Distech Controls ECB-VAV, User Manual

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64 Network Guide
Maintain consistent polarity when connecting controllers and devices to the transformer. That
is, the 24V COM terminal of each controller and each peripheral
may be connected to the
same terminal on the secondary side of the transformer. This transformer terminal must be
connected to the building's ground.
Recommended 24V Power Cable
The table below lists Distech Controls' recommended power cable.
24V Power Supply Connection
Use an external fuse on the 24VAC side (secondary side) of the transformer or DC power sup-
ply, as shown in
Figure 38 and Figure 39 , to protect all controllers against power line spikes.
For any given number of devices, wire the power supply as shown in Figure 38 and Figure 39 .
Maintain consistent polarity when connecting controllers and devices to the transformer. That
is, the 24V COM terminal of each controller and each peripheral should be connected to the
same terminal on the secondary side of the transformer.
Figure 38: Power wiring – 24VAC: Maintain Consistent Polarity with all Controllers’ Power Connections
Table 14: Distech Controls Recommended 24V Power Cable
Cable Type
AWG - Number
of Conductors Non-Plenum Applications (FT4) Plenum Applications (FT6)
Part Number O.D. (Ø) Part Number O.D. (Ø)
18-2 CB-W181P-1002 5.0mm 0.20in. CB-W181P-2051 5.0mm 0.20in.
16-2 CB-W161P-1031 4.8mm / 0.19in. CB-W161P-2062 4.8mm / 0.19in.
14-2 CB-W141P-1081 7.2mm / 0.29in. CB-W141P-2013 7.2mm / 0.29in.
Connecting the power source to Electrical System Ground is not a requirement for
proper system operation. However it is good installation practice to do so in order to
maintain the same potential between all controllers and Protective Earth.
Controller 2
Transformer
Controller 1
AC
24V AC/DC
24V COM
Fuse: 4 A Max .
Fast Acting
24 VAC
OPTIONAL : Connect to Electrical System
Ground - At Power Supply Only
24V AC/DC
24V COM