eZV-440 Version 2.1 Application Guide
Page 12 of 67
Document Edition 2.5
For more information about trend logs, see the
latest version of the ORCAview Technical Reference manual on the Delta
Controls support web site.
Programming
In the programmable controller, the 3 programs that exist alongside the internal algorithm
allow you to either create your own custom algorithm or override portions of the internal
algorithm to suit your needs. The maximum size of each program is 5 KB.
The programmable controller also allows you to create new I/O, AV, BV or MV objects in the
900-999 range for use in your custom program.
Supported GCL+ Programming Functions, Statements and Operators
The Call Statement is not used in the programmable eZVP-440 controllers. Unlike other
programmable Delta Controls controllers, the 3 programs in the eZVP-440 are automatically
scanned. The eZVP-440 controller scan rate is also designed to be a constant 10 scans/second.
A list of supported and unsupported GCL+ functions and statements for the eZVP-440
programmable controllers is recorded in
on the Technical support web site. The
ORCAview and enteliWEB GCL editors are not aware of these limitations, so using an
unsupported function in an eZVP-440 controller will not register a syntax error in these GCL
editors.
Overwriting the Algorithm
You can overwrite the algorithm by programming specific variables numbered in the 800 range.
For example, if you want to change how the algorithm determines the occupancy state, you
could write your own GCL+ program to set the occupancy MV800 state. Your program must
write more frequently than every 5 seconds else the factory algorithm will recapture control.
The following table displays all the variables that are programmable. For an overview that
shows the entire network of unit modules and how they relate to each other, see the diagram at
the end of this table.
Algorithm
Unit Module
Unit Module’s Function
Programmable Variable
Airflow
Setpoint
Manager
Maintains the
AV830 AirflowSetpoint
Box Mode
Controls “
” by monitoring the room temperature and the
inlet air temperature.
MV801 VAVDuct1BoxMode