AMS humidity sensor wrong or not?


I bought cheap humidity sensors and it reports 10% of humidity in my AMS, but Bambustudio just show a green circle, no bars :

So now I wonder how much humidity no bar, one bar, two bars etc…means ? less than 10% ?

Also the MQTT message reports humidity: 5 (always 5, I only got one time 4), dont know the multiplier factor that should be applied to get the ASM humidity sensor value, does someone have this information ?

NB: I have a better humidity sensor and I have checked that those cheap sensors I bought doesn’t give too wrong results.

BL had an article about the AMS humidity sensors awhile ago. They changed it from reporting a % value to the current graphic. IIRC, they said the AMS reads several sensors and from those readings create the bar graph you see. As for the cheep hygrometers you can get on Amazon, they don’t read below 10%. So getting a 5 on MQTT means the AMS is doing good for humidity. Anything less than 3 indicates it is time to change the desiccant.


Thanks for all those informations, I am just wondering because I would like to use PVA as support (and know if I can let the spool inside the AMS), any links to this article ?

EDIT: the problem is that they let a popup that talk about green bars in Bambu studio when hovering mouse over the humidity icon

Not sure where it was. I think it was a response to someone asking about the change to the display. Try doing a search in the forums here.

As for using PVA, I wouldn’t leave it in the AMS for any length of time when not using. I’m not all that sure how good the AMS is in stopping humidity from getting in. Also, you might be opening and closing it a lot swapping other filaments.

It is an old unopened spool, I am afraid that I have no location that would be drier than 10%/20%.

I have designed and added additional desiccants boxes in my AMS, so it is probable but not certain that it works as well as a “dry box”.

Keep in mind that inexpensive hygrometers, of the kind we’re all sticking in the AMS, don’t read below 10%.

Yep right (I use them more as an indicator than a real measure), but I assume if it give 10%, it should not be more than 20%, that’s why I said 10/20% :wink:

I would prefer a number value for humidity, not the tiny graphic they introduced. Why not make this a configurable item for the printer?

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If you refer to the typical cheam round hygrometers from amazon, they typically vary a few %.

So if it reads 10% i would expect the actual humidity to be lower than ~12%, so anywhere between 0 ans 12%

Now I can see my AMS humidity level live :slight_smile:


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Thanks for the link !!!