User Guide

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Symmetrical mode:
For noisy electrical environments, the alpha pH 190 controller offers
Symmetrical Mode operation. To take advantage of Symmetrical
operation, you must have an electrode with a solution ground
(potential matching) pin, such as the EC-ARGTSO-05B or EC-
100GTSO-05B.
If your electrode does not have a solution ground, be sure to set the
controller to Asymmetrical mode.
Symmetrical mode avoids grounding the reference electrode by
reconfiguring the input to a floating differential mode. The electrical
noise appears equally on the pH and reference electrodes, and is
therefore rejected by the operational amplifier.