What is the main reason for keeping ELV and LV cables separate in containment?

• A. To prevent interference and disruption between ELV and LV cables.
• B. To improve heat dissipation.
• C. To ease labeling.
• D. To reduce installation time.

Answer: (D)

The main concept is preventing interference and preserving signal integrity between ELV and LV systems. LV cables carry higher currents and switching transients, which generate electromagnetic fields and electrical noise. If ELV and LV cables share the same containment, this noise can couple into ELV circuits, causing false alarms, misreads, or degraded performance in systems like fire alarms, CCTV, access control, or data networks. Separation also helps ensure that a fault on the LV side doesn’t affect ELV circuits and makes fault isolation easier, while aiding compliance with safety and installation standards. While factors like labeling or installation time might be influenced, they aren’t the primary reason.