Longo programmable controller LPC-2.DP1
measured by the panel is inside temperature dead band values (default dead band is 0.5 °C).
Error
In case of CP internal on communication fault, “ERR” sign appear on LCD.
Set
When any of four buttons is pressed more than certain time, “SET” sign appear on LCD and buttons
functioning is enabled. After “SET” sign is off, push buttons functions are disabled.
3.2 Functions
PI controller
Output variable range is 0 to 10000 (0..100%) in heating and/or cooling mode respectively .
Values are used for analog/digital (0..100% / I.,II.,III. speed ) output reference for the fan speed
and/or the output for the heat/cool actuator (0..100% / On-Off valve).
The dynamics of PI calculation is defined by P& I parameters.
Example:
If proportional – P parameter (default = 25) is set to 1 and difference between measured
temperature and temperature set point is changed to +1 °C, the PI output value will change from
example 5000 to 5100. On the other hand if the difference is changed to -1 °C, PI output value will
change from example 5000 to 4900.
If integral – I parameter (default = 5) is set to 1 and difference between measured temperature and
temperature set point is +1 °C, the PI output value will increase every second by 1. On the other
hand if the difference is -1 °C, the PI output value will decrease every second by 1.
2/4 pipe system selection
While 4-pipe (factory default) system active, controller will activate hot water actuator when
heating is required and cool water actuator when cooling is required.
In case 2-pipe system is active, hot water actuator will be operated regardless whether heating or
cooling is needed. Mode of operation (closing, opening) is dependent on
Winter/Summer
parameter.
Example:
System selected is 2-pipe , summer mode active and SP is lower than room temperature. CP will
start cooling with activating heat valve. In 2-pipe system cool valve is always inactive.
Frost protection
Function activates heat command when room temperature measured by the panel drops below 7 °C.
This function has priority over all control panel integrated functions.
Window open
Panel will operate in special mode if opened window and opened balcony door are detected. This
function is enabled by enabling parameters
Balcony door En.
or
Window En.
When this function is
active and one of parameters
Window
or
Balcony Door
commands is active, fan will stop and valves
for heating and cooling will close (delay of 1 minute is add with Balcony door command).
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