I will likely buy a High Frequency Pulse Width Modulator (PWM). Any suggestions on PWM specs and settings? And specific PWM suggestions? I just want a PWM with a rotary knob, as distinct from a Raspberry computer.
Here are some specs for the pump that I wish to control:
Voltage, frequency and pulse shape are ‘as provided by mains voltage’ i.e. for US/Canada 120V 60Hz full sinewave. The pump (as per Olab description) includes an integrated rectifier which feeds only the ‘positive’ half of the sinewave to the coil. There is no indication of the characteristics of this rectifier, or of the mechanical circuit in the pump (which is likely to be the limiting factor in terms of frequency response).
Other pump specs:
ED: 2/1 minute
The 230/240 volt version of the pump is 35 Watts.
My Lelit E espresso machine is a 110v machine.
By my math, the amperage is 0.1489.
Calculated as X amps X 235 volts = 35 watts
35 watts / 235 volts = 0.1489 amps
Hope you can help, as soon as convenient.