What problems can occur when a four-wire transmitter is wired in a two-wire configuration?
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As the title suggests, it is a 4-wire instrument powered by 24VDC. If the 24VDC supply is not connected and the two signal wires are used to connect the instrument to the PLC in 2-wire mode, what will be the status of the instrument?
Since it is a four-wire system, the power supply and the signal terminals are completely separated; if you do not connect the power supply, the instrument naturally won’t have power, the circuit will not function, and it will display abnormal readings or show no output at all. And they’ve already told you it’s a four-wire system, so why do you still connect it in this way?
The four-wire system relies on a separate power supply; without this power supply, the instrument will not function. Therefore, when a four-wire system is required, it must be installed in accordance with the specified requirements.
Wow, if you don’t connect it to the power supply, how can the instruments work? Tell me, can your computer start up without being plugged in?
If the wiring is incorrect, the transmitter will not function. In two-wire transmitters, the power supply and the signal are shared, while in four-wire transmitters they are separate. If power is connected to the signal circuit, it is possible to damage the transmitter (this is just my personal opinion; I have never done this, it’s merely a guess).
To give an inappropriate example: forcing someone to keep working without food or water. Are you going to do it or not? As mentioned above, some instruments lack strong signal isolation capabilities; supplying power to passive signals may damage the output board.
I understand everyone’s answers; I just want to know what will happen if it’s connected in this way, or who can provide the electrical schematic for the 4-wire signal output section
The circuit boards inside are all designed differently; how can it work then?
It is not displayed, or the display is inaccurate
Bro, your question really leaves me speechless
If it uses a two-wire system without separate power supply, it cannot be used