BGH GMV6 Technical Sales Manual page 132

NOTES:
a. In modular ODU, if there're several ODU modules, the first set of ODU module in the communication
cord must be the master module and shall not be connected to IDU (master module is set by SA8 of
ODU main board)
b. In modular ODU, if there're several ODU modules, then IDU must be connected to the subordinate
module of the last ODU (subordinate board is set by SA8 of ODU main board)
c. Conduct separate wiring for the communication cord and power cord to avoid interference.
d. The length of communication cord must be proper, no overlap-connected is allowed.
e. The IDU must adopt series connection and the last IDU must be connected to the matched resistance
(provided in ODU sub-assy list).
f. Wiring method and setting of central controller shall refer to related manuals.
9.3.2 Communication connection method between IDU and wired controller
There are 4 connection ways between IDU and wired controller, please refer to the follow:
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