BTT SFS v2.0

Sovol Zero
1

Hello all. First post on here.

Fitted a BTT smart filament switch/sensor to the Zero, but noted whilst I was in the process of doing so that I was unable to find dedicated info regarding the Zero on the subject, so thought I’d post this here incase it comes in useful for anyone else considering doing so. Apologies if I’ve overlooked/missed information already available.

Printed this bracket for fitting the sensor.

Wiring wise, the switch connector, I placed in the socket where the exisiting filament switch was plugged in, and the motion sensor I used the socket next to that, (which is unused), for the motion sensor plug.

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The blue & red wires from the new sensor go to the existing filament switch socket, the black & green to the socket to its right.

This is the sensor/switch fitted.

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Changes I made to printer.cfg in order to get it working. This may still need a tad of tweaking, but it appears to be working fine currently. I based this on the example configuration from BTT.

# Start of filament sensor block

[pause_resume]
recover_velocity: 50.0

[filament_switch_sensor filament_sensor]
pause_on_runout: False
switch_pin: PB2
runout_gcode:
	PAUSE
	M117 SFS-S Empty
	#CONTINUE_PRINT_D D={200}
insert_gcode:
	M117 SFS-S Inserted

[filament_motion_sensor encoder_sensor]
pause_on_runout: False
switch_pin: PE7
detection_length: 4.99 
extruder: extruder
runout_gcode:
	PAUSE
	M117 SFS-M Static
insert_gcode:
	M117 SFS-M Moving

# End of filament sensor block
5 Likes
2

Nicely done! Thanks for posting this to help those who may want to add the BTT run out sensor. It’s in my Amazon Saved For Later list, but I’d get it to use at the top of my pyramidal insulated top for the Zero, but I’m waiting to get my SV08 upgraded so I can print the top for the Zero in one piece.

1 Like
3

Just hope it saves someone a hour or two of searching around online, & having that moment of trepidation when the printer is powered on, wondering whether it’s going to work else go pop. :smiley: It seems quite a nice sensor. I’ve tested it on both runout & movement, & it appears to pick both conditions up fine.

There’s also a good length of cable on the supplied loom, as this photo shows, where I’ve had to bundle it, (the green cable ties), so the sensor has enough cable to be placed elsewhere.

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4

I installed one on my Zero just this past weekend. Used the same connectors.
A note on the motion sensor, you may need to disable it in Mainsail when printing TPU/TPE. I printed a part in TPU the next day, and after three pauses from tripping the motion sensor, turned it off for the rest of the print. Works fine with “hard” filaments.

2 Likes
5

What have you set as the detection length in your config?

6

I use a default of 4.88, so slightly more than double the trigger distance.
Issue is that TPU stretches when there’s any drag at all, and apparently in my case, it stretched more than the trigger value.

I could set the trigger length larger, but that has negative affects on recovery. I’ve yet to see any way to programatically/dynamically change the trigger value using the filament gcode, so for now, I just disable the motion sensor when printing TPU.

1 Like