Power resume after power failure need some help

claustro

Hi guys . I have a C-bot :

Board: Duet 2 WiFi (2WiFi)
Firmware: RepRapFirmware for Duet 2 WiFi/Ethernet 3.4.6 (2023-07-21)
Duet WiFi Server Version: 1.27

Z-axis is driven with 3 screws and one single motor. My zero on z axis is done by bl.touch

When I am thinking about zeroing the z-axis after power failure I am thinking at 2 ideas.

I make zero on the bed using bl-touch probing on a far angle so , ideally , the already printed material isn't caught in the printer axis.
in this case resurrect-prologue.g could be something like this


M116 ; wait for temperatures
G28 X Y ; home X and Y, hope that Z hasn't moved
G90              ; absolute positioning
G1 X20  Y20 F6000 ; go to first probe point
G30              ; home Z by probing the bed
M83 ; relative extrusion
G1 E5 F3600 ; undo the retraction that was done in the M911 power fail script

Do you think it will work?

make zero on the other side of the z axis using a mechanical or optical endstop at the and of lead screw . The 3 screws are moved together so no need to level the bed. In this case I should use this zero sensor only for power failure.
In this case where I should hang up the sensor ?
Can you give me some suggestions?

Thank you