SPECIFICATIONS miniLab H128
Catalog Number
H128
Model miniLab
H128
Meter
Pocket-sized waterproof pH meter
Sensor
Silicon chip pH sensor
Calibration
1,2, or 3 Point
Buffer Recognition
Automatic pH 4.01, pH 7.00, pH 10.01
Temp. Compensation
Automatic
Reference
Replaceable KCl gel filled. Part No. RF01-01
pH Range:
pH 2.00 to pH 12.00
Resolution:
0.01 pH
Accuracy
±0.02 pH
Operating Temp. Range
5 to 40 °C (40 °F to 105 °F)
Display
LCD digital display (0.01 pH resolution)
Power
Auto Shut Off. Two 3v lithium batteries CR2032
Battery Life
150 hours continuous. 10 hour low battery warning.
Dimensions
152.4 x 28.57 x 16.38mm (6.0” x 1.125” x .645”) 53.94 g (1.03 oz)
Shipping Weight
1.0 lb. (.45 kg)
Troubleshooting Guide
If an error message is displayed first check the following:
No pH buffer on the pH sensor.
If the meter is reading 0.00 or 14.00, the semsor is dry
Air bubbles are trapped on the sensor surface.
pH sensor is dirty. See “Cleaning the Sensor”.
pH sensor and reference is not in solution.
BAT Message Displayed
Batteries are too low for reliable measurement. See “Replace Batteries”
(Battery Icon) Displayed
Approximately 10 hours of battery life remains. Replace batteries immediately.
Difficulty in Calibrating or in Obtaining a Stable Reading:
pH sensor is dirty. See “Cleaning the Sensor”.
The reference electrode has reached the end of its useful life. Replace reference electrode.
Interference from direct sunlight. Shade sensor from sunlight.
pH or temperature of sample is changing.
Sample has low ionic strength (tap water, distilled water).
Notes on calibration and measurement:
• Measurements cannot be made while CAL is displayed. Be sure to complete the calibration procedure before
taking pH measurements.
• Always begin a measuring session with a calibration.
• Be sure to use pH 7.00, 4.01 or 10.01 buffer as a calibration standard.
• The use of other solutions to calibrate may make measurements inaccurate.
• Rinse the sensor with distilled or deionized water when testing the pH of tap water, rainwater, or clean water.
• Although the pH meter has automatic temperature compensation, always keep the pH buffers and the samples at
the same temperature.
• To measure solids such as soil, make a slurry of the sample in deionized or distilled water.
• Keep the sensor surface clean. See “Cleaning the Sensor”.
• A white powder or gel at the probe tip is KCl reference solution. Clean from sensor before use.
• To change C°or F° temperature unit, turn off meter. Press and hold CAL 1 button, then press the POWER button
to turn meter back on.
DO:
Soak the probe in pH 7.00 (neutral) pH buffer for 5 minutes if the probe is new or has not been in regular use.
Clean the probe regularly with soft cotton tipped swab.
STORE THE PROBE DRY with the protective cap covering the probe tip. No electrode storage solution is required.
For maximum accuracy always begin each measuring session with a calibration.
Calibrate at the same temperature as the sample solution. Although the meter has automatic temperature compensation,
best results will be achieved if the calibration buffers and sample are the same temperature.
Be sure the surface of the sensor in the probe is free from any deposits or films. See the cleaning instructions in this manual.
Always place the protective cap over the sensor tip when finished measuring.
DO NOT
DO NOT store the sensor in solution or use for long term pH measuring applications.
DO NOT use below 5 °C or above 40 °C (40 - 105 °F).
DO NOT leave the sensor uncapped for long periods of time.
DO NOT allow oil, fat, food particles, starch, protein, or other materials to remain on the pH sensor after use.
DO NOT use a sharp metal object (needle, pin, etc.) to clean the pH sensor surface.
DO NOT take readings in direct sunlight. Direct sunlight may cause unstable readings or difficulty in calibration.
DO NOT use in an environment that will damage pH sensor or meter: Organic solvents (acetone, toluene, thinner, oils), strong
acids (pH 0 - 2), strong alkalis (pH 12 - 14), abrasive samples, silicon etching compounds (hydrofluoric acid).
DO NOT press the POWER or CAL buttons with sharp objects.
DO NOT submerge the meter. The meter has water-resistant O-ring seals, it is not submersible.
DO NOT use in environments with static electricity. Electrostatic discharge may permanently damage the probe.
Error Codes:
CODE Description
Solution
E06
pH sensor slope error
Clean probe. If error persists, replace meter.
E07
pH sensor voltage error
Clean probe. Be sure sample liquid covers both sensor and reference junction.
CODE Description
Solution
E08
Too long to calibrate Clean probe. If error persists, replace reference. If error still persists,
replace meter.
E13
Temperature Sensor error Replace meter
Cleaning the Sensor:
1. Clean the sensor with soapy water and a toothbrush or
cotton tipped swab.
2. Rinse the sensor with water.
3. Recalibrate.
CAUTIONS:
Do not scratch the pH sensor.
Do not press the reference electrode junction.
White powder or gel on the pH sensor is KCl reference solution. Clean before using.
Do not clean the sensor with organic solvents such as acetone, methanol, or thinner.
Replacing the Batteries:
1. Wipe the pH meter dry.
2. Pull the meter case apart as shown to the right.
3. Gently pry out the batteries and replace with two 3v lithium CR2032 batteries.
The (+) side of the batteries should face up.
4. Be sure the O-ring is not damaged and is in the correct position.
5. Reassemble the meter.
6. Recalibrate.
CAUTIONS:
Do not open the meter case if the pH meter is wet.
Always replace both batteries at the same time.
Dispose of batteries properly.
O-Ring
NOTE:
The service life of the reference electrode will vary
according to the frequency of measurement, temperature,
and other measurement conditions.
CAUTIONS:
Do not remove the reference electrode if the meter is wet.
Be sure that the O-ring seals properly. If the O-ring does
not seal properly to the meter, liquid may enter and cause
permanent damage.
Replace the Reference When...
• Liquid in the reference electrode is
depleted. Shown to the right.
• Response time slows
• There is difficulty in obtaining a stable
reading.
Replacing the Reference.
1. Wipe the pH meter dry.
2. Pull the reference electrode out of the
pH meter as shown to the right.
3. Check to be sure that the watertight
O-ring is clean and properly seated on
the new reference.
4. Insert the new reference into the pH
meter. Part No. RF01-01.
5. Recalibrate the pH meter.
!
!
!
!
Bubble
Large air bubble,
time to replace reference electrode.
O-Ring
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