Hi,

Lubomir B.

 (The instance of type 'SYSTEM.AnalogInput' could not be copied because an instance of this type already exists on this CPU.

 basically the cause and solution is the message itself.

The block (type) is already used in the regular program or in another software unit. A "type" can be used multiple times within a software unit or outside of a software unit, but not in both at the same time.

Basically it is kind of logical. Software units are designed to be used/configured/programmed in parallel. That is also the reason you have to use relations if there is an access outside/between units.
But a library type is not realy a copy, it is somehow the same block. If changed outside of a software unit or in another software unit, this would effect all sources.

So you have to decide were the block should be used.
Otherwise you can create a copy of the block and add the copy as a second type. But afterwards you have to manage both types of course.

regards

sancruz