Terminals - Screw Connectors

Part Number	Description / PDF	Quantity
1536 Keystone Electronics Corp.	TERM BINDING POST 8-32 1PIN PCB	1011441
7758 Keystone Electronics Corp.	60-SCREW CAPTIVATED SCREW TERMIN	1950200
7771-6 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB	200
8174 Keystone Electronics Corp.	TERM SCREW 10-32 4 PIN PCB	28331800
7788 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB	2810
7779 Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB RA	2147483647
8198-4 Keystone Electronics Corp.	TERM SCREW 6-32 2 PIN PCB	100
7757-4 Keystone Electronics Corp.	90-SCREW CAPTIVATED TERMINAL W/	1000200
8183-2 Keystone Electronics Corp.	90 6-32 SCREW TERMINAL W/ RED SC	200021700
8199-3 Keystone Electronics Corp.	TERM SCREW 6-32 6 PIN PCB	1900
7697-4 Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	7000
7702-7 Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	400
7701-SEMS Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	1600
8198-5 Keystone Electronics Corp.	TERM SCREW 6-32 2 PIN PCB	100
1232 Keystone Electronics Corp.	TERM SCREW 6-32 2 PIN PCB	1361400
7791 Keystone Electronics Corp.	TERM SCREW 10-32 4 PIN PCB	991
7790 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	9662
7698-3 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB	0
7691-4 Keystone Electronics Corp.	TERM SCREW 6-32 4 PIN PCB	7100
7689-4 Keystone Electronics Corp.	TERM SCREW M3 4 PIN PCB RA	800

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.