CarterRoll™ conveyors, typically configured with 30" zones, run only as needed to move product. This "on-demand/as-needed" approach conserves power, reduces wear and tear on the system, and reduces operating noise. Each zone, comprised of a set of idle rollers driven by a powered roller, is activated only if the next zone is empty. The zoned design also provides zero pressure accumulation capability and keeps products from touching one another during transport. Upstream zones automatically accumulate when downstream backups occur. Designs can include jam detection and visual indicators, as well as easy to install "plug-and-play" control modules. Also, the various conveyor design choices provide for an infinite number of configurations and flexibility in layout.