H-4280 – Xylem H-4280 User Manual

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2-4 Installation And Maintenance

H-4280

2.9 Testing

For preliminary testing a simple potentiometer can be used to simulate one or more sensors. Connect one

end of the potentiometer resistor to a ground terminal and the other end to the +5Vref terminal. Connect

the potentiometer wiper to one of the input channels. Make several measurements while adjusting the

potentiometer and check for the expected results.

2.10 “XTEST”

The “XTEST” command is used for installation or production testing and requires the use of a H-4191

Sidekick interface and a PC. This command causes the H-4280 to transmit unsolicited real-time data for

testing purposes. The test mode is used to help troubleshoot the installation by providing a continuous

readout of measurement data. This is not compliant with the SDI-12 specification and is not used with data

loggers.

To activate the test mode, send the command “aXTEST!” from the PC. The H-4280 will enter the test

mode and make and print continuous measurements. The test mode is exited by sending a break or any

new command on the SDI-12 bus. For example:

0: +1.202 +3.222 +1.234 +2.345 +2.677 +3.333 +1.202 +1.202