HEIDENHAIN PROFIBUS-DP (DPV2) - Manual (Page 17)

Encoder gateway installation
17
The cable gland gateway shall be equipped with twisted pair
shielded cable in accordance with EN 50170 and PROFIBUS
guidelines. The guidelines recommend a conductor area higher
than 0,34 mm 2 . Permissible outer cable diameter is ø 8 mm to ø
10 mm for the bus lines cables. Located inside the back cover are
four screw terminals containing the required bus line terminals
marked A and B. Cable glands not used, should be replaced with
a M16 filler plug to ensure proper sealing.
Note: Tighten all screws in the terminal, even if no cable has
been attached.
Note: The two A terminals are internally connected to each
other and the two B terminals are also connected to
each other so it does not matter to which the bus lines
are connected to.