Chapter 1 Introduction
Thank you for your purchase of the Orion Star A111 benchtop pH or Star A121 portable pH meter. These meters
are capable of measure pH, raw millivolts (mV), relative millivolts (Rmv), oxidation-reduction potential (ORP) and
temperature.
The Orion Star A111 benchtop pH meters are IP54-rated. The Orion Star A121 portable pH meters feature a
waterproof, IP67-rating.
Please read this reference guide thoroughly. Any use outside of these instructions may invalidate your warranty and
cause permanent damage to the meter.
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Thermo Scientific Orion Star A111 Benchtop and Star A121 Portable pH Meters