Distech Controls ECB-VAV, User Manual

Page: 112 / 138

110 Network Guide
Device does not com-
municate on the BAC-
net MS/TP network Absent or incorrect
supply voltage (for
24V controllers) 1. Check if the device is showing the 'Poor- Quality Power' status code (for 24V
controllers). See
Table 30 for a list of fault codes.
2. Check power supply voltage between 24VAC/DC ±15% and 24V COM pins
and ensure that it is within acceptable limits (for 24V controllers).
3. Check for tripped fuse or circuit breaker.
Overloaded power
transformer (for 24V
controllers) 1. Check if the device is showing the 'Poor- Quality Power' status code. See Table
30 for a list of fault codes.
2. Verify that the transformer used is powerful enough to supply all controllers.
See
Transformer Selection and Determining the Maximum Power Run Length on
page 43.
Network not wired
properly Double check that the wire connections are correct.
Absent or incorrect
network termination Check the network termination(s).
Max Master parameter Configure the Max Master to the highest MAC Address of any device on the MS/
TP data bus. See Setting the Max Master and Max Info Frames on page 34.
There is another con-
troller with the same
MAC Address on the
BACnet MS/TP data
bus Each controller on a BACnet MS/TP data bus must have a unique MAC Address.
Look at the MAC Address DIP switch on the faceplate of each controller. If it is set
to 0 (all off), use an Allure EC-Smart-Vue sensor to check the MAC Address.
There is another con-
troller with the same
Device ID on the BAC-
net intranetwork Each controller on a BACnet intranetwork (the entire BACnet BAS network) must
have a unique Device ID. Use an Allure series communicating sensor to check
the Device ID of each controller. See
Adopting a Numbering System for MAC
Addresses, Device Instance Numbers, and Network Numbers on page 36.
BACnet data bus
polarity is reversed. Ensure the polarity of the BACnet data bus is always the same on all devices.
See
BACnet MS/TP data bus is polarity sensitive on page 146.
Cut or broken wire. Isolate the location of the break and pull a new cable.
The BACnet data bus
has one or more
devices with the same
MAC Address. See Adopting a Numbering System for MAC Addresses, Device Instance Num-
bers, and Network Numbers on page 167.
The baud rate for all
devices are set to
AUTO At least one device must be set to a baud rate, usually the data bus master. See
Setting the Baud Rate for ECB-Series Controllers (optional) on page 101.
The device is set to a
MAC Address in the
range of 128 to 255. See if the STATUS LED on the device is showing a fault condition. See Table 28
for a list of fault codes.
This range is for slave devices that cannot initiate communication. All Distech
Controls' devices are master devices and must their MAC Address set accord-
ingly. See
Device Addressing on page 164.
The maximum num-
ber of devices on a
data bus segment has
been exceeded. Use a repeater to extend the BACnet data bus. See Maximum Number of BACnet
MS/TP Devices on a Data Bus Segment and Baud Rate on page 148.
Table 27: Troubleshooting ECB Device Symptoms
Symptom Possible Cause Solution