1, different ways of use: the active is generally connected to the relay coil, and an external 24V power supply is needed to receive current or voltage signals. When the non-coding detector of the general manufacturer gives an alarm, it outputs a current signal, which is used to connect the interface module addressed by the manufacturer and input it into the system; Passivity is generally connected to the normally open point or normally closed point of the relay, which gives an external opening and closing signal, receives a passive contact signal, and is connected to the system through the input of this signal. The universal input module can be used to receive the alarm and feedback signals of water flow indicators, pressure switches, signal valves and other equipment.
2. The principle is different: the power output module needs to cooperate with the relay to convert the output power signal into an on-off signal; Passive input and output module, normally open point input module, after the module is started, the output end changes from normally open state to normally closed state; Normally open and normally closed I/O module, there are two kinds of switch state changes at the output end, that is, normally open point becomes normally closed point, and normally closed point becomes normally open point.
3. Different safety: passive contacts are safer for fire fighting system, and active contacts are directly controlled by 24V power supply provided by fire fighting equipment. At this time, if the 24V line accidentally touches the 220V power supply, the circuit will be burned immediately.