Advanced operation
This section gives instructions about menu navigation and available options. Change parameter-specific settings through the Full Access Options menu.
The settings that can be changed are shown in
Table 1 .
Table 1 Parameter-specific settings
Setting
Measurement Options
Options
• Resolution
• Upper and lower range limits
Calibration Options calibrated again. To correct the probe calibration and status indicator, calibrate the probe (refer to
Calibration
on page 3).
• Buffer set
• Buffer set values (if Custom Buffer Set selected)
• Reminder
• Minimum Cal points
• Slope limit
Check Standard Options
• Standard (temperature compensated buffer or custom at 25 °C (77 °F))
• Reminder
• Acceptance criteria
• Standard value at 25 °C (77 °F) (if custom standard selected)
Units
• pH
• mV
Change measurement options
Methods are groups of default or user-defined settings related to specific applications. If the meter is set to the default method, a prompt for a new name method shows. The settings are saved with this name to identify them from the default method settings, which cannot be changed. Use a saved method as an alternative of many adjustments to the individual settings. Changes made to a user-defined method are automatically saved with the existing name. Save different methods for the same probe on each meter.
1. Make sure that a probe is connected to the meter.
2. Push and select PHC805 Settings.
3. Select Modify Current Settings.
4. Select Units. Select pH (default) or mV.
Note: Use the mV option to find the probe offset in a pH 7 buffer or to measure the slope. Both units show when the Detail Display mode is selected.
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5. Select Measurement Options and update the settings:
Option
Resolution
Description
Set the resolution:
• 0.1 pH—Fast
• 0.01 pH—Fast (default)
• 0.01 pH—Medium
• 0.01 pH—Slow, or
• 0.001 pH—Slow
Measurement
Limits
The resolution has an effect on the number of decimal digits and the stabilization time. More stabilization time is necessary for higher resolution measurements. Slower stabilization times give higher accuracy measurements.
Set the measurement limits—Lower limit (default: 0.00 pH) or Upper limit
(default: 14.00 pH).
Set the measurement limits to agree with the permitted values for the sample. When the measurement is above the upper limit setting or below the lower limit setting, the meter shows an "Out of limits" message. This message is an alert to a possible problem with the process conditions.
6. If prompted, enter a name for the new method settings. Other changes made to the settings of an existing method are automatically saved with the same method name.
7. Push EXIT until the meter goes back to the measurement mode.
Change calibration options
1. Make sure that a probe is connected to the meter.
2. Push and select PHC805 Settings.
3. Select Modify Current Settings.
4. Select Calibration Options and update the settings:
Option
Buffer Set
Description
Sets the temperature compensated buffer set for calibration:
• Color Coded—4.01, 7.00, 10.01 (default)
• IUPAC—4.01, 7.00, 10.01, 12.45
• DIN—4.65, 9.23
• IUPAC—4.01, 6.86, 10.01, 12.45
• IUPAC—4.01, 6.86, 9.18, 12.45
• IUPAC—4.01, 7.00, 9.18, 12.45
• Custom Buffer Set (refer to
Table 2 )
Custom buffer sets are characterized at 25 °C (77 °F).
Buffer set values show on the Calibration Options screen.
Note: Measure only the minimum calibration points specified in Minimum
Cal Points to complete a calibration.
Sets the buffer values if Custom Buffer Set is selected (refer to
Table 2 ).
Buffer Set
Values
Minimum Cal
Points
Slope Limit
Sets the minimum number of calibration points that are necessary to complete a calibration—1 (default), 2 or 3.
Sets the slope limit—1% to 20% (acceptable slope criteria, default = 15%).
Set the slope between the set limits for a correct calibration.
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5. Select the Calibration Reminder and update the settings:
Option
Reminder
Repeat
Expires
Description
The meter makes a sound when a calibration is necessary and at the selected interval—Off (default), 2 h, 4 h, 8 h, 2 d, 5 d or 7 d.
Calibration expires after the selected time—Immediately, Reminder +
30 min, Reminder + 1 h, Reminder + 2 h or Continue Reading.
Note: The meter cannot read samples after calibration has expired unless
Continue Reading is selected.
6. If prompted, enter a name for the new method settings. Other changes made to the settings of an existing method are automatically saved with the same method name.
7. Push EXIT until the meter goes back to the measurement mode.
Table 2 Custom buffer sets
Description Buffer set values
Std1 to
Std5
Option
1.09 pH—25 °C Pre-set temperature compensated buffer values.
1.68 pH—25 °C
4.01 pH—25 °C
4.65 pH—25 °C
6.86 pH—25 °C
7.00 pH—25 °C
9.18 pH—25 °C
9.23 pH—25 °C
10.01 pH—
25 °C
12.45 pH—
25 °C
Note: It is necessary for selected standards to be different by a minimum of 2 pH units. For example, if
1.09 pH is selected for the first standard, the second standard must be different by at least 2 pH.
Standards that do not meet this minimum will show gray on the screen and will not be selectable.
Custom Buffer Custom buffer value.
Range = 2.000 pH to 14.000 pH.
Custom buffer values are not temperature compensated. Custom buffers must be read at
25 °C (77 °C).
No Buffer Select this option for undefined standards.
Change check standard options
1. Make sure that a probe is connected to the meter.
2. Push and select PHC805 Settings.
3. Select Modify Current Settings.
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