<p>I would comment but I don’t have enough reputation yet -</p>
<p>Are you using the Creality firmware, Marlin, RepRap, or the Stock BIGTREE firmware? Also, have you modified it at all?</p>
<p>If you’re still using the firmware that came on the printer or Marlin firmware this thread could offer some insight. Read down through all of the comments because several people had really good tips, and the OP actually posted an update with how he solved it:</p>
<blockquote>
<p>It seems that the settings stored in the printer overwrides the  FILAMENT_RUNOUT_DISTANCE_MM  in the firmware. So I just went the the printer configuration -&gt; advance configuration -&gt; filament and then I changed the runout distance and stored the settings. <a href="https://www.reddit.com/r/MarlinFirmware/comments/jv8lso/btt_filament_runout_sensor_always_triggers_runout/?utm_source=share&amp;utm_medium=ios_app&amp;utm_name=iossmf" rel="nofollow noreferrer">Source</a></p>
</blockquote>

CC BY-SA 4.0
2021-11-11T14:03:48.690Z
I have marlin.  I mentioned that "that even if you set it to 7 mm in the firmware, it doesn't always take effect and you have to go to the configuration menu in your printer and set it, then store the settings. I've done that as well"
Joseph Crozier
CC BY-SA 4.0
2021-11-11T11:29:52.217Z
2021-11-11T14:03:37.200Z
2021-11-11T14:03:37.200Z
BackTrack
<p>(This is a pretty much duplicate post from one I put <a href="https://www.reddit.com/r/BIGTREETECH/comments/qpdhe3/getting_btt_filament_sensor_to_work/?utm_source=share&amp;utm_medium=web2x&amp;context=3" rel="nofollow noreferrer">over on the Reddit</a>, but it hasn't received a lot of traction over there so I figured I'd post):</p>
<p>Like many posts I've seen on the internet, I'm having trouble getting my BTT smart filament sensor to work.</p>
<p><strong>Relevant Specs about my printer</strong>:</p>
<ul>
<li>Ender 3 Pro</li>
<li>BTT E3 RRF Mainboard with IDEX module</li>
<li>Marlin Firmware I've edited in ways I mention below</li>
</ul>
<p><strong>What is going wrong</strong>:</p>
<p>It triggers way too easily.  Right as a print starts, it'll trigger and say I ran out of filament.  And/or it'll make it maybe half a layer and then trigger.</p>
<p><strong>Steps I've taken</strong>:</p>
<ul>
<li>I started by following the Teaching Tech YouTube video to get started and install it. Tried to match literally every change of his in the firmware I saw.  Things like runout distance set to 7 and runout state set to low instead of high.
<ul>
<li>Quick note on those.  In several places (<a href="https://www.reddit.com/r/BIGTREETECH/comments/le8b2t/btt_smart_filament_sensor_connected_to_skr_13_not/" rel="nofollow noreferrer">like this</a>) comments suggest changing the distance to more than 7 mm to make it less 'picky'.  But in several comments (like <a href="https://www.reddit.com/r/MarlinFirmware/comments/jv8lso/btt_filament_runout_sensor_always_triggers_runout/" rel="nofollow noreferrer">here</a>, and <a href="https://www.makenprint.uk/3d-printing/3d-printing-reviews/3d-printer-accessory-reviews/btt-smart-filament-sensor-guide/" rel="nofollow noreferrer">here</a>), people suggest the official recommendation from BTT is 7 mm and there's a reason to set it at that.   I've tried all sorts of distances and none seem to work.</li>
<li>In at least one place (like <a href="https://www.reddit.com/r/MarlinFirmware/comments/jv8lso/comment/gci6dkq/?utm_source=share&amp;utm_medium=web2x&amp;context=3" rel="nofollow noreferrer">here</a>) people suggest that even if you set it to 7 mm in the firmware, it doesn't always take effect and you have to go to the configuration menu in your printer and set it, then store the settings.  I've done that as well.</li>
<li>I've set the runout state to either low or high, seems to still falsely trigger either way.</li>
</ul>
</li>
<li>The <s>only solution I haven't tried yet (will try tonight when I get home)</s>  (did that , still no luck) is in <a href="https://www.reddit.com/r/ender5/comments/j7ph2s/comment/gmjoygp/?utm_source=share&amp;utm_medium=web2x&amp;context=3" rel="nofollow noreferrer">this comment</a> it suggests adding <code>M75</code> to my code to 'start the print job timer' so it won't trip 'after the initial 7 mm runout'.  Could someone explain that one to me?  Also, I feel like that's not it because even when I let it go through its paces and unload and then load, it'll trip again soon after.</li>
</ul>
<p><strong>The problem:</strong></p>
<p>I just feel like it's still <strong>way</strong> too sensitive.  And sure, in an ideal world I want it to detect all the things it's 'supposed' to detect like jams, tangles, etc...   but I really just care the most about it noticing I ran out of filament.
Are there any settings in the firmware or anywhere else I should take a look at?</p>
<p>My latest thought is that maybe I have the sensor mounted in a different direction than it should be?  Every video or picture I see online looks like the filament is going the opposite direction compared to what I have, but I've also seen comments where it says that doesn't matter.</p>
<p>I also have <a href="https://www.raverobot.com/how-to-add-a-smart-filament-runout-sensor-to-the-ender-3/" rel="nofollow noreferrer">seen comments like here where the author</a> recommends a HUGE runout distance (50) as that could be a problem. I'm willing to try that.</p>

