Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691701320002B Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	444
691367110003 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, HOR	480
691359340003 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, HOR	240
691386700010 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, H	99
691317410002 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK HEADER, H	539
691321100007 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK HEADER, V	678
691304100009 Würth Elektronik Midcom	WR-TBL SERIES 3041_3.50 MM_SCREW	370
691335510012 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	0
691305340002 Würth Elektronik Midcom	TERM BLOCK HEADER 2POS 90 3.8MM	890
691318700005 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, V	337
691321300007 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	680
691353500012 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, VER	55
691317510006 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	300
691309310007 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	434
691352410007 Würth Elektronik Midcom	TERM BLOCK PLUG 7POS 7.62MM	100
691309410006 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK HEADER, H	230
691311700007 Würth Elektronik Midcom	TERM BLOCK HDR 7POS VERT 5MM	466
691701550004B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	500
691311500116 Würth Elektronik Midcom	TERM BLOCK HDR 16POS VERT 5.08MM	169
691345510008 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK PLUG, HOR	75

Terminal Blocks - Headers, Plugs and Sockets

1. Overview

Terminal blocks, headers, plugs, and sockets are essential components in electrical and electronic systems for establishing reliable connections between circuits. These devices enable signal transmission, power distribution, and system modularity. Their standardized designs ensure interoperability, scalability, and ease of maintenance in complex systems.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Terminal Blocks	Screw/clamp-based connections for high current/ voltage	Industrial control panels, power distribution units
PCB Headers	Pin/grid arrays for board-to-board connections	Embedded systems, Arduino shields
RJ Connectors	Modular jacks for data/telecom signals	Ethernet networks (RJ45), telephone systems (RJ11)
D-Sub Connectors	Multi-pin trapezoidal shells for analog/digital signals	Legacy serial interfaces, industrial sensors
USB Connectors	Hot-pluggable interfaces for power/data	Consumer electronics, peripheral devices

3. Structure and Components

Typical structures include:

Insulating housing (PA66, PBT, or LCP plastics)
Contact elements (phosphor bronze, beryllium copper)
Plating materials (gold, tin, nickel for corrosion resistance)
Actuation mechanisms (screws, spring clamps, or friction fits)
EMI shielding layers (for high-frequency applications)

4. Key Technical Specifications

Parameter	Importance
Current Rating (A)	Determines power handling capacity
Voltage Rating (V)	Defines dielectric strength requirements
Contact Resistance (m )	Impacts signal integrity and power loss
Insertion Loss (dB)	Critical for high-speed data transmission
Mating Cycles	Indicates mechanical durability
Operating Temperature (- C to + C)	Defines environmental tolerance

5. Application Fields

Primary industries include:

Industrial automation (PLCs, HMIs)
Telecommunications (5G base stations, routers)
Consumer electronics (smartphones, wearables)
Medical equipment (imaging devices, patient monitors)
Automotive (EV charging systems, ADAS)

6. Leading Manufacturers and Products

Manufacturer	Representative Product
Phoenix Contact	COMBICON series terminal blocks
TE Connectivity	MICRO MATCH connectors
Molex	SL Series headers
Amphenol	D-Subminiature connectors
Samtec	QTE high-speed socket systems

7. Selection Guidelines

Key considerations:

Electrical requirements (current/voltage levels)
Mechanical constraints (space, vibration)
Environmental factors (temperature, humidity)
Signal integrity needs (frequency, noise rejection)
Cost vs. reliability trade-offs
Compliance with standards (IPC, IEC, UL)

8. Industry Trends

Emerging developments include:

Miniaturization for wearable devices
High-speed connectors for 5G/6G ( 25 Gbps)
Hybrid connectors integrating power/data
Eco-friendly materials (halogen-free, RoHS compliant)
Smart connectors with built-in sensors
Automotive-grade connectors for EVs