Wiring of proximity switch
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Experts, the DI input of the PLC I’m using is a pair of contact switches; 24V power supply comes in through these switches, and feedback is sent back via the contacts. Now I want to replace this switch with a two-wire proximity switch. Can I just connect the wires directly? No modifications are needed, right? Please help.
It depends on the way your PLC processes digital input signals. In most cases, connections to the PLC are made through optocouplers for isolation; this might be the cause of problems with two-wire proximity switches, as for such switches, 2.1 mA indicates a closed state. So, based on your judgment, can your PLC recognize these two current signals? There are also two-wire proximity switches that have requirements regarding the supply voltage; it is important to ensure that this meets the voltage requirements of your PLC.
Is the supply voltage always DC24V? Digital input of Siemens PLC400. Can it be replaced directly? So you mean that adding a relay transfer will do? But I don’t want to add it anymore. Do you think it’ll work?
Hello everyone. Our factory produces inductive proximity switches that can withstand temperatures up to 150 degrees Celsius. These switches come with a one-year warranty. They are also NAMUR-certified intrinsically safe explosion-proof proximity switches, operating at a supply voltage of 8.2V; the output current is ≤1mA when in operation and ≥3mA when not in operation. Their performance is stable, making them suitable as alternatives to similar imported products from brands such as Pilz and Turck.
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It depends on whether the PLC accepts NAMUR signals; it’s possible for Siemens devices, as they both follow German standards, but this isn’t necessarily the case for other devices
It depends on the type of two-wire proximity switch you have; some require a specific operating voltage, such as the 8 V DC version from P+F, in which case you need to add an appropriate safety barrier behind the panel.