Distech Controls ECL-VAV Series Hardware Installation Manual page 4

Daisy-chaining controllers is not permitted when a controller's
expected power consumption including external loads is over 15VA. In
this case the controller must be connected to the 24VAC transformer in
a star topology. The transformer must be installed in close proximity to
the controller according to the cable gauge and total load.
Table 1: Maximum Number of VAV Devices on a Power Run
(Daisy-Chained)
AWG Power Run Maximum
Total Cable Number of
Length Devices @
7 VA per
device
4
14 75M (250 feet) 4
4
14 60M (200 feet) 5
4
14 45M (150 feet) 5
4
14 30M (100 feet) 5
16 60M (200 feet) 3
16 45M (150 feet) 5
16 30M (100 feet) 5
18 45M (150 feet) 3
18 30M (100 feet) 5
1. Typical VAV with 1 Allure Series Communicating Sensor (without
CO2 sensor) and actuator activated. No external loads.
2. Typical VAV with 1 Allure Series Communicating Sensor (without
CO2 sensor), 2 triac loads (1.6 VA each), 1 analog output (20 mA),
and actuator activated.
3. Typical VAV with 1 Allure Series Communicating Sensor (without
CO2 sensor), 4 triac loads (1.6 VA each), 2 analog outputs (20 mA
each), and actuator activated
OR
Typical VAV with 1 Allure Series Communicating Sensor with CO2
sensor, 2 triac loads (1.6 VA each), 1 analog output (20 mA), and
actuator activated.
4. Device terminals are not capable of accepting two 14 AWG wires
(when daisy-chaining devices). Use a wire nut with a pig tail to
make such a connection.
Use an external fuse on the 24VAC side (secondary side) of the
transformer, as shown in Figure 8, 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.
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.
Fuse: 4 A Max.
Controller 1
Fast Acting
24V AC
24V COM
24 VAC
Controller 2
24V AC
24V COM
Figure 8: Power wiring
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.
4/12
Maximum Maximum
Number of Number of
Devices @ 10 Devices@ 15
2
VA per device VA per
1
device
2 1
3 2
4 3
5 4
2 1
3 2
4 3
2 1
3 2
AC
Transformer
OPTIONAL: Connect to
Electrical System Ground -
At Power Supply Only
Jumper Identification and Configuration
Controllers have the following onsite configurable jumpers.
3
Wireless
Port
Figure 9: ECL-VAV Series and ECL-103 Controller Jumper
Locations
Net to Subnet Port Settings
Enabled Disabled*
Digital Outputs (DO)
Power Source Jumpers for
DO3 & DO4
Triac Internal Triac External
Power* Powered
Jumpers for
DO1 & DO2
* Factory-default positions
Subnet
Port