5 subst aeration, 6 number of stages, 11 inputs – Hach-Lange RTC103 N-Module User Manual
Page 50: 1 min inflow, 2 max inflow, 3 0/4 to 20ma, 4 min recirculation, 5 max recirculation, 6 0/4 to 20ma, 7 q reci ratio
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