SOP — Anton Paar DMA 35 Maintenance¶
FUERST WIACEK Version 1.2 | Lab — Anton Paar DMA 35 portable density meter | Frequency: clean after each session, calibration check monthly
Purpose¶
This SOP covers the full cleaning procedure, calibration, and maintenance schedule for the Anton Paar DMA 35 portable density meter used for daily Plato readings during fermentation monitoring. Proper maintenance ensures measurement accuracy and extends the life of the instrument.
For daily quick-rinse after use, refer to the note in the Fermentation Monitoring SOP.
Equipment¶
- Anton Paar DMA 35
- Small pitcher
- Washing-up liquid (Spüli)
- Fresh water
- Distilled water (for calibration)
- Alcohol (isopropanol)
Cleaning Procedure — After Each Use¶
Perform this full cleaning at the end of each session or at the end of the day.
- Prepare a small pitcher of warm water with a single drop of Spüli.
- Flush the instrument 2–3 times with the soapy water. Expel after each draw.
- Flush 2–3 times with fresh water. Expel after each draw.
- Flush once with alcohol. Expel.
- Draw air through using the instrument's integrated pump until the measuring cell is visibly dry.
Note
The alcohol flush displaces residual water and speeds drying. Do not skip it.
Warning
Never leave liquid sitting in the instrument when storing. Always complete the air-drying step.
Calibration¶
The DMA 35 is calibrated using distilled water as a reference. Calibrate whenever readings appear inconsistent, after the instrument has been knocked or dropped, or after any service.
Calibration Procedure¶
- Ensure the instrument is clean and dry — run the full cleaning procedure first.
- Open the menu on the DMA 35 and navigate to the calibration function.
- Draw a fresh sample of distilled water into the instrument. Follow the on-screen prompt and confirm when stable.
- Log the calibration date and result in the maintenance log below.
Note
Use fresh distilled water only. Do not use water that has been sitting open.
Maintenance Schedule¶
| Task | Frequency | Notes |
|---|---|---|
| Full cleaning (soapy water → fresh water → alcohol → air dry) | After each session | See cleaning procedure above |
| Calibration check | Monthly | Log result in maintenance log |
| Visual inspection (seals, cap, casing) | Monthly | Check for cracks, wear, or damage |
| Battery check | As needed | Replace when low battery indicator appears |
| Full service / factory check | As recommended by Anton Paar | Contact Anton Paar or authorised service partner |
Maintenance Log¶
Calibration entries, services, and incidents are recorded in the Anton Paar maintenance log — see Spreadsheets reference for the location.
For each calibration, log:
- Date
- Result (pass / fail / value)
- Notes — anything unusual (knock, drift, replaced parts)
- Initials
Troubleshooting¶
| Issue | Likely Cause | Action |
|---|---|---|
| Reading inconsistent or drifting | Residue in measuring cell | Perform full cleaning procedure. Recalibrate. |
| Reading consistently high or low vs. reference | Calibration drift | Recalibrate with distilled water. |
| Instrument slow to stabilise | Sample contains bubbles or residue | Flush more thoroughly before reading. Ensure no gas pockets. |
| IPA not available | Missing consumable | Substitute with a longer air-dry sequence. Restock alcohol. |
| Display shows error after knock or drop | Potential sensor damage | Do not use. Contact Anton Paar for inspection. |