gefran 3850T Use And Installation Manual page 90

4. CONFIGURATION
Valve + Ratio PID
The number of the PID to be set is displayed at the top of
the screen and can be changed using the - and + keys.
Turn the PID on and off with the EN button. The key turns
green when the PID is enabled.
The diagrams can be interpreted as follows:
• the arrows that enter the PID box identify the input vari-
ables that must be processed or compared by the PID;
• the arrows that exit the PID box identify machine or
process control signals that were processed by the
PID;
• the arrow that enters the valve symbol identifies the
valve motor control signal;
• the box marked with an X indicates that process that
forces a fixed regulation ratio between two process
values.
The values shown in this page cannot be edited, while the
names of the variables associated with some parameters
88
Valve PID
Ratio PID
can be edited.
The parameters are:
• PVx: the name and current value of the input process
variable.
• SP: the value to be reached or maintained (read only).
• OUTP: the name and value of the output variable,
or power distributed, that varies from -100.0% to
+100.0% for PID hot/cold.
• HEAT: the name and value of the output heating Bool-
ean variable. The default outputs are Digital Outputs
01, 02, 03, etc.
• COOL: the name and value of the output cooling Bool-
ean variable.
• Fb: the name and value of valve feedback with retro-
action. Parameter FB is fixed, between 0.0 and 100.0
(with one decimal point).
• RATIO: are the name and value of the fixed control
ratio between two process values.
The number and type of available variables depends on the
type of PID.
The variable list can be scrolled using the buttons on the
right of the display:
and move the list by 3 variables;
and move the list by 10 variables;
You can also jump directly to specific points in the list by
touching the alphabetic directory keys. When the key is
marked with two characters or digits (for example, A0, B1,
etc.) quickly touch the key twice to jump to the second
character. The sp button means "space".
Once you see the variable, touch it to select it.
The CLEAR button deletes any variable in the field and
closes the window; the field becomes empty.
Touching the X at the top right corner closes the window
without confirming any selections.
The Sim button lets you open simulator functions.
The simulation page is divided into 3 sections: Regulation,
Valve and CT (current transformer). Use the enable sim
button to enable or disable the simulator and use the PID
no. + and - buttons to switch from one PID to another. The
enable sim button enables the simulator in GF_eXpress
from the outside, which allows you to force DI/DO
The Regulation section lets you simulate a process vari-
able (simulated input) according to the associated heating
or cooling function.
The noise field (in points) lets you set white noise to disturb
simulation. The maximum range points can be set as the
80703B_MHW_2850T/3850T_02-2019_ENG