How it works
Commercial cooking equipment under a hood that has a fire suppression system is generally required to lose power when the suppression system discharges. This is commonly done with a shunt-trip breaker: a breaker with an added coil that trips it open when it receives a signal from the suppression system.
Related electrical connections
When a suppression system activates, ventilation equipment often needs to respond in a specific way. Depending on the design, make-up air units may need to shut down, exhaust fans may need to keep running, and gas valve solenoids may need to close. These sequences depend on the system design, the manufacturer’s instructions and your local authority having jurisdiction.
What we do
- Install or replace shunt-trip breakers and subpanels serving cooking equipment
- Run and terminate control wiring between the suppression system’s switch and the breakers or contactors
- Connect exhaust fans and make-up air units to match the required sequence
- Troubleshoot equipment that doesn’t shut off, or breakers that trip unexpectedly
- Coordinate with your fire protection contractor and hood installer during testing
What we do and don’t do: We are an electrical contractor. We do not install or service the fire suppression system itself, including the tank, piping, nozzles or fusible links. Those are handled by a licensed fire protection contractor, and we coordinate with them on the electrical connections and testing.
Common problems
- Shunt-trip breakers that trip during normal use because of damaged or miswired control wiring
- Equipment that fails to de-energize during a suppression system test
- Breaker and panel mismatches when equipment is added or relocated
- Damaged or grease-fouled switches and wiring
Frequently asked questions
Why can’t a regular breaker be used?
A regular breaker only trips on overload or a short circuit. A shunt-trip breaker can also be tripped remotely by a signal from the fire suppression system, which is how equipment is shut off when the system discharges.
Can one signal shut down multiple appliances?
Often, yes. Depending on the layout, cooking circuits can be grouped on a shunt-trip main or shunt-trip devices can be wired to the same control signal. We’ll review your kitchen’s layout.
What requirements apply to my kitchen?
Requirements depend on your equipment, hood system and local authority. Your hood or fire protection contractor and the local fire official are the right sources for system requirements. We handle the electrical side and coordinate with them.