Data Sheet for Product

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Siemens Climatix range CB1Q3900en_02
Building Technologies 30.11.2009
DIP switch configuration of extension module
Slave address
(controller)
Switch 1 Switch 2 Switch 3 Switch 4 Switch 5 Schematics
27 On On Off On On
28 On On On Off Off
29 On On On Off On
30 On On On On Off
31 On On On On On
The same address of extension module must be set in the application program of
the controller. Zero cannot be set as the slave address.
Connecting the extension modules
The pass-through current is the maximum current that can flow across each device
to limit the current within the defined safety levels.
When extension modules are powered by a controller or some other extension
module over the peripheral bus lines, a calculation is necessary to make certain
that the total apparent power for this group of devices does not exceed 96 VA.
If this is the case, the group of controllers and extension modules must be subdi-
vided into 2 subgroups, enabling each of them to draw less than 96 VA.
Note: When using AC 24 V power supply, power consumption is higher than that
resulting from DC 24 V, the reason being the better efficiency of DC power supply.
As a result, with DC 24 V power supply, the number of extension modules that can
be connected to the same power supply line is greater than with AC 24 V.
Maximum number of extension modules
31 (1…31)
Maximun pass-through current per group
96 VA
Cable lengths
Total of max. 30 m
Below are some examples that show a number of choices:
The following table provides the maximal capacity of the controllers, considering
the full load configuration for each device. For this reason, the values used in other
configurations can be smaller than those stated here.
Note

Pass-through
current rules