No. As long as the hardware connections for the BUS remain intact, simply turning off one of the expanded power supplies will not affect the other backplanes. The power supply is used only to power the IO modules and does not affect the BUS signals.
Legacy KB System (APS) Data: RESL212573 V1.0, Originally authored by DaSo on 09/24/2013, Last Edited by DaSo on 09/24/2013
Related ranges: Modicon M340