# Trouble with TX4 and temp sensors

**URL:** <https://community.openenergymonitor.org/t/trouble-with-tx4-and-temp-sensors/26115>\
**Category:** emonTx\
**Created:** [8 May 2024 21:17 UTC](https://community.openenergymonitor.org/t/trouble-with-tx4-and-temp-sensors/26115 "2024-05-08T21:17:14Z")\
**Posts on this page:** 1\
**Showing post:** 14

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**Author:** ![TrystanLea](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/trystanlea/32/31_2.png) [@TrystanLea](https://community.openenergymonitor.org/u/TrystanLea)\
**Post date:** [13 May 2024 17:09 UTC](https://community.openenergymonitor.org/t/trouble-with-tx4-and-temp-sensors/26115/14 "2024-05-13T17:09:20Z")

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> [@whitecitadel](#):
>
> In my case it’s an EmonTX4 but I assume the same restrictions?

> [@whitecitadel](#):
>
> it’s confusing as the emontx had all these ports… but it was not immediately clear you can’t use temp sensors.

There is emonTx4, emonPi2 and emonTx5 firmware that supports temperature sensing running on the AVR-DB microcontroller (with up to 6CT sensors and single phase only). The option that supports temperature sensing uses the earlier emonLibCM library. The important thing to note here is that temperature sensing is supported by degrading the performance of the electricity monitoring very slightly and it does seem to be quite a small impact, see my post about this at the time here [EmonTx4 DS18B20 Temperature sensing & firmware release 1.5.7 - #3 by TrystanLea](https://community.openenergymonitor.org/t/emontx4-ds18b20-temperature-sensing-firmware-release-1-5-7/23496/3)

> [@EmonTx4 DS18B20 Temperature sensing & firmware release 1.5.7](https://community.openenergymonitor.org/t/emontx4-ds18b20-temperature-sensing-firmware-release-1-5-7/23496/3):
>
> a potential 0.04-0.07% error in the context of a hardware component tolerance error of ~1.2% is not that much,

While I’m quite happy with the approach I took there, Robert and other’s who I consulted on this were less happy with the approach I took, I completely accept it’s an imperfect and not entirely satisfactory solution and don’t wish to argue that it is anything else.

So with Robert developing the new emonLibDB library to support up to 12 CT sensors and 3 phase monitoring we decided against trying to apply a similar approach with this library, there is more going on in the new library as well.

In summary, there will be 3 new firmwares available for the emonTx4, emonTx5 and emonPi2

- [emon\_CM\_6CT\_temperature](https://github.com/openenergymonitor/avrdb_firmware/tree/master/emon_CM_6CT_temperature) uses the emonLibCM library and therefore supports temperature sensing with the caveat above.

- [emon\_DB\_6CT](https://github.com/openenergymonitor/avrdb_firmware/tree/master/emon_DB_6CT) uses the emonLibDB library and therefore does not support temperature sensing on the microcontroller core.

- [emon\_DB\_12CT](https://github.com/openenergymonitor/avrdb_firmware/tree/master/emon_DB_12CT) uses the emonLibDB library and therefore does not support temperature sensing on the microcontroller core.

When emon\_DB\_6CT and emon\_DB\_12CT are used in the emonPi2 configuration (with a RaspberryPi inside the case) temperature sensing is supported via the RaspberryPi itself 🙂

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_[View the full topic](https://community.openenergymonitor.org/t/trouble-with-tx4-and-temp-sensors/26115)._
