These distributed I/O modules may be installed in a cabinet, in an enclosure as for electrical devices or in a protective box placed as close as possible to the sensors and preactuators.
They may be mounted side by side (horizontally or vertically) in which case the minimum space between two modules is determined by the fixing lugs. The maximum distance is determined by the length of the extension cable.
The following drawing shows horizontal side-by-side installation for the TBX IP20 modules.
The following drawing shows vertical side-by-side installation for the TBX IP20 modules.
When they are mounted one above the other the spacing, which must be at least 4 to 5 cm, is determined by the length of the cable to the extension unit.
The following drawing shows TBX IP20 modules mounted one above the other.
d
Spacing determined by the extension cable (4 to 5 cm min.). 
