metalpushbutton switches Dedicated ground wire
Push button switch is normally closed, often open two pairs of points. PLC input in accordance with the requirements to use these two pairs of points. For the use of normally closed point, the PLC input according to the different models have separate input, there are common points. Follow the instructions to connect. The common electrode is connected to a terminal, and the input point of the PLC is connected to another terminal, that is, the I-side (one of the input points of the plc) of the PLC is connected with the movable contact, and the other end is connected to the 24V + of the PLC.
Metal button switch In general, a button always has a pair of moving contacts and a moving contact, before the application of multimeter block to distinguish the corresponding contacts, but also have two pairs of contacts and with Light, wiring should pay attention.
The push buttons and button boxes of the metal pushbutton switch buttons must be metal and try to connect them to the device's common ground bus. There must be a dedicated ground wire for the hanging button, and no metal pipe must be used as the ground wire.
Second, the PLC module internal switch AO / DO output capacity is very small, can not directly drive the external switch (contactor) action, through a small electromagnetic relay (usually said that the intermediate relay) is a switch transfer control process , That is, the total output of the PLC module in the middle of the relay -> contactor metal button switch in the application of the time there are many aspects of the need to pay attention, because the metal button switch is also involved in the security aspects of the content is more, And for this application we also need to pay special attention to the place is the use of metal button switch when it is not the hands of water also to contact the metal button switch this situation is very dangerous.
What about the role of metal button switches in the application of the time and what aspects of the content? We can from these aspects to understand it.
The first is the metal button switch on the angle of consistency can be done well; then there is no turn on the phenomenon of flash occurs when the user can be assured; that is for the environmental aspects, as well as transport The process, as well as in the use of which will not cause pollution, which is a very good point.