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Issue link: https://wardsworld.wardsci.com/i/1542838
Find on wardsci.com pH Best Practices Keep the electrode hydrated Why — Drying out the electrode leads to drifting pH values, slow response times, and incorrect measurements. Fix — "Revive" a dry electrode by submerging the bulb and junction in pH storage solution for at least one hour. Rinse, do not wipe your electrode Why — Wiping the pH glass can produce a static charge which interferes with the pH reading of the electrode. Fix — Simply rinse the electrode with distilled or deionized water (DI). Blot (do not rub) with a lint-free paper towel (e.g. Kimwipes®) to remove excess moisture. Store your electrode in storage solution Why — Storing in deionized water (DI) causes ions to leach from the glass membrane and reference electrolyte resulting in a slow and sluggish response. Fix — Store your electrode in storage solution. Clean your electrode regularly Why — Deposits can form on the electrode during use, coating the sensing glass. This can lead to erroneous calibrations and readings. Fix — Clean the electrode using a specially formulated cleaning solution for pH electrodes— ideally one that's developed for your application. Calibrate often Why — All pH electrodes need to be calibrated often for best accuracy. Fix — The frequency of calibration depends on how accurate you want to be - daily calibration is ideal. Pick the right electrode for your sample Why — General purpose electrodes are functional for a wide variety of applications but not ideal for all samples. Fix — Based on your sample you may require an electrode designed for food, high/low temp, non-aqueous, or other types of samples. Open or loosen the fill hole cap Why — A closed electrode fill hole may lead to slower stabilization times. Fix — Loosen or remove the fill hole cap. Remember to put it back when storing the electrode. (Not applicable for non-refillable electrodes). Keep the electrolyte level full Why — Electrolyte flows out from the reference junction over time. Low electrolyte levels may cause erratic readings. (Not applicable for non-refillable electrodes) Fix — Ensure that your electrode fill solution level is no less than one-half inch from the fill hole cap. Properly submerge your electrode Why — Both the pH sensing glass and reference junction need to be completely immersed in order to function properly. Fix — Add enough sample to submerge both the junction and sensing glass. Inspect your electrode Why — Over time, the sensing portion of the glass becomes less responsive and will eventually fail. Damage from use is also possible. This will cause erroneous readings. Fix — Check your electrode for damage and perform a slope and offset calculation. Reference blog for instructions. + ward ' s science 5100 West Henrietta Road • PO Box 92912 • Rochester, New York 14692-9012 • p: 800 962-2660 • wardsci.com