Electrode Maintenance; Technical Data; Specifications - OHAUS ST400 Manual De Instrucciones

ST400 & ST400M Portable Meter
4.3

Electrode maintenance

For pH electrode:
Make sure that the electrode is always stored in the storage solution in a protective bottle. Do not
dry it out. Avoid storage in distilled water. The storage solution is 3M KCl solution. Please pay
attention to whether the reference solution is leaked or crystallized. The reference solution is
saturated KCl or AgCl saturated KCl solution..
The smiley face, poker face or crying face symbol on the meter represents the quality of the last
calibration, not necessarily the current state of the electrode; to determine whether the current
state of the electrode is good or bad, please recalibrate.
If the electrode response becomes sluggish or the slope is not acceptable, try the following:
o
If the electrode dry out, soak the electrode in 0.1M HCl for 24 hours.
o
For fat or oil contaminant, degrease the membrane with cotton wool soaked in either
acetone or a soap solution.
After electrode treatment, a new calibration should be performed. If the electrode slope is still not
acceptable, the electrode might need to be replaced.
For conductivity electrode:
Please note that always store a four-ring electrode in a dry environment. Make sure that the
measuring fluid must reach or above the mark on the outer plastic sleeve. See the corresponding
conductivity electrode manual.
5

TECHNICAL DATA

5.1

Specifications

Equipment Ratings:
- Pollution degree 2;
- Installation category II;
- Altitude 2000 m;
- Humidity: Maximum 80% for temperatures up to 30° C decreasing linearly to 50% at 40° C;
- Electrical supply: 5VDC 1A (For use with CSA Certified (or equivalent approved) power
source, which must have a limited-energy output);
- Indoor use;
- Ambient temperature range: 5° C to 40° C;
- The main supply voltage fluctuations are not to exceed ±10% of the nominal supply voltage;
- Waterproof and dustproof grade: IP67.
ST400 pH
Measurement technical specification：
Measurement technical
specification
ST400 pH：
Digital measuring range
Resolution
Measurement range of digital unit: (-2.00 -16) pH
Measurement range: (0~14) pH, (-1999 ~ 1999) mV
Instrument level: 0.01
-2.00～16.00 pH
-1999～1999 mV
-5 ° C～110 ° C
0.01 pH
1 mV
EN-19