@dc42 0.9 degrees. These are Wantai motors, 2.4A with a fairly low inductance
I did not try this with a 30mm fan, but with the 4010 fan turned off, the repeatability was better. Although accuracy of 0.02 suits me, if only the accuracy of calibration affects only the first layer. If this affects print quality further layers, of course I will fight for better accuracy.

Honestly, I don’t know what can be improved in my mechanics. I installed hivin rails and haydn magnetic rods, optical stops.
the bed is a plate on the entire area of the delta .. all that comes to mind is to anchor it to the floor)

@dc42 I'll see. what about accuracy?

@dc42 thanks. I put a 30mm maglev fan and everything became fine, but another problem appeared) In the previous assembly, the yellow LED on top of it was always on during operation. He blinked randomly. Now it does not burn at all, although the heating is on and everything is printing.
By the way, I was looking for information on the network, but I could not find it - what is the error of the strain gauge? I have repeatability of the results within 0.02 mm (but I want to note that I use a klipper, although the board and the effector are a duet)

It would be more maintainable to make terminal blocks below not only for the heater, but also for fans and a thermistor. Sometimes they have to be changed and then you have two ways - to compress the molex again or to cut and twist the wire. Easier to tighten into the block

Separately, I want to note that the molex in the lower part on the thermistor and on the fans is a terrible decision. Replacing a thermistor or fan turns into a headache

@Danal In this case, the Chinese cheap fan should have influenced in the same way. It vibrated 10 times stronger, but the sensor was not triggered

I know that everything works without a fan) I wonder why it does not work with it?)

Yesterday I acquired this beautiful effector, dabbled with calibration all evening, but I had a regular Chinese fan 4010 to blow the radiator, which was very noisy and vibrated. Today I changed it to Sunon. everything became noticeably quieter, however, with the connected fan, the operation sensor is constantly on. I can calibrate the delta only with the fan turned off. Why and how to fix it?

After calibrating g32, the m500 command is not displayed on the console. (but save all values) The loading process is strange. It shows immediately 100 percent and the window hangs waiting until the download actually completes