Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691321300019 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	160
691314520105 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, 4	298
691701500003B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, V	300
691373500007B Würth Elektronik Midcom	TERM BLOCK PLUG 7POS STR 5.08MM	0
691304130004 Würth Elektronik Midcom	TERM BLOCK PLUG 4POS 180 3.50MM	42
691352510016 Würth Elektronik Midcom	TERM BLOCK PLUG 16POS 5.08MM	30
691322110003 Würth Elektronik Midcom	TERM BLOCK HDR 3POS 90DEG 3.5MM	112
691321300010 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, V	523
691701520010B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, V	300
691317410005 Würth Elektronik Midcom	7.62 MM TERMINAL BLOCK HEADER, H	360
691304300004 Würth Elektronik Midcom	WR-TBL SERIES 3043_3.81MM_SCREWL	160
691366110007 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, HOR	332
691361100004 Würth Elektronik Midcom	TERM BLOCK PLUG 4POS STR 3.5MM	4443
691308330008 Würth Elektronik Midcom	TERM BLOCK HDR 8POS VERT 3.81MM	0
691305540005 Würth Elektronik Midcom	WR-TBL SERIES 3055_5.08 MM_PCB H	562
691317510007 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, H	209
691352510020 Würth Elektronik Midcom	TERM BLOCK PLUG 20POS 5.08MM	19
691304130003 Würth Elektronik Midcom	TERM BLOCK PLUG 3POS 180 3.50MM	296
691308330006 Würth Elektronik Midcom	TERM BLOCK HDR 6POS VERT 3.81MM	0
691386700005 Würth Elektronik Midcom	TERM BLOCK HDR 5POS VERT 5MM	0

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