The user has to ensure correct settings. Remember that for the inverters of 3rd generation the relative active power limit is in the range of 2% up to 100%.
**NOTE:** Some users reported that a limit below 20W results in 0W output of the inverter. To reenable the inverter a reboot command was need to be sent, because a new limit with 100% didn't work.
The authentication is only needed if a password was set.
To authenticate from API you have to add the following `JSON` to your request:
```json
{
"auth": <PASSOWRD>
}
```
`<PASSWORD>` is your DTU password in plain text.
As Response you get the following `JSON` if successful:
```json
{
"success": true,
"token": "<TOKEN>"
}
```
Where `<TOKEN>` is a random token with a length of 16 characters.
For all following commands you have only to include the token into your `JSON`:
```json
{
"token": "<TOKEN>"
}
```
ℹ️ Do not pass the plain text password with each command. Authenticate once and then use the token for all following commands. The token expires once the token wasn't sent for 20 minutes.
If the authentication fails or the token is expired you will receive the following `JSON`:
* You can use the mqtt topic `<TOPIC>/devcontrol/<INVERTER_ID>/11` with a number as payload (eg. 300 -> 300 Watt) to set the power limit to the published number in Watt. (In regular cases the inverter will use the new set point within one intervall period; to verify this see next bullet)
* You can check the inverter set point for the power limit control on the topic `<TOPIC>/<INVERTER_NAME_FROM_SETUP>/ch0/PowerLimit` 👆 This value is ALWAYS in percent of the maximum power limit of the inverter. In regular cases this value will be updated within approx. 15 seconds. (depends on request intervall)
* You can monitor the actual AC power by subscribing to the topic `<TOPIC>/<INVERTER_NAME_FROM_SETUP>/ch0/P_AC` 👆 This value is ALWAYS in Watt
To get the information open the URL `/api/record/info` on your AhoyDTU. The information will only be present once the AhoyDTU was able to communicate with an inverter.
1. Get active power limit in percent (`SystemConfigPara = 5 // 0x05`)
2. Get firmware version (`InverterDevInform_All = 1 // 0x01`)
3. Get data (`RealTimeRunData_Debug = 11 // 0x0b`)
With the command get data (`RealTimeRunData_Debug = 11 // 0x0b`) the alarm message counter will be updated. In the initial case then aonther command is queued to get the alarm code (`AlarmData = 17 // 0x11`).
This command (`AlarmData = 17 // 0x11`) will enqued in any operation phase if alarm message counter is raised by one or greater compared to the last request with command get data (`RealTimeRunData_Debug = 11 // 0x0b`)
In case all commands are processed (`_commandQueue.empty() == true`) then as a default command the get data (`RealTimeRunData_Debug = 11 // 0x0b`) will be enqueued.
In case of a accepted change in power limit the command get active power limit in percent (`SystemConfigPara = 5 // 0x05`) will be enqueued. The acceptance is checked by the reponse packets on the devive control commands (tx id 0x51 --> rx id 0xD1) if in byte 12 the requested sub-command (eg. power limit) is present.
In order to display the sunrise and sunset on the start page, the location coordinates (latitude and longitude) must be set in decimal in the setup under Sunrise & Sunset. If the coordinates are set, the current sunrise and sunset are calculated and displayed daily.
If this is set, you can also tick "disable night communication", then sending to the inverter is switched off outside of the day (i.e. at night), this avoids unnecessary communication attempts and thus also the incrementing of "RX no anwser".
Here you can get easy your GeoLocation: [https://www.mapsdirections.info/en/gps-coordinates.html](https://www.mapsdirections.info/en/gps-coordinates.html)
### Commands and informations
Turn On - turns on the inverter/feeder (LED flashes green if there is no error)
Turn Off - switches off the inverter/feeder (LED flashes fast red), can be switched on again with Turn On or by disconnecting and reconnecting the DC voltage
Restart - restarts the microcontroller in the inverter, which deletes the error memory and the YieldDay values, feed-in stops briefly and starts with the last persistent limit
Send Power Limit:
- A limitation of the AC power can be sent in relative (in %) or in absolute (Watt).
- It can be set to a different value non-persistently (temporarily) at any time (regardless of what you have set for persistent), this should be normal in order to limit the power (zero feed/battery control) and does not damage the EEPROM in the WR either.
- With persistent you send a saving limit (only use it seldom, otherwise the EEPROM in the HM can break!), This is then used as the next switch-on limit when DC comes on, i.e. when the sun comes up early or the WR on batteries is switched on the limit is applied immediately when sending, like any other, but it is stored in the EEPROM of the WR.
- A persistent limit is only needed if you want to throttle your inverter permanently or you can use it to set a start value on the battery, which is then always the switch-on limit when switching on, otherwise it would ramp up to 100% without regulation, which is continuous load is not healthy.
- You can set a new limit in the turn-off state, which is then used for on (switching on again), otherwise the last limit from before the turn-off is used, but of course this only applies if DC voltage is applied the whole time.
- If the DC voltage is missing for a few seconds, the microcontroller in the inverter goes off and forgets everything that was temporary/non-persistent in the RAM: YieldDay, error memory, non-persistent limit.
Here are the [latest stable releases](https://github.com/lumapu/ahoy/releases/) and [latest development builds](https://fw.ahoydtu.de/dev) available for download.
As soon as you have downloaded the firmware package, unzip it. On the WebUI, navigate to Update and press on select firmware file.
From the unzipped files, select the right .bin file for your hardware and needs.
- If you use an ESP8266, select the file ending with esp8266.bin
- If you use an ESP8266 with prometheus, select the file ending with esp8266_prometheus.bin
- If you use an ESP32, select the file ending with esp32.bin
- If you use an ESP32 with prometheus, select the file ending with esp32_prometheus.bin
Note: if you want to use prometheus, the usage of an ESP32 is recommended, since the ESP8266 is at its performance limits and therefore can cause stability issues.
After selecting the right firmware file, press update. Your AHOY-DTU will now install the new firmware and reboot.
- AhoyDTU supports MI type inverters as well, since dev. version 0.5.70.
- MI inverters are known to be delivered with two different generations of firmwares: inverters with serial numbers 10x2 already use the 3rd generation protocol and behave just like the newer HM models, *the follwoing remarks do not apply to these*.
- Older MI inverters (#sn 10x1) use a different rf protocol and thus do not deliver exactly the same data. E.g. the AC power value will therefore be calculated by AhoyDTU itself, while other values might not be available at all.
- Single and dual channel 2nd gen. devices seem not to accept power limiting commands at all, the lower limit for 4-channel MI is 10% (instead of 2% for newer models)
- 4-channel MI type inverters might work, but code still is untested.
