Xylem H-4161 - Manual (Page 15)

H-4161
Installation And Maintenance 2-7
Use the Transparent SDI-12 mode of your data recorder to issue and monitor the following SDI-
12 commands
1. Set Module Mode = 1 (See chapter 3).
2. Program the Max and Min setpoint as needed for your application, set the Monitored
Parameter setting as needed.
3. Check to see if the H-4161's 4-20mA output is working by using the “Set Milliamp”
command.
Issue a “ 0XSM10.0!” command.
The H-4161 should respond with: I-out=10.0
This sets the H-4161s output to 10.0mA . Check to see if the current meter you
installed in Step 1 shows 10.0 mA flowing in the loop.
Note: your setting will soon be overwritten when the next initiated measurement is made.
Experiment with different current settings using the XSMnnn command. Make certain
your loop works at the 4.0 and 20.0 mA endpoints. Experiment with the “aXSCSddd”
command to make certain your Max and Min settings are correct.
4. The H-4161 should be making measurements to the sensor attached to the auxSDI-12 port in a
tight loop. Check the 4-20mA output for the expected response.
5. Change the Measure Rate as needed. Check for the expected response with an oscilloscope or
other means to detect when a measurement is initiated.
2.14 Transparent Mode
When the Module Mode = 1 (Initiate), the H-4161 actively initiates measurements and collects
the response from the sensor attached to the auxSDI port. During setup and testing it may be
useful for the user to access the sensor attached to the auxSDI port without changing the wiring
or connectors. When activated (see Chapter 3), the Transparent mode causes the H-4161 to stop
making measurements on the auxSDI port and to make a virtual connection between the primary
and auxSDI ports. While the Transparent Mode is active, all communication to/from the H-
4161's address is passed thru to the auxSDI port. The “aM!”, “aD0!” and other internal
commands of the H-4161 are disabled and the H-4161 is essentially replaced by the sensor
attached to the auxSDI port.. The Transparent Mode is automatically deactivated when the H-
4161 detects an access to any sensor address other than its own. Note: the sensor address
character of each command is forced to “0" by the H-4161 before being forwarded to the auxSDI
port.