Unknown serial settings, Error state, Error state on pa – Vaisala DMT152 User Manual
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User's Guide _______________________________________________________________________
60 ___________________________________________________________________ M210865EN-F
Unknown Serial Settings
If you are not sure what the serial settings of your transmitter are, follow
the steps below to view and change them.
1.
Make sure there are no other transmitters on the serial line.
2.
Provide the transmitter with a 9 V supply voltage. This voltage is
enough to start it in the error state.
3.
Connect to the serial line using the error state serial line settings
19200 N 8 1.
4.
Give the ? command to view the transmitter settings, including the
serial settings and address. For an output example, see section
Show Device Information on page 35.
You may have to give the command several times if there are
characters in the buffer.
5.
If necessary, set new serial line settings using the SERI command.
For instructions on using the command, see page 42.
Error State
If the voltage supplied to the DMT152 is too low for reliable operation,
or fluctuates heavily, or there is some serious problem that prevents
measurement, the DMT152 will enter an error state. The error state is
indicated by the following:
- Analog current output at 0 mA or 4 mA (according to selected range)
- Analog voltage output at 0V
- Serial line outputs asterisk characters "*" instead of measurement
data. For example:
Tdf=****** 'C H2O=****** ppm
The analog output levels for the error state are configurable using the
AERR command; see section Malfunction Alarm on page 41. Note that
the asterisk characters on the serial line may also appear during the
startup procedure.
When the transmitter is in the error state, it will use the default serial
interface settings, regardless of the currently set serial interface mode. If
you have set a different mode with the SERI command, you will have to
set your terminal program to the default settings of 19200 N 8 1 (also
listed in Table 4 on page 32) before you can connect to the transmitter in
error state.