Security Fog + Alarm / Burglar System Integration

Adding security fog to any commercial alarm panel is a 30-minute wiring job: the panel’s programmable output triggers the fog system’s IN+/IN- terminals on verified two-sensor activation. The fog rides on top of your existing sensors and your existing monitoring contract — no parallel system, no second monitoring fee.

How fog connects to an alarm

Any commercial alarm panel made in the last 20 years has at least one programmable output that closes on alarm. That’s all the fog unit needs. Universal pattern:

1. Sensor (door contact, glass-break, PIR, shock) trips
2. Panel verifies via two-sensor activation
3. Panel closes programmable output (Form-C relay output, open-collector pulse, or supervised output)
4. Output wires to fog unit’s IN+/IN- dry-contact terminals
5. Fog discharges 5-10 seconds after panel output closes
6. Panel continues sending the alarm to central station independently

The fog system is panel-agnostic by design — if your panel can close a relay, it can fire the fog.

Trigger logic & zones

Recommended configuration:

• Two-sensor verification: require at least two independent sensors to trip within a short window before firing fog. Standard pairings: glass-break + interior PIR, or door contact + showcase shock sensor.
• Per-zone fog scoping: different sensor zones can fire different fog units (front-of-house vs back-of-house vs vault). Larger panels (Bosch B-series, Honeywell Vista 128, DSC PowerSeries Pro) support up to 16 independent fog zones natively.
• Daytime panic trigger: a hardware panic switch wired in parallel with the alarm output gives staff manual fog control during armed encounters.
• Tamper zone: the fog unit’s housing tamper switch routes to a dedicated zone on the panel so attempted defeat of the fog unit triggers fog deployment.

Preventing false deploys

False discharges are the most common installer mistake. Five rules to prevent them:

1. Never trigger fog on single-sensor activation. Always require two-sensor verification.
2. Don’t wire interior PIRs as the only trigger. Movement during accidental late-hour staff visits would false-fire.
3. Test the verification logic monthly in test-mode — confirm the panel doesn’t pass to the fog output on single trips.
4. Use supervised outputs where the panel supports them — the panel will fault if the fog trigger wire is cut, preventing silent defeat.
5. Document the trigger logic for your insurance broker — most carriers want to confirm two-sensor verification before granting the premium discount.

Install considerations by panel brand

• Bosch B-series: programmable output configured via RPS programming software; supports per-zone fog scoping natively.
• Honeywell Vista (15P, 20P, 128BPT, etc.): field-configured output via *80 or *93 menu; one auxiliary output drives most retail-size fog deployments.
• DSC PowerSeries Pro: programmable terminal configured via DLS5 software or Tlink RX; supports up to 32 independent fog zones on larger panel models.
• Ajax Hub Hybrid: see our dedicated Ajax integration guide.
• UTC GE Concord 4 / Concord Express: legacy installs supported via supplemental relay accessory.
• Generic / older panels: if your panel lacks a programmable output, install a piggyback relay accessory that monitors the siren output and fires fog in parallel.

Warehouse zone integration

For warehouse and DC deployments, the multi-zone integration matters. See our warehouse fog deployment guide for the per-zone trigger pattern that handles dock-area + high-value cage + office independently from a single panel.

See also: Ajax-specific integration · vs alarms · installation · warehouses.

Frequently asked questions

Does my panel need a special module to fire fog?
No. Any commercial alarm panel made in the last 20 years has at least one programmable output that closes on alarm. That's all the fog unit needs. Specialty modules are not required for any major-brand panel.

Can I trigger fog without monitored central-station alarm?
Yes — the fog fires from the panel directly, not from central station. The monitoring contract is independent. If you have an unmonitored panel, fog still fires on local verification.

How do I prevent false fog deployments?
Always require two-sensor verification (not single-sensor activation). This eliminates the vast majority of false discharges in documented operator data.

Will the alarm signal still reach my central station after fog fires?
Yes. The central-station signaling happens in parallel with the fog discharge — both are downstream of the panel verification event. Fog deployment doesn't interfere with alarm transmission.

What if my panel is too old to have a programmable output?
Install a piggyback relay accessory that monitors the siren or strobe output and fires fog in parallel. This works on any panel ever made and adds approximately $40-$80 to the install cost.