Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
691356310008B Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK HEADER, D	210
691312410004 Würth Elektronik Midcom	TERM BLOCK HDR 4POS 90DEG 7.62MM	0
691386700014 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, H	49
691322110007 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK HEADER, H	675
691311500104 Würth Elektronik Midcom	TERM BLOCK HDR 4POS VERT 5.08MM	0
691348300004 Würth Elektronik Midcom	TERM BLOCK PLUG 4POS STR 3.81MM	3
691312510009 Würth Elektronik Midcom	TERM BLOCK HDR 9POS 90DEG 5.08MM	235
691359340012 Würth Elektronik Midcom	3.81 MM TERMINAL BLOCK PLUG, HOR	44
691311400107 Würth Elektronik Midcom	TERM BLOCK HDR 7POS VERT 7.62MM	484
691366110004 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, HOR	526
691333500008 Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, D	115
691311500020 Würth Elektronik Midcom	TERM BLOCK HDR 20POS VERT 5.08MM	60
691304330002 Würth Elektronik Midcom	TERM BLOCK PLUG 2POS 180 3.81MM	0
691313510015 Würth Elektronik Midcom	TERM BLOCK HDR 15P 90DEG 5.08MM	90
691373500016B Würth Elektronik Midcom	TERM BLOCK PLUG 16POS STR 5.08MM	0
691364100012 Würth Elektronik Midcom	3.50 MM TERMINAL BLOCK PLUG, VER	84
691701500002B Würth Elektronik Midcom	5.08 MM TERMINAL BLOCK HEADER, V	229
691304530003 Würth Elektronik Midcom	WR-TBL SERIES 3045_5.08 MM_SCREW	186
691318700004 Würth Elektronik Midcom	5.00 MM TERMINAL BLOCK HEADER, V	272
691304130002 Würth Elektronik Midcom	TERM BLOCK PLUG 2POS 180 3.50MM	175

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