11 Probe Replacement
11.1 Every pH probe gradually loses its sensitivity as it’s being used. A typical service life of a pH
probe is 1-2 years depending on many factors such as frequency of use, nature of test
samples, and how well it is maintained, etc. Apera Instruments recommends replacing the
pH probe after one year of frequent use to guarantee the optimal performance of a pH meter.
11.2 How to replace the probe: Twist off the probe ring, unplug the probe, plug in new probe (pay
attention to probe’s position), and twist on the probe ring.
11.3 The model numbers of the replacement probes that are compatible with the PH60 Series
Meters:
• AI1201 PH60-E (Regular pH glass bulb probe)
• AI3711-E PH60-DE (Double-junction pH glass bulb probe)
• AI1205 PH60S-E (Spear pH probe for solids/semi-solids pH testing)
• AI1203 PH60F-E (Flat pH probe for surface pH testing)
• AI1207 ORP60-E (ORP probe)