Function Blocks
TPO Time Proportional Output Function Block
Revision 11 HC900 Hybrid Control Designer Function Block Reference Guide 407
2/07
Configuration parameters
Table 117 TPO configuration parameters
Properties Group Parameter Index # Parameter Description Value or Selection
Address Rack
0 Address of selected Rack
Enter a value:
from 1 to 5
I/O Module
Address of selected I/O module
Enter a value:
from 1 to 16
Channel
Channel on selected I/O Module
Enter a value:
from 1 to 16*
Range Range Hi
1 High Range Value
–9999 to 9999
Default = 100
Range Lo
2 Low Range Value
–9999 to 9999
Default = 0
Cycle Settings Cycle Time
N/A Output Cycle Time
1 to 120 seconds
Default = 20
Min Off
Time
4 Minimum OFF time
to 15.0 seconds
Default = 0.0
Min On
Time
5 Minimum ON time
to 15.0 seconds
Default = 0.0
*For HC900 controller’s 32 Channel DO Module, outputs 17 through 32 may not be used
for TPO (Time Proportioning Output), PPO (Position Proportioning Output) or TPSC (Three
Position Step Output) output types.
Example
HFigure 115 shows a Function Block Diagram using a TPO function block. Time Proportioning outputs are
commonly used for electrically heated applications where regulating the amount of ON time vs. OFF time
of a heater is used to control temperature. In the example the TPO output is used to activate a relay output
to control a heater.