As my knowledge you can add or remove any I/O card without any plantshutdown(if your Cyclic load is below critical levels) But on the other hand, you need to supply I/O Card with power, so there is always risk for short circuit etc.
I guess the best way is, you need to add some spare cards on your existing system.
As far as I know it should be documented in the manuals (most likely in the Mounting and Installation Guide). But to answer that question correctly you also have to provide the system you're talking about. ABB has various I/O systems, and the procedure can vary.
I think that is not possible - at least adding of a new modules to HW configuration or connecting of variables to the new modules will require download of application with stop of cyclic execution. Adding of IO's to the modulebus Online (without switch-off of the power supply) is against what is described in the manuals. It could work, but at own risk. It is better to add the spare modules in the beginning, but even with this you can't skip download when connect the new variables to it later on
Hello, Yes HCIR of extended IOs is possible online without cluster shutdown and the only thing you have to take care is ensure other IOs are running without errors and check electrical bus is ok and system load is less than 80%