5.1.2
System failures
As
”
system failure” are considered mainly failures of module’s processor, memory, internal supplying or any other
failures that cause a complete breakdown of the device. If module’s battery voltage is correct, with no signs of
discharging and the device still does not communicate through its configuration port and does not respond to
any commands and this status will not change even after module’s restart (by switching off and switching on its
battery), the system failure probably occur. Perform the replacement of the module according to the instructions
in paragraph
and check functionality of the new module. If the new device works properly, label the original
module as
”
defective” and fill in the appropriate documentation prescribed by internal rules for this case.
5.1.3
Failures of communication with NB-IoT network
Transmitting functionality is signaled by flashing of yellow LED on the module printed circuit board. It can be
seen through the module transparent casing.
If the module is powered by correct voltage, the module communicates through the configuration port, responds
to the configuration commands but the radio-messages from the module are still not received steadily, the possible
reason of the trouble can be a failure of transmitting or receiving of radio signal. The typical indication of trans-
mitting or receiving failures is state of
”
partial” functionality with frequent breakdowns in the receiving data from
the module.
All above described troubles could have on common ground, which is unreliability of radio-communication caused
by one of these reasons:
•
weak radio-signal of NB-IoT network in installation site. RF signal availability can be influenced by weather
conditions (rain, fog..), or by some changes around module installation site as well as around NB-IoT provider
base station.
•
permanent or occasional shading of radio signal caused by construction works or any construction changes
within the premises, or by operation around the installation site (moving of machines, cars, etc.);
•
permanent, periodical or occasional interference (jamming) of radio signal from external source (another radio
system in the same frequency band, or industrial disturbance);
•
low level of transmitting signal caused by transmitter failure;
•
low level of receiving signal caused by receiver failure;
•
low level of transmitting and receiving signal caused by damage of antenna or antenna cable (if external
antenna used).
If above described indications of unreliable radio-communication become evident, proceed with troubleshooting of
the malfunctioning in following steps:
•
visually check surrounding of the installation site to find out if there are any changes that can influence radio
signal (e.g. new objects, things, machines...). If there are such negative circumstances, solve the trouble by
reorganization of the object or by relocation of the module or its antenna (if external antenna used);
•
visually check an external antenna and antenna cable (if used), possibly replace these elements for the spare
ones with proven functionality;
•
check correctness of module settings and perform the check of module overall functionality as described in
paragraph
•
replace the module according to the paragraph
and perform the setting and check of overall functionality
of the new module as described in paragraph
after that;
•
if the module is not properly working even after its replacement for proven device and equipment, the trouble
can be caused by weak signal of NB-IoT network or interference (jamming) from external source in the
installation site. In this case consult actual status of coverage and its future development with your NB-IoT
network provider.
5.1.4
Failures of communication with watermeters
Failures of receiving of radio-messages regularly broadcasted by watermeters generally show themselves as missing
readings from some of read watermeters. In this case proceed with troubleshooting of the malfunctioning in follow-
ing steps:
•
if there are no messages from some watermeter, check its ID (serial number) in the table of read watermeters
(see paragraph
”
Commands for communication with watermeters”);
•
check receiving of watermeter messages in ”RADAR” mode with the length of receiving window at least 45
seconds (see paragraph
”
Commands for communication with watermeters”);
NB-K868
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