Auto-Zone Control Systems Auto-Zone CV & CV-EX Systems Installation & Operation (Version 01C) - Manual (Page 89)

Auto-Zone CV & CV-EX
Section 4
Start-Up and Troubleshooting 4-11
CV Controller Overview
How It Works
Initialization
On system power-up, the COMM LED remains extinguished for five seconds. After this
delay, the COMM LED will blink out the address of the controller (Address Switch
Setting). The COMM LED will then extinguish for another five seconds and then begin
to blink for a twenty second startup delay. At the conclusion of this twenty second period,
the COMM LED will begin blinking a diagnostic code every ten seconds. See the Blink
Code section of this manual. The duration of a power-up initialization sequence is
roughly one minute.
During this initialization period, the controller retrieves all operating setpoints from its
non-volatile EEPROM memory and initializes all outputs to an OFF condition.
Operating Summary
At all times, after the conclusion of the initialization sequence, the CV controller
performs a specific set of operating instructions in the following order: (1-7 repeat
continuously)
1. Reads Analog Inputs for Temperatures and Overrides.
2. Checks the RS-485 communications port for any new setpoints from the System
Manager and keeps the status updated for the System Manager.
3. If the push-button override is active, it checks the timer to see if the override
is finished.
4. Calculates the current occupied/unoccupied mode from its internal week
scheduling.
5. Calculates what state the output relays and analog output should be set to.
6. Updates the diagnostic COMM LED blinking.
7. Stores data in the internal trend log if ready for another log.