Post History
Why are CY capacitors on the source side, and not on the load side? You may not be grasping what the image shows. The left-side port connects to the AC power-line. It supplies power to the rig...
Answer
#6: Post edited
by
Andy aka
·
2024-05-07T09:50:22Z (8 months ago)
- > _Why are CY capacitors on the source side, and not on the load side?_
I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. That port naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential "victim" of that interference).The Y capacitors on the right equalize (on both lines) the interference that the switch mode power supply naturally generates. In doing that, they naturally improve the performance of the CMC. In other words, if both lines on the right are made to have the same interfering voltage (with respect to earth) then the CMC does a much better job of reducing the interference coupled back to the port on the left.
- > _Why are CY capacitors on the source side, and not on the load side?_
- You may not be grasping what the image shows. The left-side port connects to the AC power-line. It supplies power to the right-side port via the filter. The right-side port (called power supply) is in fact a switch mode supply (SMPS) like a flyback converter.
- What may be confusing you is that the right-side port is labelled "source" and that the left-side port is labelled "load". Those terms are used because the image is showing how interference (generated by the SMPS) can be inflicted back on to the AC power line.
- Hence, the source of interference is the SMPS (the aggressor) and, the left-side port is regarded as a potential "victim" of that interference.
- The Y capacitors attempt to equalize both lines on the right-side port to the same level of interference with respect to earth/ground. This then means that the CMC is dealing with mainly common-mode interference from the SMPS.
- In other words, if both lines on the right are made to have the same interfering voltage (with respect to earth) then the CMC does a much better job of reducing the interference coupled back to the port on the left.
#5: Post edited
by
Andy aka
·
2024-05-06T11:41:21Z (8 months ago)
- > _Why are CY capacitors on the source side, and not on the load side?_
I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential "victim" of that interference).
The Y capacitors on the right equalize (both lines) the interference that the switch mode power supply naturally generates. In doing that, they naturally improve the performance of the CMC. In other words, if both lines on the right are made to have the same interfering voltage (with respect to earth) then the CMC does a much better job of reducing the interference coupled back to the port on the left.
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. That port naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential "victim" of that interference).
- The Y capacitors on the right equalize (on both lines) the interference that the switch mode power supply naturally generates. In doing that, they naturally improve the performance of the CMC. In other words, if both lines on the right are made to have the same interfering voltage (with respect to earth) then the CMC does a much better job of reducing the interference coupled back to the port on the left.
#4: Post edited
by
Andy aka
·
2024-05-06T11:40:01Z (8 months ago)
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential receiver of that interference).Hence, the Y capacitors on the right equalize common mode interference voltages that the switch mode power supply will naturally generate. In doing that, they make the CMC perform better. If both lines on the right are made to have the same interfering voltage then the CMC does a much better job of reducing the interference coupled back to the port on the left.
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential "victim" of that interference).
- The Y capacitors on the right equalize (both lines) the interference that the switch mode power supply naturally generates. In doing that, they naturally improve the performance of the CMC. In other words, if both lines on the right are made to have the same interfering voltage (with respect to earth) then the CMC does a much better job of reducing the interference coupled back to the port on the left.
#3: Post edited
by
Andy aka
·
2024-05-06T10:52:22Z (8 months ago)
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential receiver of that interference).
Hence, the Y capacitors on the right reduce common mode interference voltages that the switch mode power supply will naturally generate. In doing that, they make the CMC perform better. If both lines on the right are made to have the same interfering voltage then the CMC does a much better job of reducing the interference coupled back to the port on the left.
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential receiver of that interference).
- Hence, the Y capacitors on the right equalize common mode interference voltages that the switch mode power supply will naturally generate. In doing that, they make the CMC perform better. If both lines on the right are made to have the same interfering voltage then the CMC does a much better job of reducing the interference coupled back to the port on the left.
#2: Post edited
by
Andy aka
·
2024-05-06T10:51:37Z (8 months ago)
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential receiver of that interference).
Hence, the Y capacitors are on the right to reduce common mode interference voltages that the switch mode power supply will naturally generate.
- > _Why are CY capacitors on the source side, and not on the load side?_
- I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter.
- What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line.
- Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential receiver of that interference).
- Hence, the Y capacitors on the right reduce common mode interference voltages that the switch mode power supply will naturally generate. In doing that, they make the CMC perform better. If both lines on the right are made to have the same interfering voltage then the CMC does a much better job of reducing the interference coupled back to the port on the left.
#1: Initial revision
by
Andy aka
·
2024-05-06T10:48:32Z (8 months ago)
> _Why are CY capacitors on the source side, and not on the load side?_ I don't think you are grasping what the image is showing. The port on the left connects to the AC power-line. It naturally supplies power to the circuit on the right via the filter. The port on the right (called power supply) is in fact a switch mode supply like a flyback converter. What is probably confusing you is that the port on the right is labeled "source" and that the port on the left is labeled "load". Those terms are used because the image is intending to show how interference (generated by the switch mode power supply on the right) can be inflicted back on to the power line. Hence, the source of interference is the switch mode power supply and, the port on the left is regarded as the load (a potential receiver of that interference). Hence, the Y capacitors are on the right to reduce common mode interference voltages that the switch mode power supply will naturally generate.