The AX8000 servo drive series is suitable for operation on grounded single-phase or three-phase grids. Connection to TN grids (French: Terre Neutre) or to TT grids (French: Terre Terre) is possible without further measures. For all other grids, operation is only possible on so-called isolating transformers. An isolating transformer is a mains transformer that transmits the mains voltage to the secondary winding via a protective isolation (electrical isolation), where it makes a grid available with a grounded star point.

The use of an isolating transformer is possible with the following grid forms:

• - IT grid (French: Isolé Terre)
• - Ungrounded grids
• - Asymmetrically grounded grids

Typical American grids for which an isolating transformer is required:

• - Corner-grounded Delta system / solidly-grounded Delta system
• - Ungrounded Delta system
• - Ungrounded split-phase system (2 phases, 180° phase shift)

Note: Operation on the split-phase system with a grounded midpoint is allowed without an isolating transformer