no practical sense to aggregate the data.
Each module has its table of read watermeters, where there are IDs (serial numbers) of meters that should be
read by the module. If there are other watermeters in the reach, their messages are ignored. The module supports
receiving and transmitting of messages either in open mode, or in
encrypted mode
. The module allows forwarding
of original
alarm statuses
(”flags”) from watermeters together with normal readings, or conversion of ”flags” into
the
wacoSystem
alarm messages, that are sent immediately.
Content of INFO-messages is configurable. The messages contain identification and current statuses of module
parameters (uptime, battery voltage, processor temperature..), list of read watermeters, timestamps of reading
periods, and counter values of all watermeters in each reading period (including alarm flags). As
up to 110
readings
can be transmitted within one communication session, one message can contain results from up to 5
measurement intervals even in case of reading maximum number of 20 water meters.
The messages with aggregate data are handed over to the application server with using of NB-IoT service of GSM
provider. The data are transferred in form of standard IP/UDP packets, that are routed to the server of remote
reading application operator through the designated Access Point of GSM provider. Application server receives the
messages and performs their decoding, storing and further processing.
The NB-K868 module supports
bi-directional communication
and it is able to receive through the network
messages of ”SET” type, generated by remote computer.
These messages can be used for setting of module
parameters from the remote server.
1.3
Hardware features and power supplying
The module is enclosed in humidity-proof plastic casing with IP65 degree of protection and can be used in interiors
as well as in exteriors. The casing is designed for mounting on the wall or other construction element (beam,
pipe...). Module can be treated with an additional sealing by high-adhesion silicon filling, that can ensure proof
against inundation by water (IP68 grade). If this treatment is required from the manufacturer, it must be ordered
separately.
The module is power supplied by internal battery with up to 6 years lifetime for measurement frequency of 2
hours and broadcasting interval of 8 hours. One message can contain up to 110 readings. Battery lifetime can be
negatively influenced by shorter broadcasting period, or by storing and operation in sites with the temperatures
exceeding the recommended range.
The module is equipped with a SIM-holder for ”Micro-SIM” (3FF) format of SIM-card (15 x 12 x 0,76 mm). SIM-
holder is placed inside the module on the PCB. The module can be ordered with embedded SIM (eSIM) of chosen
GSM operator.
The module can be controlled and configured either by configuration cable, or wirelessly, by infra-red optical
converter. The module is equipped with the special circular aperture (”peephole”) for magnetic fixing of the optical
converter. The module can be also configured remotely, with using of back channel of bi-directional communication.
External appearance of the NB-K868 module is shown in the figure
Figure 1: View of the NB-K868 module
NB-K868
2