Permitted voltage supply systems

TN and TT systems – voltage systems with directly grounded star point

Use is possible without restrictions.

IT systems – voltage systems with non-grounded star point

Use is only permitted with adherence to the following measures:

Size 0S, 0L:

1. Only deactivate the EMC capacitors when used in IT systems, see chapter Use in IT systems for sizes 0S and 0L.
2. Mark this on the nameplate in the "IT system activated" box provided for this purpose.

Sizes 3 – 8:

3. Remove all existing EMC contact screws from all devices only when used in IT systems. For the positions of the EMC contact screws refer to the product manual > chapter "Device structure" > Size 3.
4. Mark this on the nameplate in the "IT system activated" box provided for this purpose.

INFORMATION: The EMC limit values for interference emission are not specified for voltage supply systems without grounded star point (IT systems). The effectiveness of line filters is severely limited.

Voltage systems
with grounded outer conductor

Use only for nominal line voltages up to max. 240 V.