Hey there!
I have a project which consists of ESP32, 5 Capacitive moisture sensors, 2x2 Relays, 1xDHT22, 1xPhotoResistor, 1x H20 Pump 12v 0.6A, 1xCooling fan 5v, 0.1A, 1x DS18B20 temp sensor. i am planing to put couple of more things to the 2x slots in the other Relay and perhaps couple of more sensors.
I am currently only powering the stuff from the 5V pin from the board, and have external supply to the 1 of the Relays.
I have made a small branching PCB so it will be more easier to draw the power for the sensors.
First what is the best option to use outside power source 5v with regulator and GRN thru the GRN pin on the ESP32, or just use the power supply from the board?
I did initially separate power supply but it appears, my sensors didnt work properly. I believe should have reset the power supply each time when I uploaded the new code.
Appreciate your comments and suggestions!
Start to calculate how much amps your powersuply must provide to get e everything running. After that I usually choose something that can provide at least twice as much.
I have loads of 1amp and 2 amp 5v phonechargers laying around. I guess a 2 amp will do. To be found cheap on those outdoor markets. Nor sure how you call them here the call them "rubbish markets" lol.
Don't guess. Measure, look up specs, calculate, and know.
The list of parts adds up to a bit less than 1A (the relays are not specified but normally no more than 50 mA each), so a 2A 12V supply would do nicely.
Many of my projects also require 12V (pumps etc), 5V (certain sensors - trying to avoid this part) and 3.3V (ESP8266, other sensors). Always tricky. I normally use a 12V supply that's got enough grunt to power it all; 2A 12V-5V buck converter; 3.3V linear regulator powered by the 5V supply to produce a nice and clean 3.3V for the processor and so.
I don't use relays, preferring to switch DC loads using MOSFETs.
You would need the 5V supply for the relays and the fan; drawing 300-400 mA or so. A 2A buck converter will handle this nicely.
Thank you to ALL for chipping in and giving your valuable opinion and output. Beer is on me(ID required :)). I did calculate the stuff, and I thought 1A, will do, but now will do the double, hopefully not the trouble.
So, I will publish my# for those browsing the subject in the future what I have as a power draw. (T = Total)
5x CMS v1.2 ph2.0-3P each 5mA = T25mA
1 AM2303 a.k.a DHT22 @ 2mA with 5V input = T2mA
1 double Relay, 2 coils, both are in use. As you guys said, 50mA each. = T100mA
1 Fan 5V, 0.1A = T100mA
1 Pump, 5V boost step up converter used to get 12V (gets really hot in long runs) 0.6A = T600mA
1 PhotoResistor analog, power draw is insignificant, but I will stay generous and put 1mA.
So at this setup, the TA= 828mA, or 1A, should be enough, but as all the respondents suggested I will use the usb 2.1/5VA USB converter.
wvmarle suggest a 12v power supply with a step down, if you still need to get your power supply that's poetically the best thing to do. I don't have much intellects running requiring 12v so usb works for me.
If you want to get 12V 600 mA out of a boost converter, you have to input about 1.6A at the 5V side (assuming 90% efficiency). Add the rest and you're at almost 2A at 5V. You always have to downrate power supplies, so a 5V 3-4A power supply would be needed.
Better use a 12V supply and step down the voltage. Less current on the 5V side.
Hi,
Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?
Your picture relays (pun not intended) very little about how your circuit is configured?
Do you have a DMM?
Thanks.. Tom.. 
