Before I can answer your query, please answer the following questions:
1. What do you do when the equipment that is out of order is sent for repair? Do you use another similar equipment in its place?
2. If the answer to the above question is yes and you use an identical equipment in place of it to keep the system running, you may study “Rotating Items” application in Maximo. This functionality is used to track all such items that are required to be repaired and installed back after getting the services received.
Rotating Item uses three identifications for all such equipment:
1. Equipment Number (Tag number of the item where used in field)
2. Item number (Stock code, the number allocated by warehouse)
3. The Serial Number (The number provided by the Manufacturer).
Please feel free to contact me, if you need any help after going through the help topic of Rotating Items in Maximo.