mirror of
https://github.com/nekorevend/esphome-emporia-vue-utility.git
synced 2026-01-08 20:40:39 -07:00
4119104259
* Docs: overhaul of all the docs. The main README.md is much leaner and broke off the steps. Added a FAQ, greatly expanded the Wiring section. * Fixed FAQ link * Fixed some relative links * Fixed another link * Minor * Reverted title of the Project - didn't mean to do that.
151 lines
7.0 KiB
Markdown
151 lines
7.0 KiB
Markdown
# Meter Reading
|
|
|
|
There are at least two known response payloads sent by the MGM111 chip. MGM Firmware version 2 sends a 152 byte payload while version 7 sends a 44 byte payload. Check the section below relevant to your version.
|
|
|
|
## Payload for Version 2
|
|
|
|
The meter reading response contains 152 bytes of payload, most of which seem to always be zeros. The fields in the payload have
|
|
a mix of sizes and just to make things more confusing, the use of LSB / MSB byte ordering is inconsistent.
|
|
The below table details the payload format that's been reversed engineered so far.
|
|
Blank cells have never been seen to be anything other than zero. Note the table is zero-indexed (starts at byte zero, not byte 1)
|
|
|
|
<table style="width:20%">
|
|
<tr> <td></td>
|
|
<th align="center"><img width="50" height="1">0<img width="50" height="1"></th>
|
|
<th align="center"><img width="50" height="1">1<img width="50" height="1"></th>
|
|
<th align="center"><img width="50" height="1">2<img width="50" height="1"></th>
|
|
<th align="center"><img width="50" height="1">3<img width="50" height="1"></th>
|
|
</tr>
|
|
<tr> <th>0</th> <td colspan=4></td></tr>
|
|
<tr> <th>4</th> <td colspan=4 align="center">EnergyVal</td></tr>
|
|
<tr> <th>...</th> <td colspan=4></td></tr>
|
|
<tr> <th>44</th> <td colspan=3></td><td align="center">MeterDiv</td></tr>
|
|
<tr> <th>48</th> <td colspan=2></td><td colspan=2 align="center">EnergyCostUnit</td></tr>
|
|
<tr> <th>52</th> <td colspan=2 align="center">Unknown 1</td><td colspan=2></td></tr>
|
|
<tr> <th>56</th> <td></td><td colspan=3 align="center">PowerVal</td></tr>
|
|
<tr> <th>...</th> <td colspan=4></td></tr>
|
|
<tr> <th>148</th> <td colspan=4 align="center">MeterTS</td></tr>
|
|
</table>
|
|
|
|
### Known Fields
|
|
|
|
#### EnergyVal
|
|
|
|
Bytes 4 to 8, 32 bit int, unknown if signed, MSB
|
|
|
|
Energy Meter totalizer in watts, in other words, cumulative watt-hours consumed. Unknown when this value resets to zero,
|
|
might reset monthly or on start of new billing cycle.
|
|
|
|
Sometimes, an invalid number greater than `0x00400000` is returned, it is not understood when or why this happens.
|
|
|
|
#### MeterDiv
|
|
|
|
At least byte 47, maybe as large as bytes 44 to 47
|
|
|
|
Some meters report values not in watts and watt hours but in a multiple of those values. `EnergyVal` and `PowerVal` should
|
|
be divided by `MeterDiv` to determine the real value. Usually this is 1, but have also seen a value of 3.
|
|
|
|
#### EnergyCostUnit
|
|
|
|
Bytes 50 and 51 MSB(?)
|
|
|
|
Usually `0x03E8`, which is 1000. Theorized to be how many `EvergyVal` units per "cost unit" (a value we don't appear to have).
|
|
Since people are typically charged per kWh, this value is typically 1000.
|
|
|
|
This value is not currently used in the code
|
|
|
|
#### PowerVal
|
|
|
|
Bytes 57 to 59 (24 bit signed int, MSB)
|
|
|
|
The power being consumed at the moment in Watts. If you have a grid-tie solar / wind / battery system, then this value can go negative.
|
|
Negative values are returned in 1's complement notation (if left most bit is 1, then flip all the bits then multiply by -1)
|
|
|
|
"Data Missing" / "Unknown" is denoted as max negative, `0x800000`
|
|
|
|
#### MeterTS
|
|
|
|
Bytes 148 to 151 (32 bit unsigned int, LSB)
|
|
|
|
Number of milliseconds since an unknown event. Could be time since `EnergyVal` was reset, or could just be a free-running timer.
|
|
Will roll over every 49 days.
|
|
|
|
Only reported as a debugging value, not used in calculations.
