP54

HP220-18-2RF

32

240

18

0~50

32.5 mm

IP51

High Temperature Slip Ring

high temperature slip ring

The slip ring can work stably under a 100~250℃ high-temperature environment, even above 250℃.

Model

No. of Rings

ID(mm)

OD(mm)

Rated Current

Rated Voltage

PDF

1-12

12.0

33.0

2A

0~240V

1-24

12.7

54.0

5A

0~240V

1-10

20.0

60.0

2A~10A

0~380V

1-48

25.4

78.0

2A~10A

0~380V

1-48

38.1

99.0

2A~15A

0~380V

1-72

50.0

120.0

5A~20A

0~380V

1-96

60.0

135.0

5A~20A

0~380V

1-96

70.0

155.0

5A~20A

0~380V

1-96

80.0

180.0

5A~20A

0~380V

1-96

90.0

190.0

5A~20A

0~380V

1-96

100.0

203.0

5A~20A

0~380V

1-96

120.0

250.0

5A~20A

0~380V

1-96

150.0

300.0

5A~20A

0~380V

1-96

180.0

332.0

5A~20A

0~380V

1-96

200.0

350.0

5A~20A

0~380V

1-96

250.0

407.0

5A~20A

0~380V

1-96

300.0

490.0

5A~20A

0~380V

1-96

400.0

632.0

5A~20A

0~380V

USB Slip Ring

USB slip ring

A USB slip ring is specially designed to transmit USB1.0/USB2.0/USB3.0 signals through a rotating interface. USB 2.0 slip rings are widely used in all kinds of communication systems since the USB interface is very popular and convenient for HD video and super-large storage devices. The new generation slip ring for standard USB 3.0 provides a theoretical transmission rate of 5Gbps.

Model

USB Channels

Electrical Rings

ID(mm)

OD(mm)

PDF

UHM025

1~3

32~22

--

25

UHG1254

1~4

1~18

12

54

UHG2578

1~4

1~18

25

78

UHG3899

1~4

1~18

38

99

UHG50120

1~4

1~18

50

120

UHG60135

1~4

1~18

60

135

UHG70155

1~4

1~18

70

155

UHG80180

1~5

1~43

80

180

UHG90190

1~5

1~43

90

190

UHG100203

1~5

1~43

100

203

High Speed Slip Ring

electrical high speed slip ring

A slip ring can reach 2000 rpm and work stable, even above 4000 rpm.

Model

No. of Rings

ID(mm)

OD(mm)

Max Speed

PDF

3

--

12

800 rpm

10

8

54

2000 rpm

10

20

78

2000 rpm

10

35

99

2000 rpm

10

45

120

2000 rpm

10

55

135

2000 rpm

18

--

30

2000 rpm

36

--

33

2000 rpm

High Voltage/High Current Slip Ring

large current slip ring

High Voltage/High Current Slip Ring are used for communication devices, large machining centers, antenna radar systems, large cranes, mining machines, and large cable reels. High voltage sometimes requires more than 2,000 volts and high current sometimes requires 500 amperes.

Model

ID(mm)

OD(mm)

No. of Rings

Max Rated Current

PDF

50

135

4

280A

66

202

20

500A

70

176

8

100A

75

185

98

1000A

75

190

4

400A

80

180

3

250A

Waterproof Slip Ring

IP68 waterproof slip ring

A waterproof slip ring is especially for working under moisture, corrosion, and underwater. The protection grade will be IP65, IP67, and IP68, and the liquid components in the working environment such as freshwater, seawater, oil should be considered. Waterproof slip rings are widely used in ships, harbor equipment, and some water or moisture environment working conditions. The units work well for transmitting precision signals, and electrical power.

Model

No. of Rings

ID(mm)

OD(mm)

IP

PDF

1-36

--

22.0

65

1-82

--

25.0

65

1-5

--

32.0

68

1-48

25.4

78.0

68

1-48

38.1

99.0

68

1-72

50.0

120.0

68

1-96

60.0

135.0

68

1-96

70.0

155.0

68

1-96

80.0

180.0

68

1-96

100.0

203.0

68

CAN Bus Slip Ring

Ethernet slip ring

The industrial bus type mainly solves the digital communication between the field equipment such as intelligent instruments, controllers, and actuators in the industrial field, as well as the information transfer between these field control equipment and the advanced control system. The bus design will directly affect the performance, reliability, expansibility, and upgradability of the whole microcomputer system.

Model

No. of Electrical

ID(mm)

OD(mm)

PDF

1-36

--

22

1-82

--

25

1-24

12.7

54

1-24

25.4

78

1-24

38.1

99

1-72

50

120

1-72

60

135

1-72

70

155

Servo Encoder Slip Ring

servo encoder slip ring

The servo encoder slip ring is an electrical slip ring that works for the servo encoder signal and servo motor power supply. The servo encoder slip ring can save many cables and installation works to transmit data and power. Suitable for all kinds of servo/stepper motors. Supplies usually use gold contacts to avoid external interference and internal interference.

