Circular Connectors

Circular Connectors - Contacts

Part Number	Description / PDF	Quantity
SA3349/1 Bulgin	CONTACT SOCKET 20-24AWG 1=10PC	216
SA3544/S Bulgin	CONTACT SOCKET 18-20AWG 1=10PC	187
SA3148/1 Bulgin	CONTACT PIN 20-24AWG 1=10PC	30
SA3624/S Bulgin	CONTACT SOCKET 14-18AWG 1=10PC	104
SA3544/P Bulgin	CONTACT PIN 18-20AWG CRIMP 1=10	218
SA3347/1 Bulgin	CONTACT SOCKET 22-26AWG 1=10PC	811
SA3348 Bulgin	CONTACT PIN 22-26AWG 1=10PC	0
SA3180/1 Bulgin	CONTACT PIN 24-28AWG 1=10PC	0
SA3545/S Bulgin	CONTACT SOCKET 14-18AWG 1=10PC	0
SA3149/1 Bulgin	CONTACT SOCKET 20-24AWG 1=10PC	0
SA3347 Bulgin	CONTACT SOCKET 22-26AWG 1=10PC	0
SA3180 Bulgin	CONTACT PIN 24-28AWG 1=10PC	22
SA3623/S Bulgin	CONTACT SOCKET 18-20AWG 1=10PC	2
SA3179 Bulgin	CONTACT SOCKET 24-28AWG 1=10PC	349
SA3542/P Bulgin	CONTACT PIN 22-26AWG 1=10PC	94
SA3622/P Bulgin	CONTACT PIN 22-26AWG 1=10PC	30
SA3349 Bulgin	CONTACT SOCKET 20-24AWG 1=10PC	172
SA3348/1 Bulgin	CONTACT PIN 22-26AWG 1=10PC	0
SA3542/S Bulgin	CONTACT SOCKET 22-26AWG 1=10PC	28
SA3624/P Bulgin	CONTACT PIN 14-18AWG 1=10PC	106

Circular Connectors - Contacts

1. Overview

Circular connectors - contacts are electro-mechanical components designed to establish electrical connections between circuits in a circular interface configuration. These contacts serve as critical conduits for power, signal, or data transmission in complex systems. Their importance spans across industries requiring reliable connectivity in harsh environments, including aerospace, industrial automation, and medical devices. Modern advancements demand miniaturization, higher bandwidth, and improved durability in these components.

2. Main Types & Functional Classification

Type	Functional Characteristics	Application Examples
Power Contacts	High current capacity (up to 100A), thermal resistance	Industrial machinery, EV charging stations
Signal Contacts	Low noise, impedance control	Telecom equipment, control systems
Coaxial Contacts	50/75 impedance, EMI shielding	Radar systems, test equipment
Fiber Optic Contacts	Low insertion loss, multi-channel transmission	High-speed data networks, avionics
Hybrid Contacts	Combined power/signal/data in single interface	Autonomous vehicle sensors, robotics

3. Structure & Composition

Typical construction includes:

Contact pins/sockets: Copper alloys (phosphor bronze, beryllium copper) with plating (gold, silver, tin)
Insulation housing: Thermoplastic (LCP, PBT) or thermoset materials
Shell: Aluminum, stainless steel, or composite materials
Contact retention system: Spring-loaded mechanisms for vibration resistance
Environmental seals: Elastomer gaskets for IP67+ protection

Modular designs allow mixed contact configurations with polarization keys to prevent mis-mating.

4. Key Technical Specifications

Parameter	Typical Range	Importance
Current Rating	1-100A	Determines power transmission capability
Voltage Rating	50-1500V	Safety and insulation performance
Contact Resistance	1-15m	Signal integrity and power efficiency
Insulation Resistance	100M -10G	EI/EMC compliance
Temperature Range	-65 C to +200 C	Environmental durability
Mating Cycles	500-10,000	Service life and reliability

5. Application Fields

Aerospace: Flight control systems, in-flight entertainment
Industrial Automation: Robotics, CNC machines
Medical Equipment: MRI scanners, patient monitoring systems
Transportation: Rail signaling, automotive sensors
Defense: Radar systems, secure communications

Case Study: In wind turbines, circular connectors handle pitch control signals with IP68 protection against dust/moisture.

6. Leading Manufacturers

Manufacturer	Representative Product	Key Features
Amphenol	Series 800 Circular	High-speed data transmission up to 10Gbps
TE Connectivity	DEUTSCH DT Series	Extreme temperature resistance (-65 C to +200 C)
Molex	Circular MIL-DTL-38999	Shock/vibration rated for military vehicles
Delphi	Mini-Circular Connector	Compact design for automotive sensor networks

7. Selection Guidelines

Key considerations:

Current/voltage requirements vs. contact material properties
Environmental protection level (IP rating)
Mating/unmating force requirements
Signal integrity needs (frequency, crosstalk)
Compliance with standards (MIL-DTL-38999, IEC 61076)
Cost vs. lifecycle trade-offs

Recommendation: Aerospace applications should prioritize weight reduction with composite shells, while industrial uses need corrosion-resistant plating.

8. Industry Trends

Emerging developments include:

Micro-miniaturization for IoT device integration
High-speed contacts supporting 40+ Gbps data rates
Smart connectors with integrated sensors
Alternative plating materials (nanocoatings) for RoHS compliance
Modular hybrid designs combining power/optical contacts

Market growth driven by 5G infrastructure and electric vehicle adoption, projected CAGR of 6.8% (2023-2030).