Auto-Zone Control Systems Auto-Zone CV-C Controller Installation Guide (Version 01A) - Manual (Page 11)

Auto-Zone CV-C Section 2
Sequence of Operation 2-1
Initialization Initialization Initialization Initialization
On system powerup LED1 and LED2 are extinguished. After 5 seconds LED2 will blink
out the address of the controller ( Address Switch Setting ). Following this, the LED2
LED will extinguish for another 5 seconds and then begin to blink for a 20 second startup
delay. At the conclusion of this 20 second period, the LED2 LED will begin blinking a
diagnostic code every 10 seconds. This code is described later in this document. The
duration of a powerup initialization sequence is roughly 1 minute plus the user defined
Staggered Start delay described later in this document.
During this initialization period, the controller retrieves all operating setpoints from its
non-volatile EEPROM memory and initializes all outputs to an off condition.
NOTE: All future references to the Constant Volume
Configurable unit in this document use CVC as the
designation.
Operating Summary Operating Summary Operating Summary Operating Summary
At all times, after the conclusion of the initialization sequence, the CVC performs a
specific set of operating instructions in the following order: ( a - g Repeat Continuously )
a. Read Analog Inputs for Temperatures, Overrides and Lockout or Reset contact
closures.
b. Check the RS-485 communications port for any new setpoints from the System
Manager and keeps the status updated for the System Manager.
c. If the push-button override is active, it checks the timer to see if the override is
finished.
d. Calculates the current occupied/unoccupied mode from its internal week
scheduling.
e. Calculates what state the output relays and analog output should be set to.