To perform a 1-point adjustment to the temperature measurement of the HMP110, HMP113, or HMP110T using serial line, you need:
- Vaisala USB cable (item code 219690)
- PC with a terminal application
- One known and stable temperature reference
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Connect the USB cable to the PC, but do not connect it to the probe yet.
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Remove the filter from the probe and insert the probe in the temperature reference.
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Start a terminal application and set the correct connection settings. The default serial settings are 19200 8 N 1. Remember to check which COM port the USB cable is using.
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Wait for 20 … 40 minutes for the temperature to stabilize.
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Start the terminal session and connect the USB cable to the probe. If your probe is in the analog output mode, you need to press ENTER a few times to start it in
RS-485 mode.
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Verify that the connection works by giving the ? command.
?
If the probe does not respond with device information:
- Disconnect the USB cable from the probe and retry. If your probe is in the analog output mode, press ENTER a few
times immediately after connecting the USB cable.
- Try the ?? command in case the probe is in POLL mode, open the line using OPEN command if necessary.
- Check your serial line settings and cable connections.
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When your serial connection is working, use the L command to see the current user adjustment parameters.
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Use the ERRS command to see that no errors are active.
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Give the CT command, with the temperature value of the reference as a parameter.
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Check with the L command that the user adjustment parameters have changed.
If you wish to remove the effects of T calibration (returning the T measurement of the probe to the factory calibrated state).