Data Sheet for Product

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Siemens Climatix range CB1Q3900en_02
Building Technologies 30.11.2009
Connecting the extension modules
Specification for pheripheral bus cable and power supply:
• If the total length of the pheripheral bus cable exceeds 3 m, shielded cables
must be used (L1 + L2 + Lx = >3 m)
•
If the total length of the pheripheral bus cable is less than 3 m, shielded cables
are not required
(L1 + L2 + Lx = <3 m)
• Each shield must be grounded at one side only
• Maximum bus cable length is 30 m (L1 + L2 + Ln = <30 m)
• To connect the bus cable to the modules, use the board-to-wire terminals
• GND of the power supply must be grounded (see illustration above)
• Connections from one plant to another can be effected via a 2-wire bus cable
(A+ and B-). In this case, the modules must be powered by a separate supply
(see illustration above). All plants must have the same GND. GND of the power
supply must be grounded at one point only
• Refer to the pass-through-current rules for limiting the current across each de-
vice within the individual limits
Cabling and
grounding rules