Auto-Zone Control Systems Auto-Zone Plus Systems Installation & Operation (Version 03A) - Manual (Page 189)

Auto-Zone Plus Section 4
Start-Up and Troubleshooting 4-39
During calibration, a “flag” is read by the Zone Manager which prevents the user from
reading any status values or changing any setpoints. The Zone Manager status screens
will indicate that zone to be calibrating. Also during this time, the zone is eliminated from
any HVAC voting.
3.1.3 Operating Summary
At all times, after the conclusion of the initialization and calibration sequence, the Zone
Controller performs a specific set of operating instructions in the following order:
a. Reads analog inputs for temperatures, overrides and setpoint offset adjustments.
b. Checks the RS-485 communications port for any new setpoints from the Zone
Manager and keeps the status updated for the Zone Manager. (If RS-485
communications is lost, the controller goes into a protection mode, described
later)
c. If the push-button override is active, it checks the timer to see if the override is
finished.
d. Calculates what the damper position should be and what condition the relays
should be in if the optional relay expansion board is connected.
e. Updates the diagnostic SCAN LED blinking.
f. Stores data in the internal trend log if ready for another log.
g. Repeats steps a - f continuously.