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Special Note when using MicroLogix 1500 controllers: When deleting power supplies and cables from an I/O configuration for MicroLogix 1500 controllers, the remaining configuration may appear to be represented incorrectly on the chassis display. This, however, is not the case.
Explanation: Power Supply and Cable items don't occupy slots. Although they may appear to do so in the configuration display, internally they are just replacing the unused slot in the diagram. Therefore, when deleting a non-I/O item, it is actually just being marked as unused. And the resultant display is correct.
Important: When configuring I/O for a MicroLogix 1500 controller, note that a 1769- HSC, and a 1769-SDN cannot be more than 4 slots from the power supply. A 1769-OB32 cannot be more than 6 slots away from the power supply. Other modules are allowed to be 8 slots away. Project verification will give an error if these modules are placed too far away from a power supply.