APPLICATIONS DALI MCU
Figure 4: Wiring scheme with 4 control points for addressing up to 50 ECG
Laying the control line in indoor installations is generally not
difficult. For the two control wires (DALI signal), you can use
two wires in the same 5-pole NYM cable that provides the
mains supply. You may chose any arrangement for the
parallel wiring, but a closed circuit of the control line is not
permissible. Moreover, the total running length of the control
line must not exceed 300m.
It is important to observe correct polarity of the feed cables
when connecting the control line with two or more DALI MCU
control devices.
Because each of the devices has its own power supply, the
connections must not be mixed up – i.e. the positive wire
must be connected to Da+ and the negative wire must be
connected to the Da- connector of the control device.
Erroneous wiring, however, will not destroy the device,
because the DALI MCU comes with an inverse-polarity
protection feature – however, correct operation will only
resume when the wiring has been corrected to match device
polarity. It is not necessary to observe control line polarity on
the ECG side.
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