Hello, I'm trying to control 48v dc pump with pwm with esp32s3. regardless of pwm signal pump works on and off...
analogWrite(pump, 819) (eg 20% of 4095) pump is on at 100% same at any duty cycle, analogWrite(pump, 0) pump goes off. Any help will be much appreciated!
that it the pump
schematic uploaded
Bad choice for the MOSFET.
You need one that will fully turn on with a 3.3V gate drive.
One that has a maximum Rds(on) of less than 10mΩ @ a Vgs of 3.3V or less with a Vds of 60V or more.
any suggestions?
Can it be a surface mount part?
Can you buy parts from Digi-Key or Mouser?
Yes, I can buy from Digi-Key or combine my order with a friend from mouser... I prefer smd part. This is the pcb and current mosfet
The link to the pump does NOT show what the stall current is for the pump motor. What stall current did your make your design for?
Are you putting the pump down in your well? Are you installing one-way valves in the pipe going to the surface? Otherwise you will have a very long wait for water each time you start the pump. Does your program have a sensor that checks to see when water reaches the surface or are you just watching for water flow with your eyes?
I did not see anything suitable.
You will need to use a standard or 5V logic level MOSFET with a gate driver.
Stall current of the pump - have no idea... may be 15amp I'm guessing. I don't have a sensor, pump is submersed 1.2m deep into the water tank which is filling from another water source, and yes I'm watching the water flow also noise produced by the pump not changing
I have valve but for filling and pressure sensor for water level, pipe is open from pump to surface no obstacles
Do not ever let the pump get out of water, since it is water cooled.
Looks like it was designed for a 24V low current pump but your pump is 48V
Did you design that board?
There may be other issues other than the wrong MOSFET
24v is supplied to pcb because valve operate at 24v and i'm switching the pump power supply (second) 2 sec before starting the pump, 48v is present to the board just for the big shotki
can provide the the full schematic if nesesery
No, mosfet currently does the same thing ON-OFF, I need pwm.
I need pwm.
See post #7
Do you understand?
Have you got the controller gnd connected to the pump supply gnd?
Can you please post a copy of your circuit, a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, power supplies, component names and pin labels.
Tom.... 
Hi, @sirko
As this is a specially built pump/motor for solar operation, NO BATTERY, could your pump have some electronic controls embedded in the pump.
DC brush motor can stall when subjected to low current and if starting after a night time, will be subject to a slow increasing current, the speed control they talk about would possibly be the speed that the embedded motor controller selects to get the motor running and at optimal power.
It may not like PWM supply.
Note this feature;
It appears to have its own speed regulator?
Remember this is an AMAZON site, either to much misleading information or not enough important information.
Tom....
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Do you need help selection the MOSFET and driver?
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Just let me know if you need any further help
