SEP-1 / SEP-1A thermal actuator

The SEP thermal actuator is used in self-contained fire suppression systems to trigger aerosol fire suppression generators. It generates or transmits an electrical impulse when the ambient temperature exceeds the activation temperature of the sprinkler thermal element fitted to the actuator.

The device is intended for continuous operation in heated and unheated enclosed rooms. Versions are SEP-1 and SEP-1A. Depending on project requirements, the SEP-1 version may be supplied without a battery.

Technical data

• Models: SEP-1 / SEP-1A
• Height: 110 mm
• Diameter: 50 mm
• Actuator assembly mass: 0.2 ± 0.05 kg
• Control area for one device in a room up to 10 m high: maximum 18 m²
• SEP-1A nominal voltage: 3 V
• SEP-1A nominal capacity: 0.85 Ah
• SEP-1A operating temperature range: −20 °C to +50 °C

Construction and operation

The actuator consists of a housing with a contact group, base and cover containing the sprinkler. The sprinkler valve holds the contacts open. At the rated activation temperature, the glass bulb breaks, the spring moves the valve and the electrical contacts close. Voltage then appears at the actuator outputs and an electrical impulse is sent to the aerosol generator initiator.

Installation and use

Before installation, inspect the sprinkler bulb, output contacts and markings. Check that the sprinkler activation temperature matches the label, check the voltage at the actuator terminals, and check the inspection mark and manufacturing date.

Fix the actuator to the ceiling or another structure in the protected room. Where several actuators are installed, their positions and wiring arrangement must be defined by the project.

Protect the device from impact during operation. Do not close the contacts manually, as this may discharge the power source.