UniFi Fail-Secure Bolt Lock

The UniFi Fail-Secure Bolt Lock is an electric drop bolt lock built for UniFi Access. It stays locked when power is lost and releases only when the Access Hub energises it, so restricted rooms remain protected during an outage. It recess-mounts into single wooden or metal door frames, includes a built-in door position sensor, and runs on 12V DC directly from the hub's powered relay.

Security that holds when the power doesn't

Fail-secure means exactly that. Without power, the bolt stays in the locked position, and the UACC-Lock-Bolt-Secure only unlocks when the UniFi Access Hub applies current. A power cut, a tripped breaker or a severed cable leaves the door secured rather than open. Ubiquiti positions its fail-secure locks for restricted areas such as data storage rooms, where maintaining security through an outage matters more than hands-free egress. For emergency exits and general building entry and exit doors, Ubiquiti recommends the fail-safe alternative, the UACC-Lock-Bolt-Safe.

Designed for UniFi Access

Ubiquiti designed this lock for NO/COM/NC relay wiring with the UniFi Access Hub. Connect the red 12V/NO and black COM leads to the hub's powered 12V-1A relay terminal. At rest, the relay is open, no current flows and the bolt stays locked. When UniFi Access triggers an unlock event, the relay closes, current flows through the lock and the bolt releases. A blue 12V/NC lead is also provided. Because the lock runs on 12V DC at a maximum of 900 mA, it sits comfortably within the hub's 12V-1A output, with no separate power supply required.

Know whether the door is actually closed

An embedded door position sensor (DPS) gives your access control system a dry-contact signal for door state: the DPS/+ and DPS/- leads read as an open circuit when the door is open and as a short when it is closed. The contact is rated to a maximum of 30V DC at 0.5A. That lets you distinguish a door that is merely unlocked from one that has been left standing open.

Clean, recessed installation on wooden or metal doors

The lock is a door frame recess mount for single wooden or metal doors. The lock body measures 132 × 30 × 42 mm (5.2 × 1.2 × 1.7") and weighs 350 g (12.3 oz), with an aluminium alloy enclosure. It is supplied with an aluminium alloy door frame plate (82 × 32 × 3 mm) and door plate (204 × 33 × 3 mm). Ubiquiti publishes an online installation guide for the UACC-Lock-Bolt-Secure covering first-time setup and wiring to the Access Hub.

Status at a glance

A built-in LED shows the lock state from the frame: red for locked, green for unlocked and power present.

Rated for real-world conditions

The lock operates from -10 to 60 °C (14 to 140 °F) at 5 to 90% non-condensing humidity, and can be stored from -20 to 70 °C (-4 to 158 °F). It is NDAA compliant and carries FCC, IC and CE certifications.

Key features

• Fail-secure by design — stays locked through power loss; unlocks only when energised by the UniFi Access Hub.
• Made for UniFi Access — designed for NO/COM/NC relay wiring; powered directly from the hub's 12V-1A relay, no extra PSU.
• Embedded door position sensor — dry-contact DPS reports door open/closed (max 30V DC, 0.5A).
• Recess-mounted, low profile — fits single wooden or metal door frames; aluminium alloy lock body.
• LED status indicator — red = locked, green = unlocked and powered.
• 12V DC ±10%, max 900 mA — matched to the Access Hub's powered relay output.
• Wide operating range — -10 to 60 °C, 5–90% RH non-condensing.
• NDAA compliant; FCC, IC and CE certified.
• Fail-safe sibling available — UACC-Lock-Bolt-Safe for egress and entry/exit doors.

Compatibility and what you'll need

• UniFi Access Hub (Access Control Hub) — the lock is designed for the hub's NO/COM/NC relay terminals. Fail-secure locks connect to the NO and COM terminals of the hub's powered 12V-1A relay.
• Lock cabling — Ubiquiti recommends shielded 22 or 18 AWG cable between the hub and lock for best results, and sells a Door Lock Relay Cable (UACC-Cable-DoorLockRelay) for this purpose.
• Door — a single wooden or metal door with a frame that can accept a recess-mounted lock body.
• Need fail-safe instead? For emergency exits and building entry/exit doors, choose the UACC-Lock-Bolt-Safe, which unlocks automatically on power loss to ensure safe egress.