PROBA 5
Doc.nr: 190356
Version: 1.0
Page
64
A Operations of controls
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Cooling and Heating
The cooling switches on at se differential and switches off at se offset.
•
The heating switches on at se offset - differential and switches off at se offset.
Humidifying
The humidifying process switches on at se differential and switches off at se offset.
Gassing
The gassing process switches on at se offset - differential and switches off at se offset.
Proportional outputs for Cooling and Heating
Should an analogue output be used as a proportional output for the cooling, then this output will emit 100% if the
temperature is equal to or higher than se proportional band. At a temperature of se offset
the emission will be 0%. In the intermediate part the output will run linear with the temperature.
Should an analogue output be used as a proportional output for the heating, then this output will emit 100% if the
temperature is equal to or lower than se offset - proportional band. At a temperature of se offset
the emission will be 0%. In the intermediate part the output will run linear with the temperature.
Proportional intergrating output for the Cooling and Heating
When a proportional output is used for the cooling an equilibrium is created whereby there is enough cooling
to compensate the heat development. Thus the output continues to emit and the set point is not reached. The
I-function ensures that the so-called ‘control error’ over the set I-time is compensated.
