Every MLR003R device contains a “Thermoelectic Generator (TEG)” element, that generates electrical energy when there is a temperature difference.
The TEG harvests energy from the temperature difference between the heating flow temperature and the ambient temperature (usually room temperature).
The MLR003R comes with an Aluminum housing as functional part to generate electrical energy.
The actuator has a valve-side temperature sensor to determine the flow pipe temperature and an ambient sensor to determine the ambient temperature which is located away from the flow sensor
There are two compensations performed on the ambient and the flow sensor respectively
The ambient temperature estimation is used to reduce/compensate the temperature difference at the ambient sensor caused by the increased Aluminum housing temperature.
A controllable offset for the flow sensor has been added to compensate for the temperature drop between the hot water and the sensor element located in the actuator’s aluminum valve adapter.
To obtain an estimate of the ambient temperature, the device measures the flow temperature every 5 minutes and performs a moving average across the last 30 minutes.
It then performs the following computation
Orah footnote an.spaceKey MH text Ambient Estimate Calculation id 0cv82peijaks 
The offset value for the Flow Temperature can be set via Downlink on FPORT 0x08
Byte | Uplink in FPORT #1 | Details | Description | |
|---|---|---|---|---|
2 | FSRV | Flow Sensor Raw Value | The uncompensated flow temperature measured at the valve body assembly | |
3 | FTMP | Flow Temperature Value | The compensated flow temperature Flow Sensor Raw Value (FSRV) + OFFSET (set via FPORT 0x08) Default OFFSET = 0 | |
4 | ASRV | Ambient Sensor Raw Value | The uncompensated ambient sensor value | |
5 | ATMP | Ambient Temperature Value | Ambient Temperature calculated from
|
...
The Set Point Value “SPV“ is set by the user through Downlink on FPORT 0x01
The MLR003 either uses the ambient temperature coming from an external sensor (“RT“ in FPORT 0x01 Downlink) or the internal Ambient Temperature (“ATMP“) estimate
FPORT 0x01 Downlink Byte 2 Room Temperature (RT) value | Temperature Value |
|---|---|
0 | Use internal Ambient Temperature (ATMP) estimate |
Room Temperature from external sensor | Use the room temperature value from the external sensor |
| Info |
|---|
If the Set Point Value “SPV“ is different from the Ambient Temperature (“ATMP”) estimate or the Room Temperature (“RT”) value, the PID Control will be activated |
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