Lufft CHM 15k Nimbus, Manual

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Communication RS485 & Ethernet
Revision R09, November 2016 37
set 16:UNT=ft<CR><LF>
all range data in a telegram will be indicated in feet (ft) instead of meter (m).
Since
Unit(m/ft) provides a switching option,
<STX>set 16:Unit(m/ft)=ft;2A<CR><LF><EOT>
is output for confirmation. 2A is the checksum value of the response telegram.
8.2.3 Change in Baud Rate
Changes in the baud rate are a special setting option. To make a change, pro-
ceed as described in chapter 8.2.2. For example, by triggering a
set<SPACE>16:Baud=4<CR><LF>
command, you will set the baud rate “4”, it is 19,200 Baud, for the RS485 sensor
16, „RNO=16“, see table 4. Table 6 shows all baud rate numbers and their
assigned baud rate values.
Immediately after the set command, the interface will be set to the new baud
rate. In case of a false baud rate setting with consequential communication
errors afterwards, it is not possible to reverse this setting as usual because of fail-
ure to establish normal communication. It will be reset automatically to the
default baud rate specified by parameter
BaudAfterError after 30 seconds,
which is the standard value of TimeOutRS485(s) . The standard value of
BaudAfterError is 3, which means 9,600 bits per second. If this baud rate still
proves too high, a different desired baud rate can be set as the default rate
before product shipment or by service personnel.
8.2.4 Reboot, restart and reset
By triggering a
set<SPACE>16:Reset=1<CR><LF>
command, the build in processor board is instructed to immediately perform a
reboot.
A restart procedure takes less than a minute. Before or unless it has finished,
communication with the CHM 15k is not possible. The same applies to continu-
ously ongoing telegram outputs.
Baud rate no. Baud rate [bits/s]
(0) (1,200)
(1) (2,400)
2 4,800
3 9,600
4 19,200
5 38,400
6 57,600
7 115,200
Table 6: Baud-rate-number-to-baud-rate assignments. Baud rates 0;1 are not
specified within the time limits.