Sensor Input Configuration
The Ratio:Guard monitor comes congured for one or two pH sensors and one EC sensor. Two options
are oered for each input; Digital Pulse input (legacy Anderson) or 4-20ma Analog. It is fully
compatible with any Anderson sensors you may already have.
A digital pH input provides greater resolution and accuracy but requires our P/N 11627 Signal
Converter. If you already have one this should be your setting.
The digital EC input works directly only with an Anderson digital EC electrode and provides greater
resolution than a 4-20ma analog input. But for greatest reliability the best choice is a contactless
toroidal EC sensor. It is more expensive, but provides superior reliability and much lower
maintenance.
With an analog input you must also enter the EC range limit. This is the 20ma calibration point of
your EC sensor. Allowable values are 2.0-10.0 milliSeimens (mS). The lower this value is, the ner the
resolution of the EC reading.
Cancel
The default setting is No
Input Assigned. Otherwise
the cursor will show the
current setting.
Enter
The EC Range Limit is displayed only if the
4-20ma analog input is selected.
This is the full scale (20ma) EC value and
depends on how the EC sensor is calibrated.
Set Input
Cancel
Set Input
Enter
4-20ma ?
No
Yes
4-20ma ?
Cancel
Enter
Enter
No
Yes
Enter
Enter
Cancel
Enter
Set Input
Enter
Set Input
Cancel
Enter
Enter
Enter
Enter
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