Olimex Support Forum

Microcontrollers => ESP32 => Topic started by: Stephane80 on November 10, 2019, 07:52:02 pm

Title: ESP32-POE-ISO temperature
Post by: Stephane80 on November 10, 2019, 07:52:02 pm
Hello,
I bought an ESP32-POE-ISO but it seems to me relatively hot with poe.
Can you tell me if it's normal
And what is the normal temperature range of use?
To be able to use it without risk
Thanks in advance for your help.
Best regards, Stephane
Title: Re: ESP32-POE-ISO temperature
Post by: LubOlimex on November 11, 2019, 09:42:16 am
Overall it is normal for this board to get a little hotter than usual electronics but make sure that you are not attempting to draw more than 200mA (300mA if no battery is used) from the 5V line for additional electronics or parts.

Can you tell me which component exactly gets the hottest? Maybe look the component's datasheet and find if it is in the proper range of operation.
Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 11, 2019, 11:55:49 am
Hello ,
I just have a SN65HVD230 (can module) plugged in
like this:
(https://images-na.ssl-images-amazon.com/images/I/41Ib2fB%2BltL.jpg)
I will try to take a thermal image of the esp

Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 11, 2019, 12:29:04 pm
(https://i.imgur.com/sEpGKdy.jpg)
Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 11, 2019, 12:39:50 pm
(https://i.imgur.com/YCwT4Mk.jpg)
Title: Re: ESP32-POE-ISO temperature
Post by: LubOlimex on November 11, 2019, 03:30:06 pm
Hmmm, can you give me some more details about your setup so I can try to repeat same setup here and measure the temperature of few boards.

Did you test only one board or a few boards and all show similar temperatures?

How is the board powered? If it is via PoE can you give me more details about the equipment that feeds the power.

What is the software utilizing - Ethernet, UART, WIFI, other?

Add any other information that would let me test at similar conditions here.

Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 11, 2019, 05:09:58 pm
I do not know if it may matter, but it's exactly a ESP32-POE-ISO-EA version

It's my first esp32 from OLIMEX .I just tested before on TTGO esp32 boards but not POE
The borad is powered via POE ( NETGEAR JGS524PE - 24-Port Gigabit Ethernet PoE Smart Managed Plus Switch )


The can module is connected to +3.3 and GND pins
tx and rx connected to pins 4 and 5

I use the ESP32CAN library to get can messages from other devices in my home
The ESP32 send the infos to a Mosquitto MQTT Broker by LAN
For a JEEDOM home Automation
The ESP32 board can serve a json page with infos too

At this time I use just ethernet and can with TX/RX
Fonctions used :
PubSubClient for mqtt
ESPmDNS
HTTPClient
ArduinoJson for json
ESP32CAN for CAN
ArduinoOTA for OTA (Lan) firmware update

otherwise I would have liked to know:
I can use ESP32-POE-ISO-EA without external antenna connected ?
for now I left it but I do not have the use.

And can you tell me what is the normal operating temperature range of the board ?
I could see comments especially on amazon of POE cards that burned
If it is not safe and there are risks I would go to an external poe splitter or 5v alimentation but it was not the goal of a POE board ;-)




 
Title: Re: ESP32-POE-ISO temperature
Post by: LubOlimex on November 12, 2019, 09:26:31 am
> I could see comments especially on amazon of POE cards that burned

These probably apply for the NON-ISO version - and only when you have both PoE and USB power supplies enabled and connected to the board. The ISO version can't burn in this scenario since the USB and the PoE are galavanically separated.

Edit:

The board should operate between -40 and +85 degrees Celsius and 77 degrees is within the specifications. However, my tests with ESP32-POE-ISO boards went up to 55 degrees Celsius for the same part of the board. I added an expansion board on the UEXT and some Ethernet examples but still this part remained around 55 degrees. I currently have no clear idea what might be causing the higher temperature at your side.

