I want to control a small pump for watering my plants from an ESP32. I try to battery power the device, so the voltage is either 3,3V or something between 2.9 and 4.2 volts from a lithium-ion battery. How will the relay perform at these voltages?
I connect the relay to my bench power supply and test: The control signal is not 5v, but has to be 0v (ground). Weird, but ok, I just need to know.
5 volts works as expected, but the power consumption is alreay 72mA (360 mW). This is a lot. There are So I reduce to the voltage and at 3.5 volts it stops to be reliable.
|3.3V||No||44||Not at all|
This means it will work only when the batteries are not discharged too much. And the 3.3 volts from the ESP are not possible at all.