I'm controlling an big dc electromagnet, it is 17 ohms.For the voltage control i using Gammon's circuit to control it with pwm.I using 125Hz Pwm to make a high resolution control.I Pwm's period is 8000 Microseconds so if i give pin high time for 4000uS electromagnet have half of the input voltage.My ınput voltage is 12 volts but my multimeter measures 10 volts when duty cycle is full.It's okey, no problem.
As you know, Pwm making on (10 volts) and off (0 volts) but multimeter measures like analog voltage like if duty cycle is %10 voltage is 1V %30 3V .. etc.It is well too no problem.
I have to measure current of electromagnet for full control of magnet, just voltage control is not enough because e.magnet is heating, it makes resistance rising, current reducing, when current reduced electromagnetic force is reducing.But if i measure it's current i will adjust duty cycle depending on current.
Electromagnet's maximum current is 600mA(approsimately)
Electromagnet's minimum current is 15mA(approsimately)
One step up of duty cycle is 10v/8000= 1.25mV
One step up of duty cycle makes current diference is 65uA
Can you please recommend me a sensor?Can INA226 module (Datasheet) do this?Or can you guide me please?