Every MLR003R MLR003 device contains a “Thermoelectic Generator (TEG)” element, that which 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 MLR003 comes with an Aluminum aluminium housing as a 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 pipe. Because the ambient sensor is surrounded by the aluminium housing and is still very close to the radiator, when the radiator is heating, the value measured by the ambient sensor is higher than the actual room temperature. Thus an algorithm is applied to estimate the room temperature.
A controllable offset for the flow sensor has been added is available to compensate for the temperature drop between the hot water and the sensor element located in the actuator’s aluminum valve adapterdevices which are mounted above exposed hot water pipes. It can be set by sending an FPORT 0x08 Downlink.
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 assemblyside | |
3 | FTMP | Flow Temperature Value | The compensated flow temperature flow moving average, with offset applied Moving Average of 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
|
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The Set Point Value “SPV“ is set by the user through Downlink on FPORT 0x01
The MLR003 MLR003R uses 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 |
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In order to achieve a Set Point Value
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(SPV) Ambient Temperature, the device applies a PID control algorithm.
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