Access control and fire alarm systems have to work together, not around each other: when the fire panel trips, every card-reader door on the life-safety egress path needs to unlock automatically, or you have a code violation and a liability problem. Instead of relying on staff to prop doors during an alarm, wire the access control panel directly to the fire alarm control panel's relay output so doors release the instant smoke or heat is detected.

This guide covers the relay wiring, panel programming, and lock hardware that make that handoff work, plus the fail-safe requirements most inspectors check first.

Why this matters

A fire alarm system that doesn't talk to your access control panel leaves locked doors locked during an evacuation. That's a life-safety failure, and it's one of the first things a fire marshal checks during inspection. The fix is a relay interface, not a software patch — the fire alarm control panel needs a dedicated output wired straight into the access control panel's supervised input.

Most small and mid-sized businesses in New Jersey run this integration wrong the first time: they wire the relay but leave the door hardware on fail-secure strikes, which stay locked on power loss. DBSI walks clients through both the wiring and the hardware swap because one without the other still fails inspection in 2026.

Before you start

• Confirm your fire alarm panel has a spare relay output. Most commercial panels ship with at least one programmable relay, but older panels may already have every output committed to strobes and horns.
• Check your door hardware type before touching wiring. If your egress doors use fail-secure electric strikes, the relay connection alone won't release them — you need fail-safe hardware on any door in the path of egress.
• The gotcha: access control panels default to "locked on power loss" for security doors, which is the opposite of what fire code requires on egress paths. Reprogram this setting before wiring the relay, or the interface will look correct on a bench test and still fail a live drill.

Set up the fire alarm relay output

1. Open the fire alarm control panel and locate an available auxiliary relay output (labeled REL1, REL2, or similar depending on panel brand).
2. Program the relay to activate on general alarm, not just a specific zone — a fire in one wing still needs to unlock doors building-wide unless your fire marshal has approved a zoned egress plan.
3. Set the relay for normally closed, opens on alarm — this is the fail-safe configuration that drops power to the lock circuit when the alarm trips.
4. Confirm the relay contact rating matches your access control panel's input specs before wiring. Mismatched voltage here is the most common reason installers damage a relay board on the first test.

Expected result: the relay shows continuity on the panel's diagnostic screen and drops to open when you trigger a manual alarm test.

Configure the access control panel input

1. Wire the fire alarm relay's dry contacts into the access control panel's fire alarm input, or into a dedicated supervised input if no labeled fire input exists.
2. In the access control software, create a global unlock rule tied to that input — this rule must override every existing door schedule, including holiday lockdowns and after-hours restrictions.
3. Set the rule priority above all other access rules. If two rules conflict, the fire alarm unlock must always win.
4. Save and push the configuration to every door controller on the egress path, not just the doors nearest the panel.

Expected result: triggering the fire alarm input in the software immediately shows every configured door as unlocked in the access control dashboard, with no manual step required.

Fail-safe vs. fail-secure hardware

Before wiring goes live, confirm every door on the egress path uses hardware that unlocks on power loss. This is where most integrations fail inspection, not the relay wiring.

Fail-safe hardware on egress doors is not optional under fire code — if your building has fail-secure strikes on any door in the path of egress, swap them before the interface goes live. The tradeoff is honest: fail-safe maglocks draw continuous current and release during any power outage, so a door that must stay secured around the clock is the wrong candidate for the egress path in the first place.

Second variant: lock down instead of unlock on intrusion alarm

A related workflow runs the opposite direction. Some businesses want doors to lock automatically when the security alarm arms after hours. That's a separate relay and a separate rule set — DBSI's guide on how to automatically lock doors when your alarm system arms covers the wiring for that direction. Don't combine the two rule sets on the same relay input; fire-alarm-triggered unlock and intrusion-triggered lock need independent inputs so one system's logic never overrides the other's during a real event.

Troubleshooting

• Doors don't unlock on alarm test, but the relay shows correct voltage. The access control panel's global unlock rule is sitting below a scheduled lockdown rule — check rule order, not the wiring.
• Only some doors release. The configuration push didn't reach every door controller. Re-push the rule to each controller individually and confirm firmware versions match.
• Doors unlock, then relock within seconds. The fire alarm relay is set to a timed pulse instead of a maintained contact. Reprogram it to hold the contact open for the duration of the alarm state.
• Maglocks sag open during a long drill. Fail-safe maglocks draw continuous current to stay locked, so a weak backup battery drops them early. Replace aging batteries as part of the annual fire alarm inspection.
• False alarms trigger a full building unlock. That's expected behavior, not a bug — code requires it. If false alarms are frequent, the fix is fire alarm sensor maintenance, never disabling the access control interface.

Customize your workflow

Once the fire alarm interface is live in 2026, most businesses extend the same logic to related events. Pair the fire alarm relay with a photo log so security staff can see who was in the building at the moment doors released — automatically log a photo when access control grants entry covers that setup.

If you're installing access control for the first time rather than retrofitting an existing panel, start with how to install access control in an existing office before wiring the fire alarm interface, since door hardware selection happens at that stage and dictates everything downstream.

For buildings with a server room or other high-value space near the same egress path, review how to secure a server room with access control and cameras. Those rooms often need a documented exception to the global unlock rule, and getting that exception wrong is its own inspection flag.

FAQ

One last thing

Most failed inspections trace back to one detail: the access control panel's global unlock rule gets buried under a holiday lockdown schedule nobody remembers to check. Retest the fire alarm interface after every schedule change to the access control system, not just after installation — a holiday rule added in November 2026 can silently outrank the fire alarm override that tested clean in January 2026.

Related guides

• How to choose an access control system for your business
• How to onboard employees with new access control credentials
• Automatically alert staff when a door is forced open