Fingerprint Access Control Board S4 7 to 30V Fingerprint Identification Module with Onboard Relay for Door Lock Control Overview A compact control board designed to add biometric access control to door locks and DIY security projects. The S4 module provides fingerprint identification and an onboard relay for direct control of electric locks, running from a wide 7 to 30V DC supply. It is intended for retrofit and custom installations where reliable, standalone access control is needed. Key benefits Simplifies secure access: replaces or supplements keys and cards with fingerprint identification for authorized entry. Wide input range: accepts 7 to 30V DC so it integrates with common power supplies used in access control systems. Direct lock control: onboard relay switches standard door lock circuits without requiring an external relay. Compact and easy to install: PCB form factor fits into enclosures used in DIY and professional setups. Flexible integration: designed to work with typical electric door hardware and control components. Main features Model: S4 fingerprint control board. Function: biometric fingerprint identification and relaybased door lock control. Power: operates from 7 to 30V DC. Output: onboard relay for lock actuation. Form factor: compact PCB module suitable for mounting inside access control enclosures. Intended use: DIY projects, retrofits, and small access control systems. Compatibility and connections Compatible with standard electric locks and door control components commonly used in access control systems. Integrates with exit buttons, alarms, power supplies, and lock hardware when wired according to system requirements. Designed for easy wiring and installation in both builds and retrofit applications. Performance and reliability Purposebuilt for consistent fingerprint identification and relay switching in everyday access control scenarios. Compact design reduces installation footprint while providing the interface to control locks. Typical applications Residential entry: add fingerprint access to a home electric strike or magnetic lock for keyless entry. Small office or : control staff access to an office, workshop, or utility area without managing keys or cards. Equipment or storage cabinets: restrict access to tools, inventory, or sensitive equipment in a workshop or backroom. Installation notes Provide a stable 7 to 30V DC supply sized to handle the lock and module current draw. Follow standard wiring practices for door locks, exit switches, and power isolation to ensure safe operation. Use an enclosure appropriate for the installation environment to protect the PCB and connections. What you get S4 fingerprint control board module configured for biometric identification and relaybased door lock control. This module is suitable for builders and installers who need a compact, voltageflexible fingerprint controller that directly operates door locks as part of a DIY or small access control system.