What key type should be used to replace a device with the same catalog number?

The correct choice is compatible keying. This key type allows for the replacement of a device with the same catalog number while maintaining the overall system compatibility. In practical terms, compatible keying enables devices to be interchanged without needing to reconfigure the entire system or introduce new settings that might affect the operation.

Using compatible keying ensures that the replacement device will function correctly within the existing network or control scheme, as it's designed to accept and match the parameters of a previously installed unit with the same catalog number. It aligns with the design philosophy of maintaining operational continuity and simplifying the maintenance process, especially in environments where equipment may need to be swapped during repairs or upgrades.

In contrast, exact match keying would require the replacement device to match not only the catalog number but also specific parameters or configurations, which might not be practical in every situation. Disable keying and no keying provide more flexibility but could lead to compatibility issues if the new device does not meet the required specifications or intended functionalities of the system.