Have questions about FETS, transistors, measurement, power supplies, or anything else electrical?

User avatar
By Sani021
#91591 Hi everyone, I'm very new in IOT Industry and I'm trying to find 5v power supply on my ESP8266 wifi module. I believe vin pin is providing 5v power . However for some reason its not working and I don't know whether if the issue is coming from the module I'm using or I'm doing something wrong in terms of coding etc...
FYI when I try to turn on and off the Relay module trough the Blynk app, it turns on but it doesn't execute any sound out Relay which we normally we should hear that little sound. So that makes me think of maybe its not receiving enough power from vin pin which is 5v in this case.
I guess I really need to be clear from vin pin first . So I wonder how can I make sure if the vin pin is faulty or not?
is there any ways to test it without connecting the module to the server to make sure where the issue is coming from?

Thank you everyone.
User avatar
By grinch
#92415 Do you have a multi-meter? If not, they are inexpensive and since one is essential for working with electronic circuits you should really get one. If/when you have one then you can put your multimeter into low voltage sensing (mine is 20V) and the pins across the VIN and GND pins on the esp8266 to get the reading. It also may depend how you are powering up the esp8266 - is it a bare board or integrated into a bigger board like a NodeMCU?