Daisy-Chain Wiring - Distech Controls ECL-VAVS Installation Manual

10
9
8
E
7
6
5
4
3
2
1
0
100
(30)
Figure 11: Maximum Number of VAVS Devices on a Daisy-Chain at Evenly Spaced Intervals
Laboratory testing conditions for the above graph are as follows:
£
Distance between each VAV is evenly spaced along the entire wire length
£
Transformer specification: 100VA (120/24VAC)
£
Tested at room temperature with low voltage line conditions: 108VAC (50Hz)

Daisy-Chain Wiring

Use an external fuse on the 24VAC side (secondary side) of the transformer, as shown below, to protect all controllers against power line spikes.
Maintain consistent polarity when connecting controllers and devices to the transformer. That is, the COM terminal of each controller and each peripheral
should be connected to the same terminal on the secondary side of the transformer.
Failure to maintain consistent polarity throughout the entire network will result in a short circuit and/or damage to the
controller!
The COM terminals of the controller are internally wired to the 24V COM terminal of the power supply. Connecting a
peripheral or another controller to the same transformer without maintaining polarity between these devices will
cause a short circuit.
Daisy Chain Performance
D A
F
C
150 200
(45) (60)
B
A
VAVS + SmartVue (AWG18)
B
VAVS + SmartVue (AWG16)
C
VAVS + SmartVue + 2DO (1,6VA each) (AWG18)
D
VAVS + SmartVue + 2DO (1,6VA each) (AWG16)
E
VAVS + SmartVue + SmartVue CO2 + 2DO (1,6VA each) (AWG18)
F
VAVS + SmartVue + SmartVue CO2 + 2DO (1,6VA each) (AWG16)
250 300
(75) (90)
Total Wire Length Feet
(meters)
350 400 450
(105) (120) (135)
500
(150)
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