Hach H128 Operating Instructions

mini_man_H128 9/8/09 9:29 AM Page 1
OPERATING INSTRUCTIONS
Model H128
pH Meter with Silicon Chip Sensor
IQ Scientific Instruments
1. Probe Tip
6. Protective Cap 7. Clip
1
Remove cap from probe Rinse the probe in tap
tip and turn on the meter. water and blot dry.
Continue as follows for two-point calibration
TIP: When using two-point calibration, always bracket the expected pH value of the sample.
For example, if the expected pH of a sample is pH 5.00, use pH 7.00 and pH 4.01 buffer.
8. Apply one drop of either pH 4.01 or pH 10.01 buffer to the probe tip.
9. Depress the CAL 2 button with the tip of the clip. The meter will automatically identify the
buffer value.
10. The CAL icon will flash until a stable reading is obtained. When the CAL disappears,
calibration of the second point is complete.
11. Rinse the probe in tap water and blot dry. To measure the pH of a sample, go to Step 12.
To continue with a three point calibration, go to Step 13.
12. Now measure the sample pH by placing a single drop on the probe tip or dipping the probe tip
into solution.
When finished, always rinse the probe and replace the protective cap.
DOC022.53.80061
5. LCD Display
10. CAL 1 Button
11. CAL 2 Button
9. POWER Button
8. Bubble
4. Reference Junction
2. pH Sensor
3. Reference Electrode
Calibration and Measurement Instructions
2 3
Apply one drop of 7.00
buffer to the probe tip. Be
sure to cover both the
reference junction and the
pH sensor.
Parts
1. Probe Tip
2. pH Sensor
3. Reference Electrode
4. Reference Junction
5. LCD Display
6. Protective Cap
7. Clip
8. Bubble
9. POWER Button
10. CAL 1 Button
11. CAL 2 Button
4
5
Depress the CAL 1 button The CAL and 7.00 will
with the tip of the clip. flash until a stable reading
is obtained. When the
CAL disappears and 7.00
stops blinking, calibration
is complete.
Continue as follows for three point calibration
TIP: Use three-point calibration when the expected sample pH values are completely unknown or
range both above and below pH 7.00.
13. Apply one drop of the remaining buffer (either pH 4.01 or pH 10.01) to the probe tip.
14. Depress the CAL 2 button with the tip of the clip. The meter will automatically identify the
buffer value.
15. The CAL icon will flash until a stable reading is obtained. When the CAL disappears, calibration
of the third point is complete.
16. Rinse the probe in tap water and blot dry.
17. Now measure the sample pH by placing a single drop on the probe tip or dipping the probe tip
into solution.
5600 Lindbergh Dr., Loveland, CO 80539
T T e e c c h h n n i i c c a a l l S S u u p p p p o o r r t t : :
(800) 227-4224 (U.S.A. only)
Fax (970) 669-2932
orders@hach.com • www.hach.com
International customers:
Tel +001 (970) 669-3050
Fax +001 (970) 669-2932
intl@hach.com
pH sensor and reference electrode.
Fast response silicon chip pH sensor with built-in temperature sensor.
Replaceable saturated KCl Ag/AgCl electrode.
Measurement is made when the reference junction and the pH sensor are
immersed in the solution.
CAL (blinking): Calibration in process. Measurement cannot be made.
CAL (off): Measurement can be made.
BAT: Low battery indicator. Replace batteries.
Always replace the cap after use.
Use the tip of the clip to depress the CAL button.
The reference solution bubble indicates the life of the reference electrode.
Press to turn the meter on or off.
Button for pH 7.00 calibration.
Button for pH 4.01 or pH 10.01 calibration.
6
Reference Junction
pH Sensor
Rinse the probe in tap Now measure the sample
water and blot dry. pH by placing a single
To measure the pH of a drop on the probe tip or
sample, go to Step 7. dipping the probe tip
To continue with a two into solution.
point calibration, go to
Step 8.
7