CMi6160
User’s Manual English
CMi6160
User’s Manual English
page | 20 (38)
[2022-10]
v1.4
be carried out at other times but are
planned
at full ours given a set
transmission interval
(T
transmit
). The
figure below illustrates this. The transmissions are planned at time T
1
. The actual
T
transmit
is a random time
between (T
1
+ T
offset
) and (T
1
+ T
offset
+ T
delay
).
T
transmit
, T
offset
and T
delay
are parameters in the product.
Conditions
•
T
offset
+ T
delay
<= T
transmit
o
This should be checked by the device and the OTC App.
•
If T
transmit
is reduced below T
offset
+ T
delay
, then T
offset
should be set to 0 and T
delay
.= T
transmit
.
7.3.4 Data retransmission
If data cannot be sent, due for instance to network issues, there will be a number of retries after which the
device will give up and leave th
e readout as “unsent” in its storage. Next time a transmission is attempted
unsent data will be resent (if possible). Retransmission can be done by FIFO or LIFO.
Rules for retransmissions include maximum age of data, order of data, number of retransmitted data /
transmission interval,
Example 1
A device is configured the following way:
•
Message encoding: M-Bus
•
Auto upload order: FIFO
•
Measurement interval: 60 minutes
•
Transmit interval: 60 minutes
•
Transmit offset: 15 minutes
•
Transmit delay: 30 minutes
•
Maximum uploads per transmission: 4
•
Upload maximum age 72h
A network issue caused the module to be offline for 5 days, while still reading and storing measurement
data. When the device manages to go online the following scenario takes place.
•
The device will start by transmitting measurement data that is 3 days old (FIFO order)
•
The device will send 4 measurement telegrams per hour, at a randomly chosen time between
minute 15 and 45
•
Each telegram contains a single readout, totaling 4 readouts per transmission
•
The device will take approximately 1 day to “catch up” and start sending one measurement per
hour
