601XXX-EN V1.4 9/13
pH Electrodes Instruction Sheet Models 601100, 601500 and 60120B
Electrode Specifications Model number 601100 60120B 601500 Description Flat surface combination pH
electrode with gelled reference solution
Mini combination pH electrode with sealed gelled reference filling solution and detachable bulb guard
General-purpose combination pH electrode with sealed gelled reference filling solution and detachable bulb guard
Dimensions 15 x 115 mm 10 x 126 mm 12.5 x 155 mm Construction material Polymer housing, flat glass bulb Polymer housing, glass bulb Polymer housing, glass bulb Measuring range 0 to 14.0 pH units 0 to 14.0 pH units 0 to 14.0 pH units Temp. range 0-80oC 0-80oC 0-80oC Reference junction Teflon Ceramic Ceramic Reference type Ag/AgCl (silver silver chloride) Ag/AgCl (silver silver chloride) Ag/AgCl (silver silver chloride) Isopotential point ~7.0 pH ~7.0 pH ~7.0 pH Precision 0.02 pH units 0.02 pH units 0.02 pH units Connector BNC BNC BNC Cable length 1 meter (39) 1 meter (39) 1 meter (39) Storage container Bottle Cap Bottle
General Electrode Procedure 1. To avoid damage to the electrode when removing it from or
inserting it into the soaking bottle; a) Unscrew the bottle cap. b) Remove the electrode and cap from the bottle. c) Slide the cap off the electrode. d) Reverse this procedure when storing the electrode.
2. Rinse the electrode with deionized or distilled water. 3. Carefully shake electrode to ensure that any air bubbles in the
bulb or lower stem of the electrode are dislodged upwards. 4. Blot electrode with tissue. 5. Connect electrode to pH meter and follow the pH meter
manufacturers instruction for calibration.
Before Measurement
1. Generally, the sample should be aqueous and fall within the range 0 14 pH
2. Always use fresh buffers for calibration. Choose buffers that are no more than 3 pH units apart.
3. To obtain the maximum precision, always buffer as close as possible to the expected measured value.
4. Between measurements, rinse electrodes with distilled water and then with the next solution to be measured.
5. Stir all buffers and samples. 6. Avoid rubbing or wiping electrode bulb in order to reduce the
chance of error due to polarization.
pH Calibration and Measurement Refer to the owners guide from the manufacturer of the pH meter being used for detailed information regarding calibration and temperature compensation procedures.
Two-Buffer Calibration (for high precision measurements) 1. Set up the pH meter according to the manufacturers instruction
manual. 2. Ensure that all buffers are at the same temperature (+/- 2oC.) If
samples are at varying temperatures, temperature compensation is recommended. (See pH meter instruction manual.)
3. Select two buffers that bracket the expected pH value. The first should be near the electrode isopotential point (pH 7) and the second near the expected pH of the sample. (e.g., pH 4 or 10.)
4. Rinse the electrode first with distilled water and then with pH 7 buffer. Place the electrode in the pH 7 buffer.
5. Wait for a stable pH 7 reading. Set the pH meter to the pH value of the buffer at its measured temperature.
6. Rinse the electrode first with distilled water and then with the second buffer. Place the electrode in the second buffer.
7. Wait for a stable display. Set the pH meter to the pH value of the buffer at its measured temperature.
8. Calibration is complete. Proceed to pH measurement
Single-Buffer Calibration (for lower precision measurements) 1. Set up the pH meter according to the manufacturers instruction
manual. 2. Choose a buffer that has a value close to the expected pH of the
sample.
3. Rinse the electrode first in distilled water and then in the buffer being used for calibration. Place the electrode in the buffer.
4. Wait for a stable display. Set the pH meter to the pH value of the buffer at its measured temperature.
5. Proceed to pH measurement
pH Measurement
1. Calibrate the electrode as described in previous section. 2. Rinse the electrode with distilled water and then with the sample solution. 3. Place the electrode in the sample. 4. Stir the sample. 5. When the reading is stable, record the pH value.
Electrode Storage and Maintenance Electrode Storage 1. Electrodes 601100 and 601500
Store in the soaking bottle. The soaking solution should be 22.4g KCl dissolved in 100ml pH4 buffer solution or 25g KCl dissolved in 100ml pure water.
2. Electrode 60120B Store with wetting cap kept damp with pH4 buffer or, alternatively, store in a soaking solution.
Electrode Maintenance 3. Inspect the electrode for scratches, cracks, salt crystal build-up,
or membrane/junction deposits. 4. Rinse off any salt build-up with distilled water, and remove any
membrane/junction deposits as directed in cleaning procedures below.
5. Drain the reference chamber, flush it with fresh filling solution and refill the chamber
Cleaning Procedures Soak in mild detergent or dilute 0.1M HCl for 30 minutes
Electrode Reconditioning If the electrode has been allowed to dry for any period of time it may require reconditioning. Soak the electrode in a pH 4 buffer solution for at least 20 minutes. Depending on the dryness of the reference junction, this reconditioning process may require up to a 24 hour soaking period in order to obtain accurate pH readings.
Warranty FLIR Systems, Inc. warrants this Extech Instruments brand device to be free of defects in parts and workmanship for one year from date of shipment (a six month limited warranty applies to sensors and cables). If it should become necessary to return the instrument for service during or beyond the warranty period, contact the Customer Service Department for authorization. Visit the website www.extech.com for contact information. A Return Authorization (RA) number must be issued before any product is returned. The sender is responsible for shipping charges, freight, insurance and proper packaging to prevent damage in transit. This warranty does not apply to defects resulting from action of the user such as misuse, improper wiring, operation outside of specification, improper maintenance or repair, or unauthorized modification. FLIR Systems, Inc. specifically disclaims any implied warra