Accumet XL 20, Руководство пользователя

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Ion Operation:
Direct Reading Methods
XL25, 50 and 60 meters
There are two direct reading methods:
Direct Reading with Standards and
Direct Reading with Blank Offset.
These types of measurements allow you to directly read the concentration of your sample after
standardizing the meter with ion standards of known values or blank values.
Direct Reading with Standards
This is the most common method of ion measurement. You can directly read the concentration of
the sample after standardizing the meter with ion standards. An ionic strength adjuster (ISA) is
added to both the standards and the sample. Two to five standards are used to standardize the
meter. The standards should bracket the expected value of the sample.
To Standardize the Meter Using Direct Reading with Standards
You must use a minimum of two standards to standardize the meter. Make sure you have
selected “Direct Reading with Standards” on the Ion Setup screen.
1. Add ionic strength adjuster to your standard.
2. Immerse your rinsed electrode(s) into the standard solution and stir gently.
3. Touch the
Standardize button on the Ion Measure screen to access the standardization
screen.
4. Touch Clear if necessary to remove a previous standardization. If the screen says “Not
Standardized,” proceed to step 5.
5. The screen will flash each standard icon once, then a numeric keypad will appear. Using
the displayed keypad input the value of the standard that you are using to standardize the
meter. Touch
Enter to accept this value. The meter now shows the value of the standard
solution in the flashing beaker.
6. Wait until Stable* appears on the screen. Press Confirm button once to confirm the
standardization. To manually override the stability requirement, press Confirm before the
stable message appears after the ion beaker starts flashing with the standard value.
7. Touch Standardize and repeat steps 3-7 with up to 5 standards. A minimum of two
standards is required to standardize the meter in this mode.
8.
* Please note that STABLE will only appear if you have completed a successful two point calibration.
Updating the standardization is not possible. Once five point standardization is complete, if you
press the
Standardize icon the meter will prompt the message to clear the previous
standardization.
If the meter has not been standardized with at least two standards, a series of dashes will appear
in place of a measurement value.