|
Problem |
Solution |
|---|---|
When making changes to an application in
commissioning mode an Alert dialog box displays the following
information: |
This specific behavior can be observed when making certain changes to a 6.2 application in commissioning mode without having the 6.2.2 firmware patch installed. Always apply the latest patch of firmware if you configure your applications with newer tool versions. |
|
Applications configured as VAV type fail download at 99% and the
controller shows a status of |
Check your CFM values for control and application configuration. VAV applications limit the MAX CFM Flow to 9,999 with a maximum 9.9 inch inlet connection. CCT does not support VAV applications where Box sizes are greater than the above stated flow and inlet size. Any attempt to configure applications for VAV Box sizes 10 inches or larger with 10,000 CFM air flow or greater will result in an application download failure to the configured controller. To accomplish a successful configuration for this VAV Box size the application will require customized or modified logic with related modules and connections. |
|
The Zone Temperature control does not seem to react as quickly as expected when it is in unoccupied mode. The zone temperature overshoots the unoccupied heating or cooling setpoint during unoccupied operation. See Figure 1. |
The Satisfied Timer Duration value of the Unoccupied Sequencing (VAV) is set to too high. Reduce this value to decrease the overshoot. The Satisfied Timer Duration works as follows: When unoccupied, the zone temperature is monitored to determine when the temperature exceeds the band specified by the two unoccupied temperature setpoints. When this occurs, the Unocc Status is set to the appropriate heating or cooling state. The module remains in this state until the appropriate setpoint has been satisfied for the Satisfied Timer Duration. After that period of time, the status is set to Satisfied. |
|
Figure 1. Changing Satisfied Timer Duration
| |