Terminal Blocks - Headers, Plugs and Sockets

Part Number	Description / PDF	Quantity
EM256508VR PowerStor (Eaton)	TERM BLOCK PLUG 8POS 5.08MM	0
EM256507HL1 PowerStor (Eaton)	TERM BLOCK PLUG 7POS STR 5.08MM	0
EM256511VL PowerStor (Eaton)	TERM BLOCK PLUG 11POS 5.08MM	0
EM359314VC-BK PowerStor (Eaton)	TERM BLOCK HDR 14POS VERT 3.81MM	0
EM241602 PowerStor (Eaton)	TERM BLOCK PLUG 2POS STR 7.62MM	0
EM221504H PowerStor (Eaton)	TERM BLOCK HDR 4POS 90DEG 5MM	0
EM256507H-BKL1 PowerStor (Eaton)	TERM BLOCK PLUG 7POS STR 5.08MM	0
EM502510 PowerStor (Eaton)	TERM BLOCK HDR 10POS VERT 5MM	0
EM211810H PowerStor (Eaton)	TERM BLOCK PLUG 10POS STR 5.08MM	0
EM359305HC PowerStor (Eaton)	TERM BLOCK HDR 5POS 90DEG 3.81MM	0
EM252509 PowerStor (Eaton)	TERM BLOCK PLUG 9POS STR 5MM	0
EM222106V PowerStor (Eaton)	TERM BLOCK HDR 6POS VERT 3.5MM	0
EM211803H PowerStor (Eaton)	TERM BLOCK PLUG 3POS STR 5.08MM	28
EM252512 PowerStor (Eaton)	TERM BLOCK PLUG 12POS STR 5MM	0
EM257509HO PowerStor (Eaton)	TERM BLOCK HDR 9POS 90DEG 5.08MM	0
EM257504VC PowerStor (Eaton)	TERM BLOCK HDR 4POS VERT 5.08MM	1000
EM501514 PowerStor (Eaton)	TERM BLOCK PLUG 14POS 90DEG 5MM	0
EM359304HC PowerStor (Eaton)	TERM BLOCK HDR 4POS 90DEG 3.81MM	0
EM256507VR PowerStor (Eaton)	TERM BLOCK PLUG 7POS 5.08MM	0
EM358304 PowerStor (Eaton)	TERM BLOCK PLUG 4POS 3.81MM	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