摘要:
A safety device for an industrial boiler (CHA) including relays (REn) which are connected to form an electromechanical safety chain (CH1). Each relay (REn) is mounted on a printed circuit board (CIA, CIB, CIC, CIP). As a result of the arrangement, the relays can be mounted in a compact box that may be sealed so that it is impossible for an operator to access a relay in order to block it.
摘要:
A safety device for an industrial boiler (CHA) including electromechanical relays (REn, RS), which are connected in series in order to form an electromechanical safety chain (CH1), and at least one shunt relay (RTn) which is normally open and mounted in parallel to one of the electromechanical relays (REN). The shunt relay is controlled by an automaton (AP1) so that it is closed during a time delay. The shunt relay (RTn) is provided with a contact that is connected to an electronic circuit (CEn) and said electronic circuit (CEn) opens an electromechanical relay (RS) which is mounted in series in the safety chain when the shunt relay (RTn) is closed for longer than the time delay. Given the arrangement, in the event of an automaton failure, the time delay is ensured by the electronic circuit so that a satisfactory level of safety is guaranteed in relation to the installation.