tjheikki Can be flashed with Tasmota or something to do anything a programmable device can. For that need an USB UART, some wire and reading the firmware's documentation. In Tasmota, the command "SwitchMode 13" makes the button turn relay on until delay and "PulseTime 50" sets the timer to 5.0 seconds.

tjheikki Excellent for 12428 - just the right size more diameter, much wider to allow faster turns and less sticking to branches, rounder "corners" also help avoiding tripping over. Very sturdy, have taken 3S brushless torque without problems. Need some washers in front hubs or extenders, washers have been working fine for me.

tjheikki Atleast no obvious way to change frequency, there is only one button for choosing display mode. May or may not be possible to change easy inside, haven't opened yet (even if I tend to lose screws of devices with other packing material:).

tjheikki Apparently it is only a battery powered dimmer controller, not connected to mains power thus not requiring such certifications. This question would be relevant to the actual dimmer part (if mains powered instead of low voltage DC), I'd expect to find a CE (China Export) sign there:)

tjheikki At least not the one I got, 3.89-12.31 I measured as the no-load range.

tjheikki Two of the pics directly show "2 hp" in the american units, and typing "5 hp in kW" into Chrome or Google would tell 3.7285 kilowatt, rather much more than the 1.5 kW mentioned on the title line, thus the answer is a pretty confident "No". I doubt a 1.5 kW compressor would start with this, as they need more for starting.

tjheikki Yep oil fillable and feel like holds it, and does fit 12428, if some washers etc spacers used at top.

tjheikki Not an exact match but does fit. It is a couple of mm shorter than the stock one, so only one screw properly fits. I have matched the hole further from the arm, the other tightened only partly on the servo but this setup seems sturdy enough, as the holder clamps it pretty steady.