Lufft CHM 15k, User Manual

Page: 33 / 73

Operating Manual CHM 15k R13 / 07-2019
Communication via RS485 & Ethernet 33
8.3 Data query RS485
When running, the CHM 15k operates in one of the transfer modes shown in Table 7.
Transfer mode Meaning
0 Data telegrams are only output on a specific request (polling mode)
1 Automatic output of the standard data telegram
2 Automatic output of the extended data telegram
3 Automatic output of the raw data telegram
4 … 9
Automatic output of further predefined data telegrams
Table 7 Summary of transfer modes.
The transfer mode can be changed with the Set command
set <RS485Number>:TMO=x
as described in section 8.2.2 Setting a parameter or via direct input in the web interface.
Thus, with the command
set<SPACE>16:TransferMode=1<CR><LF>
the automatic output of the standard data telegram is activated for the device with RS485 number 16
(default setting valid at the time of delivery).
8.3.1 Polling mode
The command
set<SPACE><RS485Number>:TransferMode=0<CR><LF>
sets the polling mode and thereby any previously running automatic telegram output is issued. With the
three commands
get<SPACE><RS485Number>:S<CR><LF>
get<SPACE><RS485Number>:L<CR><LF>
get<SPACE><RS485Number>:A<CR><LF>
the standard data telegram (S), extended data telegram (L) or raw data telegram (A) are called up once
only. For the format of the respective data telegram, see
0
Standard data telegram to 8.3.5 (Table 8 , Table 9 , Table 12).
Additional telegrams
The Nimbus hardware platform of the CHM 15k (starting in 2011) supports further
user telegrams.
In addition to the characters {S, L, A}, numbers are also supported. With S = 1, L =
2, A = 3, the first three numbers are predefined.
8.3.2 Automatic output mode
With the command
set<SPACE><RS485Number>:TransferMode=1<CR><LF>
the automatic mode is set with a standard telegram output. Its repetition rate depends of variable dt(s) that
is set to 15 seconds by default. Table 8 contains the format of the standard data telegram.
The output of the extended data telegram is set with the command
set<SPACE><RS485Number>:TransferMode=2<CR><LF>
Table 9 contains the format of the extended data telegram.