BECKHOFF EP9128 - Manual (Page 36)

Mounting and cabling
Fig. 44: EP92x4­0023, Connectors for Power In and Power Out
Electrical isolation
Digital modules
In the digital input/output modules, the grounds of the control voltage (GNDs) and the auxiliary voltage
(GNDp) are connected to each other!
Check this at the documentation of each used EtherCAT Box.
Analog modules
In the analog input/output modules the grounds of the control voltage (GNDs) and the auxiliary voltage
(GNDp) are separated from each other in order to ensure electrical isolation of the analog signals from the
control voltage.
In some of the analog modules the sensors or actuators are supplied by Up ­ this means, for instance, that in
the case of 0...10 V inputs, any reference voltage (0...30 V) may be connected to Up; this is then available to
the sensors (e.g. smoothed 10 V for measuring potentiometers).
EP9128 36 Version 2.1.0