Weight looks wrong

Two different things can go wrong: the scale itself shows a wrong or restless number, or the number is fine but cannot be saved to Spoolman.

The scale reading is wrong or does not settle

What you see	What it means	What to do
`The weight did not settle. Keep the spool still and weigh again.`	The reading did not stay within 2 g for 1.5 seconds. The station gives up after 20 seconds.	Let the spool rest. Make sure no filament is pulled tight to the printer and nothing touches the platform.
`Scale is still moving. Leave the spool still and retry.`	The same.	The same.
`Measurement failed or timed out. No inventory update`	The same, or the scale stopped answering. Nothing was saved.	Weigh again.
`Scale zero has shifted. Empty the platform, then use Tare in Settings > Calibrate scale and retry.`	The scale reads more than 30 g below zero.	Empty the platform. Touchscreen: Settings → Calibrate scale → TARE EMPTY PLATFORM. Browser: Weigh → Scale setup → Tare.
`Scale overload detected. Remove weight and retry.`	The load is above the cell's capacity plus the overload margin (by default 5500 g for the 5 kg cell, 2200 g for the 2 kg cell). It also appears when the load-cell signal is out of range, for example with a loose or swapped cell wire.	Remove the load. If the platform is empty, check the load-cell wires, check that the right cell size is selected and calibrate again.
The Home button reads CALIBRATE, or `Calibration required`	The scale has no calibration. This also happens after you change the load-cell size or do a factory reset.	Tare and calibrate
`Scale hardware unavailable`	The scale converter does not answer.	Check the scale wiring.
`The scale is busy. Try again in a moment.` (also "Try TARE again" or "Try calibrating again")	Another measurement is running.	Wait and try again.
`Saving the previous weight to Spoolman. Try again in a moment.`	The last weight is still being saved to Spoolman. The browser's Weigh button reads "Saving to Spoolman…" meanwhile.	Wait a few seconds and weigh again.
`The scale stopped responding. Reconnecting to it; weighing is unavailable until it answers again.`	The scale converter stopped answering, for example after a short power drop on the scale.	Wait. The station reconnects to the scale by itself and keeps the calibration; you do not need to restart it. If the message stays, check the scale wiring and power.
`The platform is not empty (reads X g). Remove everything, then tare. If it is empty, tare again within 15 seconds.`	You asked for a tare while the calibrated scale reads more than 50 g.	Remove the spool and everything else from the platform, then tare. If the platform is already empty, the zero itself has moved: tare again within 15 seconds and the station accepts it.
The weight is steady but wrong by the same factor every time	The calibration is off, or the wrong cell size is selected.	Check Settings → Scale → Edit Load-cell profile in the browser (5 kg or 2 kg), then calibrate again with a known weight.
The weight changes when you touch the case or move a cable	The platform is not free.	Scale platform and enclosure
A known weight reads a few grams lower (or higher) some time after calibrating, and drifts slowly while it sits on the platform	Warm-up drift or load-cell creep. Right after power-on the board warms up for 10–15 minutes and the reading moves with it. A load cell under a steady load also creeps slowly, more so when it is close to a warm part or when the platform rubs on something.	Leave the station switched on for 15 minutes, then tare and calibrate again. Keep the load cell away from the touchscreen board and other warm parts, mount it only by its two screw pairs, and make sure the platform and cables touch nothing. If a known weight still moves by more than a few grams over ten minutes, the load cell itself may be poor; try another one.

Look at the raw numbers

Browser: Settings → Scale → Scale diagnostics shows Raw, Filtered, Zero and Factor. Touchscreen: Settings → About / Advanced, section SCALE AND SCREEN, line Raw reading.

Press on the platform: Raw must change. If it never changes, a load-cell wire is loose or on the wrong terminal.
With the platform empty and untouched, Raw should stay nearly constant. If it wanders, look for a cable pulling on the platform or a loose screw.

Calibration messages

What you see	What to do
`No reference weight detected. Place the reference weight on the platform and retry.`	Put the known weight on the platform after taring, wait until it is stable, then calibrate.
`calibration reference produced too few ADC counts`	The scale hardly noticed the weight. Use a heavier known weight; check that the platform rests on the load cell only.
`Enter a valid reference weight`	Enter the weight in grams: more than 0 and not more than the cell's capacity.

On the touchscreen, tare and calibration results ("Tare complete", "Calibration complete", or "Tare failed: …" / "Calibration failed: …" with the reason) stay on the screen until your next tap or until you leave the page.

The filament weight does not make sense

The station shows three numbers after weighing. Touchscreen: Empty spool, Filament now, In Spoolman. Browser: Empty spool / tare, Measured filament, Spoolman currently.

Filament now = scale reading − empty spool weight. So a wrong filament weight with a correct scale reading means the empty spool weight is wrong. Check it on the spool in Spoolman. How the station picks it: Weigh a spool and save the weight.

The weight cannot be saved

Nothing can be saved yet

What you see	What it means	What to do
`This spool is not linked to Spoolman yet. Link the tag to a spool (Manage tag), then weigh again.`	The station does not know which spool this is. Also shown when no tag is on the reader or Spoolman is offline.	Place the tagged spool; link the tag in Manage tag; check Spoolman.
`The spool on the station changed. Weigh again.`	The tag was lifted or swapped, or settings changed, after the measurement.	Weigh again and keep the spool in place until it is saved.
`Spoolman already matches this weight. Nothing to update.`	The difference is within the tolerance (5 g by default). This is not an error.	Nothing.
`Saving weights is turned off: …`	Your Spoolman version is not a tested one, or Spoolman is offline.	Spoolman problems
`The weight tolerance setting is invalid. Check Settings.`	The tolerance under Settings → Scale → Weight updates is not usable.	Enter a valid number of grams there.

Spoolman is missing data

What you see	What it means	What to do
`The empty spool weight is unknown. Set it on the spool in Spoolman, then weigh again.`	Neither the spool, the tag, the filament nor the vendor has an empty spool weight.	Set it on the spool in Spoolman.
`This spool has no initial weight in Spoolman. Set its initial weight in Spoolman, then weigh again.`	The spool has no initial weight.	Set the initial weight in Spoolman.
`Spoolman has no remaining weight for this spool. Set its initial weight in Spoolman, then weigh again.`	The same.	The same.
`Spoolman refused the new weight (HTTP 400). Check that the spool has an initial weight in Spoolman.`	The same.	The same.

The numbers disagree

What you see	What it means	What to do
`The scale reads less than the empty spool weight. Check that the spool is on the scale and its empty weight is right.`	The reading is lower than the empty spool alone should be.	Put the spool on properly; correct the empty spool weight; tare the empty platform.
`The measured filament (N g) is more than this spool's initial weight in Spoolman (M g). Check the empty spool weight, or correct the initial weight in Spoolman.`	The spool holds more filament than Spoolman says it started with. Up to 10 g over is accepted as a full spool.	Correct the empty spool weight or the initial weight in Spoolman.
`Spoolman usage changed while this weight was being processed. No inventory value was overwritten. Weigh again`	Spoolman's numbers changed while you were weighing, for example because a print used filament.	Weigh again.

Each measurement can be saved once. To save again, weigh again.