An anti-fire protection device for a starter-controller device of an electrical installation is able to be connected to an electrical power conductor and includes thermal monitoring of the electrical power conductor to detect a temperature rise of greater than a predetermined threshold. This anti-fire protection device can be fixed mechanically to the starter-controller device via at least one mechanical linking member. The thermal monitoring includes at least one temperature sensor and a cartridge including a fire extinguishing agent and at least one injection element, situated on the same face of the protection device as the temperature sensor, the cartridge being situated inside the protection device and connected to the temperature sensor, the injection element being able to inject the fire extinguishing agent towards the electrical power conductors subsequent to a detection, by the temperature sensor, of a temperature of greater than the predetermined threshold.