Model

No. of Servo Motor

Max rings

ID(mm)

OD(mm)

PDF

BHG2578-22

1-2

22

25

78

BHG70155-12

1-2

12

70

155

BHG3899-39

1-3

39

38

99

BHG50120-30

1-3

30

50

120

BHG1254-24

1-4

24

12

54

BHT078-36

1-4

36

--

78

BHG60135-38

1-4

38

60

135

BHG80180-33

1-4

33

80

180

BHT085-51

1-4

51

--

85

Capsule Slip Ring

capsule slip ring

Capsule slip rings are often offered in a compact size with flange-like miniature slip rings, used for electrical power transmission and data transfer between a stationary and a rotating part. Capsule Slip Rings also have the rotor, stator, brush block, bearing, and housing. They are easily installed and widely used in small and medium-sized equipment, such as speed dome cameras, intelligent toys, stage lights, drones, etc.

Model

Picture

No. of Rings

Rated Current

Rated Voltage

OD(mm)

RPM

PDF

4-12

1A

240V

6.5

0~250

6-18

2A~10A

240V

12

0~250

6-24

2A~10A

240V

15

0~250

12-18

2A~20A

240V

20

0~250

6-36

2A~20A

240V

22

0~250

30-82

2A~20A

240V

25

0~250

Miniature Slip Ring

mini slip ring

A miniature slip ring assembly is specially designed for small installation spaces. Also called a small slip ring, mini slip ring, compact slip ring, or micro slip ring. A miniature slip ring is the extension of a capsule slip ring through the bore slip ring. The miniature package units have been designed to offer an economical and compact solution for signal and power transmission between the rotor and stator side. Shaft or flange are the two main mounting methods.

Model

Picture

No. of Rings

OD(mm)

Rated Current

Rated Voltage

RPM

PDF

4-12

6.5

1A

240V

0~250

4-12

12

1A

240V

0~250

4-18

15

1A

240V

0~250

6-18

12

2A~10A

240V

0~250

6-24

15

2A~10A

240V

0~250

12-18

20

2A~25A

240V

0~250

PIN Slip Ring

PIN Mercury slip ring

PIN slip rings are the substitute for mercury slip rings. Mercury slip rings use liquid metal mercury as the transmission medium. Special sealing technology, insulation, and compact design made them outstanding features like extremely long working life, low electrical noise, and contact resistance. Mercury is a chronic toxic substance. There have great potential threat to both the environment and the operators if leaked. People have been actively searching for alternative products.

Model

Picture

No. of Rings

OD(mm)

Rated Current

RPM

IP

PDF

2

32

20A

0~400

IP54

2

32

20A

0~400

IP65

2

32

20A

0~400

IP68

3

32

5A/20A

0~400

IP54

3

32

5A/20A

0~400

IP65

3

32

5A/20A

0~400

IP68

4

32

5A/20A

0~400

IP54

4

32

5A/20A

0~400

IP65

4

32

5A/20A

0~400

IP68

5

32

5A/20A

0~400

IP54

5

32

5A/20A

0~400

IP65

5

32

5A/20A

0~400

IP68

HDMI Slip Ring

HDMI slip ring

HDMI slip ring is based on an HDMI connector and transmits data and power between the rotor side and the stator side. HDMI and 3G-SDI slip rings provide the best solutions for transferring high-definition images and voice in a rotating system. Widely used in broadcast television, photography, and video as well the new technology like VR.

Model

No. of HD-SDI

Frequency rate

Power Rings

Signal Rings

OD(mm)

PDF

1

DC-1.5 GHz

4

30

25

3

DC-1.5 GHz

4

28

25

1

DC-3 GHz

3

20

54

1

DC-3 GHz

3

20

78

1

DC-3 GHz

3

20

99

Fiber Optic Rotary Joint

2 channel FORJ

The fiber optic rotary joint (FORJ) is also called the fiber optic slip ring. Optic rotary joints FORJ help to transmit optical communication, like electrical slip rings are used to transmit electrical power and signals. FORJ provides a connection for uninterrupted transmission of optical signals across rotating interfaces. It is especially good for high-speed data transfer on many applications. The key parameters are Insertion Loss, Insertion Loss Variation, and Return Loss.

RF Rotary Joint

electrical RF slipring

RF rotary joint is the abbreviation of radio frequency, used to transmit radio frequency signals between rotor and stator parts in a rotary system. RF rotary joints can be divided into three types, coaxial rotary joints, waveguide rotary joints, and waveguide to coaxial rotary joints. The possible applications range from radar antennae to military, air traffic control, and space. It is often necessary to receive and send multiple-frequency signals.

Model

Frequency Rate(GHz)

No. of  RF Channels

No. of Electrical Rings

OD(mm)

PDF

DC-18

1

--

14.22

DC-4.5

2

--

32

DC-4.5

2

--

122

DC-18

1

11

54

DC-4.5

2

12

80

14-14.5

2

5

122

14-14.5

2

15

180