Longo Modbus Products LMP-1.MP2
4 OPERATION
Basic settings can be entered with panel Touch Buttons (TB).
Modes of operation and parameters can be set from any Modbus RTU Master.
It is advised to press touch-buttons respectively with finger not faster than 1 press per second.
Press should be done with whole finger tip. Brief pressing could not activate the action, because of
protection against the noise and other influence.
4.1 Operational modes
LCD Display “stand-by mode”
The display is normally in this mode, if no TB is pressed in last ~5 seconds.
LED intensity is in correlation with Light intensity measurement (more light - brighter, less light -
darker).
Actual room temperature (0.5 °C resolution) is shown on the screen if enabled.
LCD Display “SET mode”
First press on any TB will activate the display to “set mode” and LCD intensity will be put to
maximum. No action regarding the pressed TB is done. Further pressings on any TB will make the
change (bar-graphs) regarding the pressed TB.
Actual temperature set-point (regarding the right bar-graph) is shown on the screen if enabled.
Display will return to “stand-by mode” if touch buttons are not pressed for a while (~5 seconds).
Changing operation modes
Request for switching between CP
normal
and
economic
operating mode is done with lower left and
right TB pressed simultaneously : switch to
economic
mode
Request for switching between CP
on
and
off
operating mode is done with upper
left and right TB
pressed simultaneously : CP switched
off
Confirmation of above requested modes is done by Modbus RTU Master equipment by changing the
appropriate command bit (normal/economic, system on/off).
Normal
This is default mode for MP2 module. The control algorithm is executing regarding the parameters.
Economy
If set, controller will start cooling when room temperature will raise above max. temperature set-
point (SP) and stop when temperature will drop 1 °C below max. temp. SP. On the other hand, when
room temperature fall's below min. temp. SP controller will start heating and stop when
temperature will raise 1 °C above min. temp. SP.
In economic mode “ECO” sign appear on LCD.
Off
In this mode panel sends command to switch off all devices: hot valve and cold valve. Temperature
LCD bar becomes white and “OFF” sign appear on LCD.
CP can be turned off using
System On/Off
command. In this case cool, heat commands are switched
off. Cool and heat commands are also switched off when temperature measured by the panel is
inside temperature dead band values (default dead band is 0.5 °C).
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