H-4161 – Xylem H-4161 User Manual
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2-6 Installation And Maintenance
H-4161
7. Issue an “
ZD0!” command to collect data from your SDI-12 sensor. The H-4161 monitors and
captures the response. Your SDI-12 sensor should respond with
“Z+nnn.n
8. Issue a “
0M!” command to “measure” the data value collected by the H-4161. The H-4161 should
respond with:
00001
9. Issue a “
0D0!" command to collect the captured data value from the H-4161. The H-4161 should
respond with:
0+nnn.nn
+nnn.nn is the data value captured from your sensor by the H-4161, this value should match the data
value measured by your sensor in Step 7. The value must be between the Min and Max set point settings
of the H-4161 or the output will be clamped at either 4.0mA or 20mA respectively.
Use the following equation to calculate the current which should be output by the H-4161. Compare this
value with the reading displayed by the current meter installed in Step 1. Note, if the loop power is
removed or applied after the data collection sequence of Step 7 was completed, the output of the H-4161
will be a random current value until a new measurement sequence is performed.
where: Xdata = nnn.nn as measured by your sensor
MAX = the Max setpoint of the H-4161
MIN = the Min setpoint of the H-416
1
2.13 Testing with Module Mode = 1 (initiate)
Use the following procedure to verify your H-4161 is working properly. These tests will also
help you understand how the H-4161 works.
1. Make the connections to the +12V power and the 4-20mA output. Connect the sensor to be
monitored to the auxSDI-12 port. Make certain the address of this sensor is “0". If you wish to
experiment with the measure rate or other settings, connect a data logger to the primary SDI-12
data port. Your loop power source, loop receiver and the H-4161's output should all be connected
in series. In addition, temporarily connect a current meter in series with the 4-20mA loop.
Make certain there is 5.5 to 35V across the 4-20mA output terminals.
Make certain the H-4161 is receiving +12V power from the SDI-12 data bus.