Abstract: The invention relates to the field of electrical firing mechanisms and particularly to a device for firing a primer of the type having, in particular, an electrical power supply for a circuit including a detector, a switch and an igniting device for igniting the primer, such as an electrical resistor or a striker and a device able to move the striker. The detector and switch may include a network of contacts able to open or close the circuit under the influence of a contact or a force and to close or open the circuit when the contact or the force has disappeared.