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INTENDED USE AND GENERAL INTRODUCTION
The models 3672, 3673 and 3675 are precise instruments for the measurement and control
of pH and mV (ORP).
Two output relays are provided in the model 3675 for ON/OFF control. The isolated 4-20
mA output current of the model 3675 covers the input control range of 0 to 14 pH and 0 to
1400 mV.
A front panel programmable HIGH/LOW ALARM relay is provided in the models 3672
and 3673.
The isolated 4-20 mA output of the model 3672 can be set for a input control span of any
2 to 14 pH (200 to 1400 mV), via the front panel CONTROL SET POINT and SPAN ADJ
controls. The output 4-20 mA current can be selected for increasing or decreasing values
for increasing pH and mV (ORP) inputs. The isolated 4-20 mA output current of the
model 3672 covers the input control range of 0 to 14.00 pH and ±1999 mV.
The output pulse frequency of the model 3673 is proportional to the ion concentration,
over a preset proportional band of 2 pH and 200 mV. The pulse frequency output can be
selected for increasing or decreasing pulse rate for increasing pH and mV (ORP) inputs.
The maximum pulse frequency can be adjusted by the front panel PULSE RATE
ADJUST control. The pulse frequency output of the model 3673 covers the input control
range of 0 to 14.00 pH and ±1999 mV.
