Design And Function - WIKA PGW23.100.11 Betriebsanleitung

4. Design and function

4. Design and function
Operating principle
The all welded and robust Bourdon tube measuring system produces a pointer rotation
proportional to the pressure. The process pressure is indicated continuously by the pointer
EN
on the dial. The measuring electronics convert the pointer rotation into an electronic signal,
which is further transmitted via the radio module and the antenna.
The model PGW23.100.11 uses the LoRaWAN
designed for energy-saving operation.
This means that communication with a suitable gateway mainly consists of uplinks
(messages originating from the measuring instrument). An uplink always occurs in regular,
preset cycles (transmission rate). The measuring rate can be defined independently of the
transmission rate. If an alarm limit is exceeded or dropped below during a measuring cycle,
a data transfer is carried out, regardless of the set transmission rate.
After a successful uplink, two time-limited windows can be used for the downlink
(message to the measuring instrument). This enables bidirectional communication and
the receipt of network control commands. If this possibility is not used, the end device can
only receive data after a new uplink.
→ For details see: https://lora-alliance.org/sites/default/files/2018-04/what-is-lorawan.pdf
Typical uplinks:
Measured values
■
Alarm parameters
■
Notifications for fault diagnosis
■
Configuration ID (for the identification of changes in the measuring and sending rate)
■
Typical downlink:
Configuration change (e.g. measuring rate, sending rate, alarm parameter etc.), which
can be recognised by the system.
The LoRaWAN
alarms), if the sending packet has not arrived and sends it again with changed sending
properties (spreading factors) until the receipt is confirmed by the system.
Higher spreading factors lead to an increased range, a longer sending time
and also an increased energy consumption of the radio device.
16
automatically detects, in the case of messages to be confirmed (e.g.
®
, class A radio standard which is
®
WIKA operating instructions, model PGW23.100.11