Edit2:

The voltage regulator F0505S-2WR3 should work up to 105 degrees Celsius
Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 12, 2019, 01:54:02 pm
Quote from: LubOlimex on November 12, 2019, 09:26:31 am> I could see comments especially on amazon of POE cards that burned

These probably apply for the NON-ISO version - and only when you have both PoE and USB power supplies enabled and connected to the board. The ISO version can't burn in this scenario since the USB and the PoE are galavanically separated.
It's on product
ESP32-POE-ISO Board for Espressif ESP32 with Wired 100MBit Ethernet with POE isolation https://www.amazon.fr/dp/B07R1ZMSG7/

Comment:
QuoteGreat idea, POE not usable.
So first of all these are a fantastic idea for combining the power of the ESP32 with the simplicity of wired Ethernet. I build devices for family and just plugging in a cable is so much easier for them than configuring wifi. Plus points: 1) The ethernet worked right out of the box using the Olimex sample. The ETH library is compatible with the wifi library so I didn't need to change any client or webserver code. 2) Has the circuitry to program without pressing buttons which is a pain with most of the ESP32 boards. So why only two stars: 1) The first one I received worked beautifully connected by USB for programming and connected by a non-POE Ethernet. Seemed like this was a winner. However when I plugged in an IIC oled it would not program. Same oled does not interfere with a nano. Having to disconnect the oled to reprogram is worse than pressing a button. The replacement unit has the same programming issue - i.e. can't program with the oled attached. I implemented a web updated, problem solved. 2) When I plugged into POE for power, with only a 20ma oled connected it overheated. I plugged it in and checked the website on it and within a minute or so it died. I picked up the board and burnt my finger. The area that was hot was around the 3.3v regulator and coil, not the POE circuit. After this it got hot in seconds even with non-POE Ethernet and USB power; so I'm guessing the POE overloaded something. This is the same POE I'm running cameras and Raspberry Pis on so I am confident in the POE switch. Returned it. The replacement also gets hot around the POE, where the two 220ohm resistors are. These I think is to provide the necessary 250mw minimum to enable POE, if so they need heatsinks. On the replacement unit, when powered by usb the 3.3v regulator is cold. I tried POE for a few seconds and it started getting noticeably warmer on the 3.3v regulator and so did the 5v DC-DC converter and aforementioned resistors. This was with nothing attached. I'm now using an external POE splitter to provide power to the USB; this works well and everything is staying cool. 3) LIPO charger/power - verified that if you lose power, the unit switched to LIPO and carries on without interruption - great. However when you reconnect USB power it reboots. Fortunately this works for me as I only need to detect loss of external power ( thoughtfully provide on GPIO 39)- and save data to SPIFFS. Summary Great idea and i am definitely going to use it, but with an external splitter. Software works out of the box POE is not usable Issues with updating with devices attached but mitigated by web upload. Final thoughts POE need thermal management and isn't easy to squeeze onto a tiny board. Given that external units are around $5 from china I would prefer a straight Ethernet solution.

Quote from: LubOlimex on November 12, 2019, 09:26:31 amEdit:

The board should operate between -40 and +85 degrees Celsius and 77 degrees is within the specifications. However, my tests with ESP32-POE-ISO boards went up to 55 degrees Celsius for the same part of the board. I added an expansion board on the UEXT and some Ethernet examples but still this part remained around 55 degrees. I currently have no clear idea what might be causing the higher temperature at your side.
If it's OK and in specifications
No problem for me.
It's just to be sure that it's safe ;-)
Title: Re: ESP32-POE-ISO temperature
Post by: LubOlimex on November 12, 2019, 02:27:52 pm
Can you tell me what is written on the DCDC1 part of your board? Is it Mornsun or Tesla and what is the model?
Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 12, 2019, 07:00:13 pm
this one ?
(https://imgur.com/1c5wRhL.jpg)
GODSEND F0505S-2WR2 ?

Edit :
not found GODSEND but just see this in morsun F0505S-2WR2 datasheet:
QuoteOperatingTemperature : -40 105
Derating when operating temperature up to85°C,(see Fig.2)
Title: Re: ESP32-POE-ISO temperature
Post by: LubOlimex on November 13, 2019, 04:39:36 pm
I wanted to perform more tests with this specific DC-DC and it seems it also behaves better here - 50 degrees Celsius max. Maybe something in the code or the environment is different. If you want me to perform further analysis or comparison please contact me over the support e-mail - support@olimex.com
Title: Re: ESP32-POE-ISO temperature
Post by: Stephane80 on November 13, 2019, 11:56:34 pm
Hello ,, thank you very much for your help.
I will not make you lose more time.
I will continue the tests and if not I will leave on another solution
with external poe splitter

Best regards , Stephane