User Guide Model PH210 pH / ORP / Temperature Meter
Introduction Thank you for selecting the Extech PH210 pH/ORP/Temperature meter. This microprocessor‐ based device with tactile push‐buttons is battery operated and ideal for field use. The PH210 simultaneously displays pH or mV (ORP) and solution temperature measurements. This meter is shipped fully tested and calibrated and, with proper use, will provide years of reliable service. Features LCD display shows pH or mV (ORP) and solution temperature simultaneously pH measurement range 0 to 14.
Getting Started 1. Calibrate the instrument often, as described in a later section. Note that only a pH calibration is required; mV (ORP) is calibrated as a by‐product of the pH calibration. o o 2. Set the unit of measure for solution temperature ( C or F) as described in the Temperature Units Selection section of this guide. 3. Determine if Automatic or Manual temperature compensation will be employed. Refer to the Temperature Compensation section of this guide for details. 4.
Measuring pH Important: Electrodes and temperature probes should always be rinsed before and between samples with distilled water to remove all traces of storage solution, process media, or previous test solution. 1. Connect the pH electrode to the meter (BNC connection at bottom of meter). 2. Optionally connect the temperature probe (Extech model 850188 only) to the jack at the bottom of the meter. This temperature probe is used for automatic temperature compensation (ATC).
Automatic (ATC) and Manual Temperature Compensation The PH210 automatically compensates (ATC) for solution temperature deviations when the Model 850188 temperature probe (inserted at bottom of meter) is placed in the measurement solution. The temperature of a solution is displayed on the meter’s lower LCD line. To manually compensate for solution temperature deviations a separate thermometer must be placed in the solution to monitor the solution’s temperature; then proceed as follows: 1.
MIN/MAX Data Recording (REC) mode This instrument has the ability record the highest (MAX) and the lowest (MIN) readings recorded. Readings are retained even after the instrument is switched OFF. 1. Momentarily press the REC button (REC will be displayed at the upper right). 2. Press REC again. REC/MAX will be displayed along with the maximum reading. 3. Press REC again to display the MIN reading. REC/MIN will display along with the minimum reading. 4.
Battery Replacement The 9V battery that powers the instrument requires replacing when the battery icon flashes on the display. To replace the battery follow the steps below: 1. 2. 3. 4. 5. Disconnect the electrode/probe from the instrument. Open the rear battery compartment using a screwdriver to remove the two Phillips head screws that secure the compartment. Carefully remove the old battery from the compartment lid chamber and gently unsnap the battery’s terminals from the wired (red/black) connectors.
Troubleshooting an Electrode Symptom Long response time or reading drift Dry Bulb Static Charge Same readings in different buffers and samples Erratic LCD display Cause Clogged Junction Recommendation Soak in 4.07 M Potassium Chloride (KCl) @ 60oC for 30 minutes. Soak in 0.1 M HCL overnight. Strong Alkaline measurement Deteriorated Gel layer Replace electrode. Protein coating on electrode Soak in 1 gm Pepsin dissolved in 100ml surface of 0.1 m HCL for 30 minutes or as needed.
