GF Signet pH-ORP Buffer Calibration Kit - Manual (Page 2)

Most common errors associated with buffer calibration
1. Failure to compensate for the buffer value at the actual temperature; see buffer bottles for temperature corrected
values.
2. Accepting a calibration value before the sensor has had time to fully respond.
• This also occurs as a result of a warm pH sensor being placed in a cool buffer solution; full stabilization and a
correct pH reading will not occur until all components of the pH sensor and the buffer have reached the same
temperature.
3. Some automatic buffer calibration features, such as the Signet EasyCal feature, help eliminate these errors by
identifying and temperature correcting the calibration buffer and not allowing the calibration procedure to be
completed until a stable reading has been reached.
When to calibrate:
•
When the sensor is new and initially installed.
• When the sensor is cleaned for regularly scheduled maintenance.
Caution:
•
Always wear protective gloves and appropriate eyewear when using calibration solutions.
• In rare cases, calibration solutions may come in contact with skin or eyes. Rinse solution off of skin or out of eyes
by fl ushing with tap water for 5 minutes.
Problem Suggested Solution
Hard Coatings Use a dilute acid solution (HCl solution of 5% or less). If the electrode has been used in applications
with a pH value higher than 7 pH, soak the electrode for 2 to 5 minutes.
Use a dilute alkaline solution (NaOH solution at 5% or less) if the electrode has been used in
applications with pH values less than 7 pH, soak the electrode for 2 to 5 minutes.
Alternating immersion in acidic and alkaline solutions may be necessary for thorough cleaning.
A soft bristle brush, like a toothbrush, may be used to remove coatings.
Soft Coatings Spray or vigorously stir the electrode with a mild detergent (such as dishwashing liquid)
Chlorine bleach can also be used.
Oily or Organic Coatings Spray or vigorously stir the electrode with a mild detergent or an appropriate solvent that will not
attack the materials of construction. (isopropyl alcohol or similar)
ORP Platinum Coating Gently wipe the electrode surfaces with a paper towel.
After Cleaning Always rinse the electrode with water after cleaning.
Soak the electrode in a pH 4 buffer (with KCl if available) for at least 10 minutes after cleaning.
Sensor Cleaning
Replacement Parts and other accessories:
Mfr. Part No. Code Description
3822-7004 159 001 581 pH 4 buffer solution, 1 pint (473 ml) bottle
3822-7007 159 001 582 pH 7 buffer solution, 1 pint (473 ml) bottle
3822-7010 159 001 583 pH10 buffer solution, 1 pint (473 ml) bottle
3-0700.390 198 864 403 pH buffer kit (1 each 4, 7, 10 pH buffer in powder form)
3-2700.395 159 001 605 Calibration kit ; includes 3 reusable polypropylene buffer cups, one sensor stand, 1
pt pH 4 buffer solution, 1 pt pH 7 buffer solution
Special Request NIST Traceable Certifi cate
3822-7115 159 001 606 20 gm bottle Quinhydrone for ORP calibration
Georg Fischer Signet LLC, 3401 Aerojet Avenue, El Monte, CA 91731-2882 U.S.A. • Tel. (626) 571-2770 • Fax (626) 573-2057
For Worldwide Sales and Service, visit our website: www.gfsignet.com • Or call (in the U.S.): (800) 854-4090
3-2700.095 Rev. A 12/08 © Georg Fischer Signet LLC 2008 Printed in U.S.A. on recycled paper