CMi4160
– LoRaWAN
®
Module
10
02/2021
6.6
TRANSMIT INTERVAL
The transmit interval sets how frequently the module transmits data on the
LoRaWAN
®
network. The
parameter can be set to a value between 5 and 1,440 minutes (i.e. between 5-minute and daily
values.)
If Lora Frequency Band L or N (Radio characteristics, Page 24) (0,1% Duty cycle
limitation), is used for transmitting messages (configurated by network server
operator) the minimum transmit interval for DR0, DR1 and DR2 should be set to
minimum 20 min. This will not affect the transmit interval if EcoMode is activated.
The user must always make sure the limits of the local Max. e.r.p and Duty cycle for
the current frequency band is to be followed.
6.6.1
ECOMODE
When EcoMode is active, it is able to achieve a battery-life of at least 11+1 years by utilizing a table
of allowed transmit intervals settings for each data rate. When radio conditions are poor (and data
rate is low), the module will be able to send data less frequently in order to conserve battery-life.
When signal conditions are good, the module will be able to send data more frequently. When EcoMode
is enabled, the module will continuously check if the set transmit interval is “allowed” by the EcoMode
table. If a lower transmit interval is needed for the specific data rate in order to achieve 11 years of
battery life, the module will adjust the parameter accordingly.
Table 3 shows the transmit intervals that the module will use for different data rates in order to achieve
a 11-year battery-life.
Data rate
Transmit interval
DR0
180 min
DR1
120 min
DR2-DR3
60 min
DR4
30 min
DR5
20 min
Table 3: Transmit intervals for different data rates in EcoMode
If EcoMode has been disabled, guarantees about battery-life is no longer valid (even
if EcoMode is activated later).
6.7
MESSAGE FORMATS
CMi4160 has six different message formats:
Standard
,
Compact
,
JSON
,
Scheduled – Daily redundant,
Scheduled – Extended
and
Combined heat/cooling
. Each message type will be described in detail in
this section.
6.7.1
MESSAGE STRUCTURE
Message formats
Standard, Compact, Scheduled – Daily redundant. Scheduled – Extended
and
Combined heat/cooling
are encoded on M-Bus format (date/time field are encoded on M-Bus format
F). Message format JSON is encoded on JSON format.
All messages begin with one byte specifying the message format used.
All M-Bus encoded messages begin with one byte specifying the message format used. Then follows
a sequence of data information blocks (DIBs), each one containing a data information field (DIF), a
value information field (VIF) and a data field (DATA). The structure of the telegram is illustrated in
Figure 4.
