Tpo Function Block - Honeywell UMC800 Reference Manual

Function Blocks

2.73 TPO Function Block

Description
The TPO label stands for Time Proportional Output. This block is part of the Loops category. It looks
like this graphically on the Control Builder.
Function
Proportions the amount of ON time and OFF time of a Digital Output over a user defined cycle time.
On Time = [cycle time * (IN - range lo)] / (range hi - range lo)
OFF Time = cycle time - On Time
If On Time < minimum ON time, then On Time = 0.0
If OFF Time < minimum OFF time, then OFF Time = 0.0.
Input
Analog Input value in Percent(%)
Block Properties
Double click on the function block to access the
function block properties dialog box.
Block Order (Read Only)
You can change the assigned execution order
number by selecting "Execution Order" in the
"Configure" menu and arrange the order to suit
your control strategy.
Configuration Parameters
You must configure the TPO function Block
parameters to the desired value or selection that
matches your operating requirements.
Table 2-57 describes the parameters and the
value or selection.
212 Function Block Reference Guide
Continued next page
3/99