Letting a camera open the gate.

Plenty of IP cameras include physical input and output terminals. An output is a switch the camera can close on command, and that is all a gate controller, a door strike or a relay needs. VISEC drives those outputs through ONVIF and on Axis cameras, so a recognised plate or a scanned QR code can operate whatever the terminals are wired to.

• A camera with output terminalsNot all have them. Professional models usually do — Axis, Bosch and Milesight commonly include alarm I/O. Check the specification before buying for this purpose.
• Something to switchA gate motor, barrier or door controller with a dry-contact trigger input. Most already have one, because that is what a card reader or keypad uses.
• An electrician, for the mains sideLow-voltage trigger wiring is straightforward. Anything touching mains or an existing access system should be done by someone qualified.
• A camera placed to actually readThe trigger is the easy half. Getting a reliable read is the part that needs the right lens, angle and infrared.

Keep the plates you want admitted in the local plate database, then add an action on a match that drives the camera output. QR codes work the same way, which is useful for visitors and deliveries — a code on a phone, no card to issue and nothing to get back. Both are configured per camera in the LPR and QR properties; the access control page covers what the module does.

• What happens when it does not readMud, snow, a missing plate or a visitor. There must be an intercom, a keypad or a person. Never leave recognition as the only way in.
• What happens in a power cutAsk how the gate is meant to behave, and make sure it does that.
• Log everything, including refusalsThe value is partly the record. A vehicle with no readable plate can raise its own alert.
• Plates are not secretsA plate is visible to anyone and can be copied. For a site where that matters, treat it as convenience and pair it with something else.