Battery state of charge sensor using ESphome

I want to create a 24V lead acid battery charging sensor for my UPS, using either esp32 or esp8266 boards. What parts are required for it.

What is the maximum charge and discharge current?

If it is less than 3.2A you could use this:

This one can do up to 15A

Those are 140AH batteries image

That’s the battery capacity. Which does not answer my question.

I think it doesn’t exceed 15A @24V I haven’t used the UPS since 4 years, these batteries will be new. So this is just an estimation from memory.
On the other hand discharging current can be around 20A maximum.

In that case probably the best solution would be this:

Make sure you select a model that has an external current shunt that can handle more than 20A, e.g. the 50A version here:

You will also need an RS485 to 3.3V TTL converter to connect this to the ESP. e.g.

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Can I use any of these with LCD display, even though these are not mentioned in esphome.

or should I go with PZEM-017+50A+USB package
https://www.daraz.pk/products/consumption-meter-peacefair-pzem-017-dc-voltage-current-power-energy-communication-module-i210628199-s1417658397.html?

or
PZEM-003 DC + USB to TTL

or should I get one without USB to TTL buy separate TTL to Rs485?

https://www.daraz.pk/products/ttl-rs485-avr-33v50v-i276448299-s1492911506.html?spm=a2a0e.searchlist.list.25.21696a625XdyId&search=1

Sure, if you can write your own custom component for ESPHome.

ESPHome does not support talking to the PZEM via USB. Only serial. So the USB adaptor would be no use to you and just added expense.

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[quote=“tom_l, post:8, topic:415774, full:true”]

So I should buy either PZEM-003

or
https://www.daraz.pk/products/consumption-meter-peacefair-pzem-017-dc-voltage-current-power-energy-communication-module-i210628199-s1417658397.html
most likely pzem-017 due to its higher range of 0-50A.

and a separate https://www.daraz.pk/products/ttl-rs485-avr-33v50v-i276448299-s1492911506.html?spm=a2a0e.searchlist.list.25.21696a625XdyId&search=1

Then no you cant use those LCDs.

The PZEM-003 is only 10A, so not enough for your expected 20A load current. You want the PZEM-017+50A shunt.

And yes that RS485 converter module.

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