Xylem H-3521 - Manual (Page 40)

5-10 SDI-12 Command and Response Protocol
H-3521
5.9 Extended Set Current Stage Command
The H-3521 processes the pressure sensor input and computes Pressure in PSI units. Stage is
computed with a Stage = m * Pressure + b equation. During installation it is convenient to
quickly set the H-3521's Stage reading to match the current stage, elevation or pressure of the
water as determined by a staff gauge or other datum. This command causes the H-3521 to make a
fresh measurement and automatically update the Offset (b) term as needed to produce the desired
Stage
.
Command Response Description
"aXSCSddd!" “a0061<cr><lf>" Set current Stage
Where: a is the sensor address ("0-9", "A-Z", "a-z", "*", "?").
XSCS are upper case characters.
ddd is the new current stage value.
Example of a H-3521 Extended "Set Current Stage" command:
Command Response Time Values Description
"aXSCS2.3!" "a0041<cr><lf>" 4 sec 1 Set the Stage to 2.3
Subsequent Command Response Description
"aD0" a+1.80<cr><lf> The new Offset