|
|
|
|
#### Unknown 1
|
|
|
|
Bytes 52 and 53
|
|
|
|
The meaning of the values in these fields is completely unknown. They appear to be static for each meter. Some of the observed values from users include:
|
|
```
|
|
fbfb
|
|
2c2b
|
|
3133
|
|
```
|
|
Random uneducated guess is that this is a bit field with flags about the meter configuration.
|
|
|
|
## Payload for Version 7
|
|
|
|
The meter reading response contains 44 bytes of payload, most of which seem to always be zeros. The table below details the payload format that's been reversed engineered so far.
|
|
Blank cells have never been seen to be anything other than zero. Some cells have hex codes that I have never seen change, but might differ for you. Note the table is zero-indexed (starts at byte zero, not byte 1).
|
|
|
|
<table style="width:80%">
|
|
<tr> <td></td>
|
|
<th align="center"><img width="50" height="1">0<img width="50" height="1"></th>
|
|
<th align="center"><img width="50" height="1">1<img width="50" height="1"></th>
|
|
<th align="center"><img width="50" height="1">2<img width="50" height="1"></th>
|
|
<th align="center"><img width="50" height="1">3<img width="50" height="1"></th>
|
|
</tr>
|
|
<tr> <th>0</th> <td colspan=1 align="center">0x18</td><td colspan=1 align="center">Incrementor</td><td colspan=1 align="center">0x01</td><td colspan=1></tr>
|
|
<tr> <th>4</th> <td colspan=2></td><td colspan=1 align="center">0x25</td><td colspan=1 align="center">ImportWh~</td></tr>
|
|
<tr> <th>8</th> <td colspan=3 align="center">~ImportWh</td><td colspan=1></td></tr>
|
|
<tr> <th>12</th> <td colspan=1></td><td colspan=1 align="center">0x01</td><td colspan=2></td></tr>
|
|
<tr> <th>16</th> <td colspan=1 align="center">0x25</td><td colspan=3 align="center">ExportWh~</td></tr>
|
|
<tr> <th>20</th> <td colspan=1 align="center">~ExportWh</td><td colspan=2></td><td colspan=1 align="center">0x01</td></tr>
|
|
<tr> <th>24</th> <td colspan=1 align="center">0x03</td><td colspan=1></td><td colspan=1 align="center">0x22</td><td colspan=1 align="center">MeterDiv</td></tr>
|
|
<tr> <th>28</th> <td colspan=2></td><td colspan=1 align="center">0x02</td><td colspan=1 align="center">0x03</td></tr>
|
|
<tr> <th>32</th> <td colspan=1></td><td colspan=1 align="center">0x22</td><td colspan=2 align="center">EnergyCostUnit</td></tr>
|
|
<tr> <th>36</th> <td colspan=1></td><td colspan=1></td><td colspan=1 align="center">0x04</td><td colspan=1></td></tr>
|
|
<tr> <th>40</th> <td colspan=1 align="center">0x2A</td><td colspan=3 align="center">PowerVal</td></tr>
|
|
</table>
|
|
|
|
### Known Fields
|
|
|
|
#### ImportWh
|
|
|
|
Bytes 7 to 10, (32 bit int, probably unsigned, LSB)
|
|
|
|
Cumulative watt-hours consumed from the grid. Unknown when the value resets, but probably never resets since ESP32 never sends a clock sync to the MGM111 so it likely just rolls over.
|
|
|
|
#### ExportWh
|
|
|
|
Bytes 17 to 20, (32 bit int, probably unsigned, LSB)
|
|
|
|
Cumulative watt-hours sent to the grid. Unknown when the value resets, but probably never resets since ESP32 never sends a clock sync to the MGM111 so it likely just rolls over.
|
|
|
|
#### MeterDiv
|
|
|
|
Byte 27
|
|
|
|
Used in conjunction with `EnergyCostUnit` and `PowerVal` to calculate the actual wattage.
|
|
|
|
#### EnergyCostUnit
|
|
|
|
Bytes 34 and 35 LSB
|
|
|
|
Usually `0xE803`, which is `0x03E8` = `1000`. Continuing the V2 theorization that this is the number of watt-hour units per "cost unit".
|
|
Since people are typically charged per kWh, this value is typically 1000.
|
|
|
|
#### PowerVal
|
|
|
|
Bytes 41 and 43 (24 bit signed int, LSB)
|
|
|
|
The power being sent or consumed at this moment. The actual wattage is calculated with the formula:
|
|
|
|
`Watts = PowerVal * MeterDiv / (EnergyCostUnit / 1000)`
|
|
|
|
#### Incrementor
|
|
|
|
Byte 1 (8 bit unsigned int)
|
|
|
|
This just increments by 1 on each reading and rolls over. |