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Article no.: 5081200002 2022_10_17 Subject to technical change! Errors excepted.
11.2.3
OMS 4 mode 7
A special radio variant offers the possibility of radio communication according to OMS 4 Mode 7. The protection
profile for smart metering of the Federal Office for Information Security (BSI/Germany) is taken into account here.
11.2.4
Technical data radio OMS 4 mode 7
Frequency
868 MHz
Transmission power
up to 10 dBm
Protocol
wireless M-Bus based on EN 13757-4
Selectable modes
T1 / C1
Type of telegram
-
short telegram AMR (in conformity to OMS-Spec_Vol2_Primary_v4.11):
serial number, date/time, current consumption, due date, due date
value, hint flag, time of hint flag
Encryption
AES: Advanced Encryption Standard; key length: 128 bit
11.2.5
Radio configuration OMS 4 mode 7
Parameter
Possible settings
Mode
T1 / C1; unidirectional
Transmission period
00:00 - 12:00 pm; any time period in the day
Transmission interval
120 seconds - 240 minutes
Weekdays
Monday – Sunday
Weeks in a month
1 - 4 (4: uninterrupted, incl. a possible 5
th
week)
Months
1 - 12
Radio activation date
annually variable (except 29.02.)
AES-128-Encryption (type of key)
-
random key per instrument
AES-128- Encryption
-
activated / deactivated
Type of telegram
-
short telegram AMR (in conformity to OMS-Spec_Vol2_Primary_v4.11)
11.2.6
Activation of the radio interface
The radio interface
leaves the factory deactivated.
After putting the heat cost allocator on the heat conductor
the radio interface will be activated automatically.
When the radio interface is activated an “R“ is shown permanently left below in the LCD (please see 5.2).
The Engelmann heat cost allocator is equipped with an installation radio mode. After the attachment has
recognized the installation of the heat cost allocator, the device sends a radio telegram for one hour every 36
seconds.
If using the compact mode, for one hour after activation the heat cost allocator transmits in installation mode.
This means that format telegrams and compact telegrams are sent alternately.
12
Hint Flags
The Engelmann heat cost allocator has eight basic reference codes, which can also be used in combination.
Hint codes are information on events that differ from the normal operating mode of the heat cost allocator. The
hint codes may have the character of pure information (no limitation of the measurement and memory function),
as well as indicate one or more serious errors of the measurement and memory function. Depending on the
content and type, the indications appear in the display, in the optical reading and in the transmission via radio in
different representation (see also 12.1.1 and 12.1.2).
