Lufft SHM31 User Manual

Communication over UMB-ASCII 2.0
32 Snow depth sensor SHM 31, V2.1
Command
UMB-ASCII 2.0
Standard
value
Read, write,
command
Name Description
MST C
MeasurementStart
Starts the automatic snow depth
measurement
SS<;>
<SS-Nr>
1 C
Standard-Set,
Telegram Format
Requests the current telegram
(standard format 1)
ATI 60 RW
AutoTransmitInterv
al
Repetition rate of measurements
(calculation of snow depth, prepare
telegram and send if applicable)
ATM 0 RW
AutoTransmitMode
0=polling, 1,2,..=telegram format
number
PST <STX> RW
Protocol: Start
character
PEN <EOT> RW
Protocol: End
character
PCR <CR><LF> RW
Protocol: line feed
character
PDS . RW
Protocol: decimal
mark character
PBS : RW
Protocol: block
delimiter character
PPS ; RW
Protocol: parameter
delimiter character
(also for telegram
values)
CHN<;><ChnNum
>
R
Channel; Channel
Number
Query a UMB channel
Table 7: ASCII parameters for measurements and data transmission
Command
UMB-ASCII 2.0
Standard
value
Read,
Write,
Command
Name Description
ID
1
RW
ID
UMB Device-ID (1-255)
BAU 6 RW Baud rate
Query / set the baud rate for RS485 /
SDI-12 interface
2: 57600
4: 28800
6: 19200
8: 14400
12: 9600
24: 4800
48: 2400
96: 1200
(Baud rate = 115200/n)
A change of the baud rate requires a
reset of the device.
SCF 1 RW ScalingFactor
Change of units, e.g. meter (sf=1) to
foot (sf=3,2808399). After a change of
the scaling factor SCF the parameters
AOF, MSD and the distance value in

Lufft SHM31 Specifications

General

Brand	Lufft
Model	SHM31
Category	Accessories
Language	English