One way to avoid EMI problems is to _.
Select one:
a. run low-voltage cable close to power cables
b. use fluorescent lights
c. use ungrounded metal pathways
d. terminate unused conductors at both ends
The correct answer and explanation is:
Correct Answer: d. terminate unused conductors at both ends
Explanation:
Electromagnetic interference (EMI) is a phenomenon where electromagnetic signals from one source interfere with the operation of electronic devices or communication systems. EMI can lead to signal degradation, equipment malfunctions, or even failure of sensitive systems. Proper techniques in cable management and shielding are crucial to minimize EMI problems.
One effective way to avoid EMI problems is to terminate unused conductors at both ends. This practice helps reduce the potential for these conductors to act as antennas that pick up and transmit EMI. Unused conductors, when left open, can pick up electromagnetic signals from the environment, potentially introducing noise into the system. By terminating these conductors at both ends, you effectively ground them or tie them to a stable voltage reference, preventing them from acting as receivers or transmitters of unwanted signals.
In contrast, the other options contribute to EMI or fail to mitigate it effectively:
- Running low-voltage cables close to power cables (Option a) can exacerbate EMI because power cables often carry high currents that generate electromagnetic fields. These fields can couple into low-voltage signal cables, causing interference.
- Using fluorescent lights (Option b) can introduce significant EMI into nearby electronics. Fluorescent lights use ballasts that generate high-frequency noise, which can radiate or couple into electrical systems.
- Using ungrounded metal pathways (Option c) can also increase susceptibility to EMI. Proper grounding is critical for shielding and dissipating unwanted electromagnetic energy.
In summary, terminating unused conductors at both ends minimizes their ability to interact with EMI sources and reduces potential interference in the system. This practice is an essential part of maintaining reliable and noise-free electronic communication and control systems.