Monitoring and Operating the Controller 
208  UDC3500 Universal Digital Controller Product Manual  3/07 
4.10.2  Tune for Duplex (Heat/Cool) 
Accutune for applications using Duplex (Heat/Cool) control. 
The controller must be configured to have two local setpoints unless Blended Tuning is 
desired (see below). See Subsection 3.20- Control Set Up Group for details on 
configuring two local setpoints. During tuning, the Accutune III process assum
es that 
Local Setpoint 1 will cause a Heating demand (output above 50%), and the tuning 
parameters calculated for that setpoint are automatically entered as PID SET 1. Likewise, 
Accutune III assumes that Local Setpoint 2 will cause a Cooling demand (output less 
than 50%), and the tuning parameters calculated for that setpoint are automatically 
entered as PID SET 2. 
Configuration Check for Duplex 
See Subsection 3.10 – Accutune Set Up Group f
or details. 
Make sure: 
•  TUNE has been enabled 
•  DUPLEX has been configured to Manual, Automatic or Disabled