Terminals - Screw Connectors

Part Number	Description / PDF	Quantity
8191-SEMS Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	19644500
7761 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	2106213300
7757-5 Keystone Electronics Corp.	90-SCREW CAPTIVATED TERMINAL W/	1000200
7838 Keystone Electronics Corp.	SLIMLINE 60 DEGREE SCREW TERMINA	442515100
7769 Keystone Electronics Corp.	TERM SCREW M4 4 PIN PCB RA	0
8189-SEMS Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	18800
7695-6 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	100
7695-2 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	0
7695-4 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	100
1208 Keystone Electronics Corp.	TERM SCREW 10-32 2 PIN PCB	10400
7691-2 Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	33700
7761-2 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	6700
7696-7 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB	200
7759-5 Keystone Electronics Corp.	45-SCREW CAPTIVATED TERMINAL W/	1500200
7766 Keystone Electronics Corp.	TERM SCREW M4 4 PIN PCB RA	200
7799 Keystone Electronics Corp.	TERM SCREW M4 6 PIN PCB	269813800
7771 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB	7697200
7759-6 Keystone Electronics Corp.	45-SCREW CAPTIVATED TERMINAL W/	1462200
1209 Keystone Electronics Corp.	TERM SCREW 8-32 2 PIN PCB	176
7794 Keystone Electronics Corp.	TERM SCREW M4 4 PIN PCB RA	496100

Terminals - Screw Connectors

1. Overview

Screw connectors are electrical terminals that use screws to clamp and secure conductors, enabling reliable electrical connections. As fundamental components in circuit systems, they ensure stable signal and power transmission. Their importance in modern technology spans industries requiring secure, maintainable connections, including industrial automation, energy systems, and consumer electronics.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
PCB Terminal Blocks	Direct soldering to printed circuit boards, screw-based wire retention	Control panels, industrial sensors
Panel-Mount Terminals	Chassis or panel installation with screw clamping	Power distribution cabinets, HVAC systems
Cage Clamp Terminals	Spring-loaded cage mechanism for quick wire insertion	High-vibration environments like rail transport
DIN Rail Connectors	Standardized mounting on DIN rails for modular systems	Factory automation control cabinets

3. Structure and Components

Typical screw connectors consist of: - Conductive Elements: Brass or phosphor bronze contacts with gold/silver plating for low resistance - Insulation Housing: Thermoplastic materials (e.g., PA66, PBT) with UL94 V-0 flammability rating - Screw System: Stainless steel or nickel-plated screws with torque-limiting design - Wire Stop: Mechanical barrier ensuring proper conductor alignment

4. Key Technical Specifications

Parameter	Importance
Rated Current (10-300A)	Determines power transmission capacity
Rated Voltage (50-1000V)	Defines insulation and safety limits
Contact Resistance (<10m )	Impacts connection efficiency and heating
Insulation Resistance (>100M )	Ensures electrical isolation integrity
Withstand Voltage (2500V/1min)	Safety compliance under overvoltage conditions
Operating Temperature (-60 C to +150 C)	Material stability in extreme environments

5. Application Fields

Industrial Automation: PLC systems, motor drives
Renewable Energy: Solar inverters, wind turbine controls
Transportation: EV charging stations, rail vehicle wiring
Building Systems: HVAC controls, security panels
Test Equipment: Oscilloscope probes, power analyzers

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Phoenix Contact	PT 3.5	Modular design, vibration-resistant
Weidm ller	SAM series	Space-saving, 130mm capacity
TE Connectivity	MicroSpeed	High-density PCB terminals
WAGO	280 Series	Cage-clamp technology, tool-free

7. Selection Guidelines

Key considerations:

Electrical requirements (current, voltage, frequency)
Environmental conditions (temperature, humidity, vibration)
Wire size compatibility (AWG/mm specifications)
Certifications (UL, CE, RoHS compliance)
Maintenance accessibility (screw torque requirements)
Cost vs. longevity trade-offs

8. Industry Trends

Emerging developments include: miniaturization for IoT devices, smart connectors with integrated sensors, graphene-enhanced contacts for higher conductivity, and automated screwdriver systems for mass production. Environmental regulations are driving halogen-free insulation materials, while Industry 4.0 demands connectors with embedded diagnostics capabilities.