Electronic Drop Bolts

Electronic Drop Bolts For Reliable Access Control

An electronic drop bolt is one of the most straightforward ways to add electric locking to a door within an access control system. Rather than sitting inside the door frame like an electric strike, a drop bolt mounts to the door and header (or door and floor), driving a solid steel pin into a matching receiver when the system commands it locked. That makes it a common choice for glass doors, narrow-stile aluminium doors, double doors, and any application where a mortice lock body isn't practical. Keeler Hardware stocks electronic drop bolts in both fail safe and fail secure configurations, suited to commercial fit-outs, office entries, plant rooms and specialised door types that standard hardware can't handle.

Choosing The Right Drop Bolt For Your Door

Specifying a drop bolt isn't just about picking a size, the locking mode and mounting method both need to match the door, the frame, and the level of security or life-safety compliance required for the space.

What's The Difference Between Fail Safe And Fail Secure?

This is the single most important decision when specifying an electric drop bolt, and it's also the easiest one to get wrong.

• Fail safe (unlocks on power loss): the bolt retracts if power is cut, so the door is free to open. This is generally required on paths of egress and fire-affected doors, where occupants must be able to exit during a power failure.
• Fail secure (locks on power loss): the bolt stays extended if power is cut, keeping the door locked. This suits high-security areas like server rooms, comms cupboards or stock rooms, where the priority is keeping the space secured even during an outage.

Get this wrong and you either lock people into a building during an emergency, or leave a secure area accessible the moment power drops, so it's worth confirming with your access control installer or fire engineer before ordering.

Can Electronic Drop Bolts Be Used On Glass Doors?

Yes. Surface-mounted electronic drop bolts are one of the few electric locking options that work cleanly on frameless or semi-frameless glass doors, since there's no door leaf to rebate a strike or mortice lock into. They're also a common pairing with a magnetic lock on double glass doors, giving redundancy across both leaves.

How Do Drop Bolts Integrate With An Access Control System?

A drop bolt is a locking device, not a decision-maker, it needs to be wired into a controller, reader, or electric key switch that tells it when to lock and unlock. Most commercial installs also pair a drop bolt with request-to-exit hardware and a monitored door position switch, so the building management system always knows the real-time status of the door. If you're speccing a full system rather than a single door, our range of smart locks and digital locks covers standalone options where a full access control panel isn't required.

Frequently Asked Questions

Are electronic drop bolts suitable for fire doors?

 Only in fail safe configuration, and only where it forms part of a compliant, certified door hardware set for that fire door, always confirm with your certifier or fire engineer, as requirements vary by building class.

Do I need a separate power supply for a drop bolt?

 Yes. Drop bolts run on low-voltage DC power (commonly 12V or 24V) supplied through an access control power supply, not directly off mains power.

Can a drop bolt be used as the only lock on a door?

 It can, but on higher-traffic or higher-security doors it's common to pair a drop bolt with an electric mortice lock or electric strike for mechanical backup in case of a power or system fault.

What's the difference between a drop bolt and a magnetic lock?

 A drop bolt physically extends a steel pin into a receiver and offers positive mechanical locking; a magnetic lock holds the door via electromagnetic force. Drop bolts are generally preferred where higher holding force or a mechanical fail-secure option is needed.