What is service mains in power distribution system January 9, 2024January 9, 2024 by admin A service mains is usually a small cable that connects the distributor to the consumers terminals. In power distribution schematic below, service mains are indicated in red color. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on WhatsApp (Opens in new window)