Electric Strikes and Electrified Locks

An electric strike is a frame-mounted plate that releases the latch when it gets a small electrical signal. The lock on the door stays where it is. A keypad, card reader or buzzer sends the signal, the strike lets go for a few seconds and the door opens. We handle electric strike installation in Phoenix and across the Valley, and where the hardware allows it we fit the strike to the lock you already have.

A strike is one of three common ways to unlock a door by signal. The others are electrified locks and magnetic locks. They behave differently when the power goes out or the fire alarm sounds, and that difference is a life-safety question, not a matter of taste. Call (602) 301-5243 Monday to Friday, 8:30am to 6pm, and we will talk through your door.

Electric strike, electrified lock or magnetic lock

Fail-safe and fail-secure in plain words

These terms describe what the door does when power is removed, from the secure side, which is usually the outside.

Neither mode has to trap anyone inside. On most strikes and electrified locks, the lever or exit device on the inside still lets people out whatever the power does. Magnetic locks and some double-cylinder institutional locks are the exceptions, which is why the code asks for added release devices on them. Some strikes can be set either way. Others are built one way only.

Why it matters

• Fire-rated doors. A fire door has to latch positively when it closes, and a fail-safe strike does not hold the latch that way. So a strike on a fire-rated door is normally a fail-secure one. Electrified locks are treated differently from strikes, so ask before you assume. The door’s label and the authority having jurisdiction (AHJ) decide what is allowed.
• Stairwell doors. Fail-safe trim is often chosen where people need to get back in from a stair when power fails or the alarm sounds. Whether re-entry is required depends on the building and the code edition.
• Security. Fail-secure hardware is the more common choice, because the door stays locked in an outage.

Matching a strike to the lock

A strike has to match the lock’s latch type, the backset, the frame and the door. A mortise latch, a cylindrical latch and a deadlatch each need a strike made for them, and a mortise deadbolt needs one that handles the deadbolt throw. We check what is on the door before we recommend anything.

Models differ. Adams Rite lists electric strikes for aluminum and steel doors, including a 7100 series that can operate fail-safe or fail-secure. Other strikes are built fail-secure only, and some fit only certain lock types. Check the exact model before you order, because a strike that does not match the latch will not work.

One limit worth knowing: Adams Rite says its MS+1890 combination lock cannot be used with electric strikes, and electrified trim is not offered for it. On a storefront with that lock, the lock has to change before the door can be wired. See storefront door locks and glass door locks for how those doors are built.

A word on magnetic locks

A magnetic lock holds the door shut with power. It has no lever or latch that people can work by hand, so it needs more around it than a lock does. Codes ask for added release devices so people can always leave. Commonly that means a request-to-exit sensor, a push button that cuts power on its own, and a release tied to the fire alarm. Without those pieces, a person inside has no dependable way out. The fire marshal decides what a given door needs, and we will tell you plainly if a magnetic lock is the wrong choice for yours.

Power and power supplies

Many strikes and electrified locks run on low-voltage power, commonly 12 or 24 volts, and some models accept either. Current draw varies by model, and the supply has to be sized for the total draw of everything it feeds. Read the voltage, the current and whether the device wants AC or DC from the data sheet for the exact model.

• Wire gauge follows the run length. Long runs lose voltage, so manufacturers publish a wire gauge by distance for each device. Use the table in the installation instructions for the exact model, not a rule of thumb.
• Battery backup shapes outage behavior. A supply with backup keeps the door in its normal state until the battery runs down. After that, a fail-safe door unlocks and a fail-secure door stays locked.
• Fire alarm input. Many access control power supplies have a fire alarm contact that cuts power to the locks on alarm.

Request to exit, key override and fire alarm

Request to exit

A request-to-exit device, or REX, is a switch or motion sensor on the inside of the door. It tells the system that someone is leaving on purpose, so the door does not report as forced. On a magnetic lock or a door released by a sensor, the exit release is part of the life-safety chain, not an accessory.

Key override

Many electrified locks have a key override so you can get in when the power or the controller fails. With a strike on a mechanical lock, the key on that lock still works. A magnetic lock has no key at all. That puts key control back on the table, so rekeying and master key systems still matter on an electrified door.

Fire alarm interface

Where a building has a fire alarm system, electrically locked doors on exit paths are commonly required to unlock when it activates. That is usually done with a relay contact from the fire alarm panel that removes power from the lock supply. Inspectors may hold up a fire system when electric locks are not tied in, whichever contractor installed each piece. The wiring involves the fire alarm company, and the fire marshal has the final word.

What we do, and what an electrician or alarm contractor does

We tell you at the start which parts of your job need another trade. A strike only secures a door that closes and latches, so a weak or misadjusted door closer can leave the door unsecured.

The Arizona contractor rules, in general

Arizona does not license locksmiths. It does license contractors, and the Registrar of Contractors (ROC) lists classifications for electrical work and for low-voltage work such as alarm and signaling systems.

Whether a given wiring job needs a contractor license depends on the work, its value and whether a permit is required. Check the rules for your project with the Registrar of Contractors at roc.az.gov, and if your job includes wiring beyond the door, ask the contractor doing that part which license covers it. This is general information, not legal advice.

How an installation goes

1. Decide what the door must doWho gets in, when, and what happens in a power failure and on a fire alarm. If the door is fire-rated, that comes first.
2. Match the strike to the lockLatch type, backset, frame material and handing. Confirm fail-safe or fail-secure and the voltage.
3. Plan the powerSupply size, wire gauge for the run, battery backup, and the fire alarm contact if one is needed.
4. Prepare the frameCut the opening and mount the strike without exceeding what a fire label allows.
5. Connect and testOnce the strike, the request-to-exit and the keypad or reader are connected, test with power on, with power off, with the key, and, where it is tied in, on a fire alarm signal. Confirm the door latches fully and people can still leave freely.

Simple jobs are priced on the phone. For access control or several doors, we look at the doors first and agree on the price before work starts. Start on the commercial quote page. To see how strikes fit into a whole system, read about access control systems. Panic bars can be electrified too, with electric latch retraction or electrified outside trim. See panic bars and exit devices. If a strike or reader stops working and you are locked out after hours, call anyway. If we are free, we will come.

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