Preparing Chloride Calibration Solution
The following recipes are provided for preparation of 10 and 1000 mg/L chloride reagents.
It is important to note that some of the chemicals required for these solutions could be hazardous under some
conditions. It is the responsibility of the user to obtain and study the MSDS for each chemical and to follow the
required instructions with regard to handling and disposal of these chemicals.
You will need: Solid sodium chloride or a certified 1000 mg/L chloride solution from a supplier, magnesium
sulfate, high purity water, a good quality analytical balance, 1000 ml volumetric flask, an accurate 10 ml
measuring devices, and 1000 ml glass or plastic storage vessels.
1000 mg/L
standard
: Accurately weigh 1.655 grams of anhydrous sodium chloride and transfer into a 1000 ml
volumetric flask. Add 0.5 grams of anhydrous magnesium sulfate to the flask. Add 500 ml of distilled or deionized
water to the flask, swirl to dissolve all of the reagents, and then dilute to the volumetric mark with water. Mix well
by repeated inversion and then transfer the 1000 mg/L standard to a storage bottle. Rinse the flask extensively
with water prior to its use in the preparation of the 10 mg/L standard. Alternatively, simply add 0.5 grams of
magnesium sulfate to a liter of a 1000 mg/L chloride standard from a certified supplier.
10 mg/L standard
: Accurately measure 10 ml of the above 1000 mg/L standard solution into a 1000 ml
volumetric flask. Add 0.5 grams of anhydrous magnesium sulfate to the flask. Add 500 ml of distilled or deionized
water, swirl to dissolve the solid reagents, and then dilute to the volumetric mark with water. Mix well by repeated
inversion and then transfer the 10 mg/L standard to a storage bottle.
TROUBLESHOOTING TIPS
Typical working life for chloride sensors is approximately 3-6 months depending on use, storage and
maintenance. Proper storage and maintenance generally extends the sensor’s working life.
If you get error messages during a chloride calibration, check the following:
1. Ensure the chloride solutions are good and not expired
2. Ensure that the chloride sensor is installed in the correct port of the cable and the correct ISE is enabled in
the Sensor Setup menu.
a. If using a chloride sensor in a 6051020 cable, ensure the sensor is installed in port 1.
b. If using a chloride sensor in a 60510, 6051020 or 6051030 cable, chloride should be enabled in ISE1
of the instrument’s Sensor Setup menu.
c. If using a chloride sensor in a 6051010 or Quatro cable, check to see if the chloride sensor is
installed in port 1 or port 2. If the chloride sensor is installed in port 1, enable chloride in ISE1 of the
Sensor Setup menu. If the chloride sensor is installed in port 2, enable chloride in ISE2 of the Sensor
Setup menu. Note: If using with a pH or ORP sensor, it is recommended to install the pH or ORP
sensor in port 1 and the chloride sensor in port 2.
3. If using a 6051010 or Quatro cable, you must have a sensor installed in port 1 for port 2 to operate.
Additionally, ensure that the sensor installed in port 1 is in good working order. In 6051010 and Quatro
cables, the sensors installed in port 1 and port 2 use the reference from the sensor installed in port 1 only.
Therefore, if the sensor installed in port 1 is not working properly, the readings from the sensor installed in
port 2 will be erroneous as well.
4. If you continue to get error messages during calibration, clean the sensor.
5. If you continue to get error messages during calibration, soak the sensor in 1000 mg/L chloride standard for
several hours or overnight.
6. If you suspect port contamination, follow the instructions in the Cleaning a Sensor Port section.
7. If you continue to have trouble calibrating the chloride sensor, contact your local YSI Representative or a YSI
Authorized Service Center.
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