Operating Characteristics - Controller Modes 
150   HC900 Process Controller Installation and User Guide  Revision 19 
    06/14 
Table 22 – Controller Operating Modes 
Mode Name  Functions in selected mode 
RUN 
I/O scanning (Controller and Expander Racks) 
Function block execution; outputs are set according to function block algorithms. 
Monitoring of Diagnostics (controller rack and I/O expander racks) 
Detection of I/O Modules 
Other functions permitted: 
•  Downloading of configurations 
•  Indications of Forces at Status LEDs on I/O modules 
Other functions NOT permitted: 
•  AI calibration 
•  AO calibration 
PROGRAM 
I/O scanning (Controller and expansion Racks[C50 CPU only]) is performed, but 
function blocks are not executed, and all outputs (digital and analog) are set to OFF.  
(See Note 1.) 
Monitoring of Diagnostics (Controller and Expander Racks) 
Detection of I/O Modules 
Other functions permitted: 
•  AI calibration 
•  AO calibration 
•  Downloading of configurations 
•  Downloading controller firmware (Program Locked or Program) 
Other functions NOT permitted: 
•  Indications of Forces at Status LEDs at I/O modules 
OFFLINE 
IO scanning (Controller and Expander Racks) is performed, but function blocks are 
not executed, and all outputs (digital and analog) are Frozen (see Note 2) at the 
states they were in when the OFFLINE mode was selected. 
Monitoring of Diagnostics (local and expanded racks) 
Detection of I/O Modules 
Other functions permitted: 
•  AI calibration 
•  Indications of Force at Status LEDs of I/O modules 
Other function NOT permitted: AO calibration 
Note 1: The Off state of the module outputs are defined as: 
•  Digital output - low state 
•  Time proportional Output (TPO) : 0% duty cycle 
•  PPO and TPSC Outputs: Both Fwd and Rev are Off. 
•  Analog output: 0.0 mA 
Note 2: The Frozen states of module outputs are defined as: 
•  Digital output: same state as previous (last active state) 
•  Time Proportional Output (TPO): Same duty cycle as in last active state  
•  PPO and TPSC Outputs: digital outputs are Off to freeze the motor position. 
•  Analog output: same current as previous (last active current level)