User manual HANNA INSTRUMENTS PH 21

[. . . ] If the instrument is to be returned to Hanna Instruments, first obtain a Returned Goods Authorization number from the Customer Service department and then send it with shipping costs prepaid. When shipping any instrument, make sure it is properly packaged for complete protection. GENERAL DESCRIPTION pH 20 and pH 21 are basic pH meters designed for simplicity of use in all applications where rapid daily controls are required. These meters are also suitable for educational field, where students begin to approach pH measurements. In addition, pH 21 can also measure ORP (mV) by using a proper ORP electrode (optional). [. . . ] · To temperature compensate the pH reading, measure the temperature of the solution with a ChecktempC or another accurate thermometer. · Press the RANGE key to enter the °C mode and adjust the displayed value by using the arrow keys. TAKING ORP MEASUREMENTS (for pH21 only) · The meter is factory calibrated for ORP (mV) range. Please contact the nearest Hanna Service Center for recalibration, if needed. · Connect an ORP electrode (optional, see "Accessories" section) to the BNC connector on the rear panel (see page 4). · Connect the 12VDC power adapter to the instrument (see page 4) and then to the mains. · Remove the electrode protective cap, then immerse the ORP electrode in the sample to be tested. Note: The electrode should be submerged approximately 4 cm (1½") into the solution. Note: With refillable electrodes, to obtain a faster response unscrew the refill hole cap during measurements. · Shake briefly and wait a few seconds for the reading to stabilize, i. e. The LCD will show the ORP (mV) value. 7 · After measurements, turn the meter off by pressing the ON/OFF key, disconnect the power adapter from the mains and the electrode from the instrument. Note: To perform correct ORP measurements, the surface of the ORP electrode must be clean and smooth. Note: When not in use, the tip of the electrode should be kept moist and safe from any mechanical stress which might cause damage to the glass/platinum junction. pH CALIBRATION For better accuracy the instruments should be calibrated frequently, and however: 1. · Turn the instrument on after connecting the pH electrode and the temperature probe. · Immerse the temperature probe together with the electrode into pH 7. 01 buffer solution or manually set the temperature (see the note here below). Note: The pH electrode should be submerged approximately 4 cm (1½") into the solution and the temperature probe should be located as close as possible to the electrode. Note: If the temperature probe is not used, measure the buffer value with a thermometer, enter the °C mode by pressing the RANGE key and adjust the displayed value by using the arrow keys. · Press the CAL key to enter the calibration mode: the display flashes "pH 7. 01" and the hourglass symbol lights up. TAKING TEMPERATURE MEASUREMENTS · The meter is factory calibrated for temperature range. Please contact the nearest Hanna Service Center for recalibration, if needed. · Connect the HI 7662 temperature probe (optional) to the proper connector on the rear panel (see page 4). · Connect the 12VDC power adapter to the instrument (see page 4) and then to the mains. · Shake briefly and wait a few seconds for the reading to stabilize, i. e. · After measurements, turn the meter off by pressing the ON/OFF key, disconnect the power adapter from the mains and the probe from the instrument. HOLD FUNCTION · To freeze a reading on display, from measurement mode press and hold the HOLD key. [. . . ] Use: food processing. ORP ELECTRODES All electrode part numbers ending with B are supplied with BNC connector and 1 m (3. 3') cable. For a complete list of available pH and ORP electrodes, consult the Hanna General Catalog or visit www. hannainst. com pH ELECTRODES All electrode part numbers ending with B are supplied with BNC connector and 1 m (3. 3') cable. HI 1053B Glass body, triple ceramic junction, conic shape, refillable, combination. HI 1330B Glass body, semimicro, single junction, refillable, combination. [. . . ]