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5.4.2 Power connection
A plug-in connector is led out at the rear. The assignment is:
*The DU is supplied as standard with 120 Ω bus terminating resistor (terminator).
If the DU is not the last device (see Chap 5.5), it must be removed when fitting (the CAN-Bus).
If the DU is the last device, the CAN-Bus must simply be added.
5.5 System connection
An overview of the electrical configuration of the overall system is given by the following graphics:
(The illustration shows the redundant configuration with 2 power supplies and 3 optional DUs.)
The bus terminating resistor is already implemented in the MU. Thus one side of the bus (on the left
in the diagram) is sealed off. The other side of the bus must be terminated on CAN H and CAN L on
the last device via a 120 Ohm resistance.
Only IGEMA components belonging to the EWLI-3B system may be operated on this CAN-Bus
control cable (1xMU; 1xCU, X x DU). The short-circuit-proof 24V voltage of the CAN-Bus is
120 Ω*
Terminator
Terminator
Mains adapter
Mains adapter
