Table 16: ZEC510 status LEDs
LED label
LED color Normal state Description of LED states
POWER
Green
Steady on
Off steady = The controller has no power
On steady = Operating normally, and primary
voltage powers the controller
FAULT
Red
Steady off
Blink - 2 Hz = Download or startup is in
progress. The controller is not ready for normal
operation. Sensor bus devices are offline.
Rapid blink = Sensor bus communications
problem
Off steady = No faults
On steady = Device fault or no application
loaded
SA BUS (sensor
bus)
Green
Blink - 2 Hz
Blink - 2 Hz = Data transmission. Normal
communication
Off steady = No data transmission. Auto baud in
progress
On steady = Communication lost. Waiting to
join communication ring
FC BUS (zone bus) Green
Blink - 2 Hz
Blink - 2 Hz = Data transmission. Normal
communication
Off steady = No data transmission. Auto baud
not supported
On steady = Communication lost. Waiting to
join communication ring
EOL
Amber
Off
On steady = EOL is active
Off steady = EOL is not active
Communication bus problems
Communication problems include cases when devices fail to connect or connect intermittently.
One of the following factors can influence the behavior of the zone communication bus and cause
communication problems.
Input and output wiring problems
If you wire the ZEC510 incorrectly, communication problems can occur.
Invalid address
The VAV controller must have the address switch set to a range between
4
-
127
.
Duplicate addresses
Two or more devices on a communication bus cannot have the same address. If two devices on the
same bus have the same address, performance can degrade or serious communication problems
can occur. You can check for duplicate addresses in the following ways:
• If a specific device is not communicating, remove the device and check if the device address
remains online on the SBH. Alternatively, change the address of the device to the next
available address, and check if the old device address remains online. This determines if
another device is using the address.
29
Verasys ZEC510 VAV Controllers Installation Guide
