How to add slack to Inventor cables?

There are several ways for adding slack to cables in Inventor Professional:

1. Embedded Length
The length of the wire that will be inserted into a connector or pin. This value can be defined in custom properties of the connector (splice) or pin (splice pin). See also the harness settings (Wires/Cables tab).

2. Global Slack
Extra length added to wires and cables as a percentage of their length. See the harness settings (Wires/Cables tab).

3. Service Loop
Value applied to segment which adds length to the segment itself and all routed wires in the segment. You can define this option at segment custom properties (segments with routed wires/cables).

4. Round Off/Round Up
A parameter used to increase the wire and segment length to the specified increment defined in harness settings (General tab). In this way you can specify a realistic length that can be easily measured and cut.

So the total adjusted lenght is computed as the original length of the wire with the addition of the Embedded Length, Global Slack, Service Loop and Round Up values.