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Article no.: 5081200002 2022_10_17 Subject to technical change! Errors excepted.
11
Interfaces and Options
11.1
Optical (infrared) interface
For the communication with the optical interface an optocoupler and the ‘Device Monitor’ is necessary. The
optocoupler and the ‘Device
Monitor’ software are available as accessory equipment.
Baud rate: 2400 baud
11.2
Radio interface wireless M-Bus (optional)
The radio interface is for the transmission of meter data (absolute values).
General information about the radio interface
When installing the radio components, avoid metallic material directly in front of the housing.
The transmission quality (range, telegram processing) of radio components can be negatively influenced by
instruments or equipment with electromagnetic emissions, such as telephones (particularly LTE mobile radio
standard), wi-fi routers, baby monitors, remote control units, electric motors, etc.
In addition, the construction of the building has a strong influence on the transmission range and coverage.
The factory-setting of the internal clock inside the heat cost allocator is standard (winter) Central European
Time (GMT +1). There is no automatic changeover to daylight savings (summer) time.
The radio function is deactivated upon delivery (see 11.2.6 “Activation of the radio interface”)
11.2.1
Technical data radio
Frequency
868 MHz
Transmission power
up to 10 dBm
Protocol
wireless M-Bus based on EN 13757-4
Selectable modes
S1 / T1 / C1
Telegrams
-
short telegram AMR (in conformity to OMS-Spec_Vol2_Primary_v301):
serial number, date/time, current consumption, due date, due date
value, hint flag, time of hint flag
-
long telegram for walk-by read-out:
serial number, date/time, current consumption, due date, due date
value,
15 monthly values, 15 semimonthly values, hint flag, time of hint flag
Encryption
AES: Advanced Encryption Standard; key length: 128 bits
11.2.2
Radio configuration
Parameter
Possible settings
Mode
S1 / 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 (any weekday)
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 (Key-Type)
-
Master Key
-
customer specific key
-
random key per instrument
AES-128-Encryption
-
activated / deactivated
Type of telegram
-
short telegram AMR (OMS-Spec_Vol2_Primary_v301)
-
long telegram for walk-by read-out