<creality-ender-3><bigtreetech><filament-sensor>
Getting BTT filament sensor to work
Joseph Crozier
# Getting BTT filament sensor to work

(Asked by: username_0 on 2021-11-08)

(This is a pretty much duplicate post from one I put [over on the Reddit](https://www.reddit.com/r/BIGTREETECH/comments/qpdhe3/getting_btt_filament_sensor_to_work/?utm_source=share&utm_medium=web2x&context=3), but it hasn't received a lot of traction over there so I figured I'd post):

Like many posts I've seen on the internet, I'm having trouble getting my BTT smart filament sensor to work.

**Relevant Specs about my printer**:

* Ender 3 Pro
* BTT E3 RRF Mainboard with IDEX module
* Marlin Firmware I've edited in ways I mention below

**What is going wrong**:

It triggers way too easily. Right as a print starts, it'll trigger and say I ran out of filament. And/or it'll make it maybe half a layer and then trigger.

**Steps I've taken**:

* I started by following the Teaching Tech YouTube video to get started and install it. Tried to match literally every change of his in the firmware I saw. Things like runout distance set to 7 and runout state set to low instead of high.
  + Quick note on those. In several places ([like this](https://www.reddit.com/r/BIGTREETECH/comments/le8b2t/btt_smart_filament_sensor_connected_to_skr_13_not/)) comments suggest changing the distance to more than 7 mm to make it less 'picky'. But in several comments (like [here](https://www.reddit.com/r/MarlinFirmware/comments/jv8lso/btt_filament_runout_sensor_always_triggers_runout/), and [here](https://www.makenprint.uk/3d-printing/3d-printing-reviews/3d-printer-accessory-reviews/btt-smart-filament-sensor-guide/)), people suggest the official recommendation from BTT is 7 mm and there's a reason to set it at that. I've tried all sorts of distances and none seem to work.
  + In at least one place (like [here](https://www.reddit.com/r/MarlinFirmware/comments/jv8lso/comment/gci6dkq/?utm_source=share&utm_medium=web2x&context=3)) people suggest that even if you set it to 7 mm in the firmware, it doesn't always take effect and you have to go to the configuration menu in your printer and set it, then store the settings. I've done that as well.
  + I've set the runout state to either low or high, seems to still falsely trigger either way.
* The ~~only solution I haven't tried yet (will try tonight when I get home)~~ (did that , still no luck) is in [this comment](https://www.reddit.com/r/ender5/comments/j7ph2s/comment/gmjoygp/?utm_source=share&utm_medium=web2x&context=3) it suggests adding `M75` to my code to 'start the print job timer' so it won't trip 'after the initial 7 mm runout'. Could someone explain that one to me? Also, I feel like that's not it because even when I let it go through its paces and unload and then load, it'll trip again soon after.

**The problem:**

I just feel like it's still **way** too sensitive. And sure, in an ideal world I want it to detect all the things it's 'supposed' to detect like jams, tangles, etc... but I really just care the most about it noticing I ran out of filament.
Are there any settings in the firmware or anywhere else I should take a look at?

My latest thought is that maybe I have the sensor mounted in a different direction than it should be? Every video or picture I see online looks like the filament is going the opposite direction compared to what I have, but I've also seen comments where it says that doesn't matter.

I also have [seen comments like here where the author](https://www.raverobot.com/how-to-add-a-smart-filament-runout-sensor-to-the-ender-3/) recommends a HUGE runout distance (50) as that could be a problem. I'm willing to try that.

**Tags:** creality-ender-3, bigtreetech, filament-sensor

---

## 1 answers

### Answer by username_1 on 2021-11-11. Score: -1

I would comment but I don’t have enough reputation yet -

Are you using the Creality firmware, Marlin, RepRap, or the Stock BIGTREE firmware? Also, have you modified it at all?

If you’re still using the firmware that came on the printer or Marlin firmware this thread could offer some insight. Read down through all of the comments because several people had really good tips, and the OP actually posted an update with how he solved it:

> It seems that the settings stored in the printer overwrides the FILAMENT\_RUNOUT\_DISTANCE\_MM in the firmware. So I just went the the printer configuration -> advance configuration -> filament and then I changed the runout distance and stored the settings. [Source](https://www.reddit.com/r/MarlinFirmware/comments/jv8lso/btt_filament_runout_sensor_always_triggers_runout/?utm_source=share&utm_medium=ios_app&utm_name=iossmf)

> **Comments:**
> **username_0**: I have marlin.  I mentioned that "that even if you set it to 7 mm in the firmware, it doesn't always take effect and you have to go to the configuration menu in your printer and set it, then store the settings. I've done that as well"  

---

