Hi i have getting a lot of noise on analogue input…
Where the transducer cable is running next to the 440v supply for 500 meter…
Electrical noise in analog signals can be a significant problem, particularly when you’re dealing with long cable runs next to high voltage lines.
Noise in PLC
Here are some potential ways to reduce this noise:
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Shielding: Use shielded cables to reduce electromagnetic interference. The shield acts as a protective barrier that prevents noise from reaching the signal conductors. Ensure that the shield is properly grounded at one end.
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Twisted Pair Cables: These are effective in reducing the effect of electromagnetic interference (EMI). In these cables, the pairs are twisted which can help to cancel out any noise that is induced in the cable.
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Use of Filters: Analog filters can be used to remove noise from the system. These filters should be chosen based on the frequency of the noise.
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Physical Separation: If possible, try to physically separate your transducer cable from the high-voltage supply. The further they are apart, the less interference you will have.
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Differential Signaling: This is a method of transmitting information electrically by using two complementary signals sent on two separate wires. The receiver looks at the difference between these two signals. Since any interference would likely affect both wires equally, the differential method can help to reject this noise.
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Use of Opto-Isolators or Signal Conditioners: These devices can isolate one part of a circuit from another, so that only the desired signal can pass through.
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Proper Grounding and Bonding: Ensure that your system is properly grounded and bonded according to local codes and good engineering practices. This can significantly reduce noise in the system.