Hanna Calibration Check PH Meter HI 223
A ph electrode when it is properly manufactured and is kept clean will retain its physical characteristics for a long time. A common problem associated with ph measurements is the use of a ph electrode that has not been properly cleaned. This is very important because during calibration the instrument assumes that the electrode used is clean and the standardization curve created during the calibration process will remain the same until the next calibration. Ph meters on the market today will allow an offset of approximately +/- 60 mV. The deviation from 0 mV is not unusual; in fact, it represents the true characteristics of the pH electrode. The deviation from 0 mV becomes a problem if it is the result of calibrating a dirty electrode. The pH measured by a dirty electrode changes over a period of time. This results from the residue on the pH electrode bulb dissolving into the solution and the electrode gradually returning close to its true characteristics. The resulting pH measurements based upon the calibration of a dirty electrode will then be incorrect.
Hanna's HI 221 and HI 223 compare the characteristics of the pH electrode from one calibration to the next. In cases of a large variances in electrode condition that can only be the result of a dirty electrode, these meters alert the user that the electrode needs to be properly cleaned prior to the calibration process.
Enhanced Calibration Messages: During calibration, the user is warned if one or more parameters are not suitable to perform an accurate calibration.
Electrode Condition on LCD Display: Determined from the electrode offset and slope.
Electrode Response Time on LCD Display: Determined from electrode performance during calibration.
Calibration Alarm Time Out: Can be programmed from 1 to 7 days or can be disabled.
Last Calibration Date and Data
Instrument ID Number
Real Time Clock
PH Range: -2.00 to 1600 or -2.000 to 16.000
mV Range: +/- 999.9, +/-2000
Degree C Range: -20.0 to 120.0
PH Accuracy: +/- 0.01; +/- 0.002
mV Accuracy: +/- 0.2 (+/-699.9); +/- 0.5 (+/-999.9); +/- 1 (+/-2000)
Degree C Accuracy: +/- 0.4
PH Resolution: 0.01; 0.001
mV Resolution: 0.1(+/-999.9 mV); 1(+/-2000 mV)
Degree C Resolution: 0.1
Calibration Check: Yes
PH Calibration: Automatic 1 or 2 points (pH 1.68, 4.01, 6.86, 7.01, 9.18, 10.01, 12.45)
Temperature Compensation: Manual or Automatic from -20.0 to 120.0 degrees C
PH Electrode: HI 1131P glass body, single junction refillable cell, BNC + pin (included)
Temperature Probe: HI 7669/2W stainless steel probe (included)
PC Interface; Opto-isolated RS232
Logging: 500 pts.
Power: 12 VDC adapter (included)
Environment: 0 to 50 degrees C (32 to 122 degrees F) 95% RH
Dimensions: 240 x 182 x 74 mm ( 9.4 x 7.1 x 2.9 inches)
Weight: 1.1 Kg (2.5 lb)
Warranty: 5 years