Mitsubishi PLC substrate has a reserved slot when the module address is determined - Database & Sql Blog Articles

L0504-Murata muRata common mode inductor 90Ω 150mA

When working with Mitsubishi PLCs, up to 8 modules (excluding the CPU) can be installed on a single PCB. As shown in the figure, when all slots on the PLC substrate are filled with modules, the module addresses can be determined based on their actual I/O configuration. However, if there are reserved slots between the installed modules, it becomes unclear how many I/O points are reserved for those empty slots—whether it's 32, 64, or 128 points. This uncertainty makes it difficult to determine the correct address for modules that come after the reserved slots.

In such cases, it's essential to configure the number of I/O points reserved for each empty slot within the PLC parameters. Here’s how you can do it:

1. Double-click on "Parameters" and then select "PLC Parameters" from the Project Manager.
2. A pop-up window titled "Parameter Settings" will appear. Click on the "I/O Assignment" tab.

Once in the "I/O Assignment" tab, you can define the number of I/O points occupied by each module installed in a slot. This includes specifying the number of points for any reserved slots. For example, in the figure, slot 3 is marked as a reserved slot, and you can set its I/O point count accordingly.

The following options are available in this window:

• Type: Choose the type of module installed in the slot. If no module is installed, select "Empty."
• Type Name: You can assign an identifying name to the module for easier reference.
• Points: Select the number of I/O points that the module occupies.
• Start XY: This allows you to manually define the starting address for the module's I/O.

By properly configuring these settings, you ensure accurate addressing and avoid conflicts in your PLC system, especially when dealing with reserved slots. It's a crucial step in setting up a reliable and well-organized control system.