JOWA M-93
Oil content meter (OWS monitor)
JOWA service note (2003) on calibrating the M-93 oil content meter: preparing the measuring cell, hardware calibration with potentiometers on the NSC (turbidity), SC1 and SC2 (light scatter at two angles) signals, and software calibration on fresh water and the reference solution.
Maintenance procedures
Calibration of the JOWA M-93 monitor
- Clean the quartz tube of the cell thoroughly with a degreaser and brush; if it is cloudy, use citric acid. p. 1Dirty quartz glass gives an error from the very start
- Fill the cell with fresh water and wait 30 s. Holding "Test NSC", adjust potentiometer P15 and DIP switch 1 until the left display shows 55. p. 1
- Drain the cell, fill with reference solution (stir without bubbles), wait 30 s. Holding "Test SC1", adjust P14 and DIP 2 to ≈275 on the right display. p. 1
- Holding "Test SC2", adjust P5 and DIP 3 to ≈375. p. 1
- Software calibration: drain the cell, fill with fresh water, after 30 s press "Cal". p. 1
- Check "Test NSC" (≈55), right display 20–90 and "Test SC2" 5–50 (higher means dirty or scratched glass), then press "H2O" — after 5 s the left display shows 0-0. p. 1
- When "Cal Ref" lights up, drain the water, fill with reference solution, after 30 s check SC1 (≈275) and SC2 (≈375). p. 1
- Press "Ref" before the count ends — the left display shows 0-0. If an alarm code appears, see the alarm list in the manual. p. 1
Faults and what to do
Technical specifications
| NSC on fresh water (hardware calibration) | ≈ 55 | p. 1 |
|---|---|---|
| SC1 on reference solution | ≈ 275 | p. 1 |
| SC2 on reference solution | ≈ 375 | p. 1 |
| Reference solution | 1 ml of calibration liquid per 100 ml of fresh water | p. 1 |
| Clean cell check (right display) | SC1 20–90, SC2 5–50 | p. 1 |
Source: manufacturer's manual “OWS JOWA M-93 monitor - Calibration”, 1 pages. Page numbers refer to the original. Check against the manual on board before work.
This page was translated automatically from the manual summary. Part numbers, codes and page numbers are as in the original.