Access Control Installation

Survey — What to Assess

1. Number of doors: One door or multiple? Multiple doors require a networked controller; single doors may use a standalone unit.
2. Door type: Timber, steel, aluminium framed? Inward or outward opening? Determines which locking hardware is appropriate.
3. Fail-safe or fail-secure:
   • Fail-safe (fail-open): Door unlocks on power loss — required for fire exit routes. Use maglocks or fail-safe electric strikes.
   • Fail-secure (fail-locked): Door stays locked on power loss — for security doors. Use fail-secure electric strikes.
4. Entry credentials: Keypad (PIN), fob/card (RFID), or combination?
5. Cable routes: Where will power and data cables run from the controller to the door?
6. Integration: Does the access control need to link to the alarm panel or CCTV?

Locking Hardware

Magnetic Locks (Maglocks)

• Mounted at the top of the door frame — electromagnet on the frame, armature plate on the door
• Fail-safe by default: power = locked; no power = open
• Power requirement: typically 12V DC, 500mA–1A
• Bond strength: 280kg (600lb) or 600kg (1300lb) — select based on security requirement
• Require an exit button (Request to Exit / REX) on the secure side to allow egress without a credential

Wiring a maglock:

• 12V DC from power supply / controller to the maglock (typically 2-core cable)
• Relay output from the access controller breaks the power to release the lock on valid credential

Electric Strikes

• Fit in the door frame in place of the mechanical strike
• Fail-safe or fail-secure versions available
• Power requirement: 12V or 24V DC, typically 300–500mA
• Suited to timber doors with standard mortice latch/lock

Exit Buttons (Request to Exit)

Required on any access-controlled door to allow occupants to exit freely without a credential:

• Press-to-exit button mounted on the internal side of the door
• Wired to the access controller's REX input — triggers door release without logging an access event
• Use timed release (3–5 seconds) to allow time to open the door and pass through

Standalone Access Control (Single Door)

For a single door where audit trails and remote management are not required:

Typical system:

• Combined keypad and RFID reader (e.g. Paxton Net2 Nano, Videx, BPT)
• Power supply (12V DC, 1–2A)
• Electric lock (maglock or strike)
• Exit button

Wiring:

Power supply (12V)
├── To access controller board
├── To electric lock (via relay output on controller)
└── Common earth

Access controller
├── Reader (4-wire: +12V, GND, Data0, Data1)
├── REX input (exit button)
└── Lock relay output → lock

Installation steps:

1. Mount the access controller / power supply in a secure location (inside the protected area)
2. Run cable to the reader/keypad at the door frame (typically 4-core cable for Wiegand readers)
3. Run cable to the electric lock (typically 2-core, sized for the lock's current draw)
4. Run cable to the REX button (typically 2-core)
5. Connect and programme the controller (set PIN codes, add fobs)
6. Test: present each credential, confirm lock releases; press REX, confirm release

Networked Access Control (Multi-Door)

For larger sites with multiple doors, audit requirements, or time-zone access:

Common systems: Paxton Net2, Salto, Abloy, Honeywell Pro-Watch.

Architecture:

• Central controller / server connected to the site LAN
• Door controllers (one per door or one per two doors) connected over Cat6
• Readers at each door connected to their door controller
• Management software on a PC — programmes users, access levels, time zones; produces access reports

Key wiring points:

• Controller to server: Cat6 network cable (TCP/IP)
• Reader to door controller: 4-core Wiegand (or RS-485 OSDP)
• Lock to door controller: 2-core (12V or 24V from the controller's relay/lock output)
• Door sensor: 2-core to the door controller's monitor input — detects if door is held open

Power Supplies

Access control power supplies must provide:

• Continuous 12V or 24V DC for the locks and electronics
• Battery backup — typically 7Ah or 17Ah sealed lead-acid. The system must continue operating during a mains power failure.
• Sufficient current for all locks on the supply (each maglock typically draws 500mA–1A)

Size the power supply: Add up the current draw of all locks. Allow 20% headroom.

Testing

After installation:

• Each valid credential grants access (fob, card, PIN)
• Invalid credentials are rejected
• REX button releases door correctly
• Door contact (if fitted) registers door-open state correctly
• Door locks automatically after the programmed release time
• Battery backup: disconnect mains and confirm system continues to operate
• Audit trail: access events are logged correctly in the software (networked systems)

Common Issues

Related Documents

• Getting Started — Door Entry & Access Control
• IP Video Door Entry Systems