NOVUS RHT-Air - Manual (Page 4)

RHT-Air
NOVUS AUTOMATION 4/8
In order to configure it for the first time, it is necessary to remove the front cover
and connect it to a computer through a mini-B USB cable. The initial
configurations for wireless are described as follows:
PAN ID (Network Identifier) = 22350 (0x574E)
RF Power (Power Level) = 0 dBm
6.1 RHT-Air SCREENS
Indication screen of the values measured in the equipment:
1 st Screen: Main
In order to configure the communication parameters, you should press the
Button
(for about 5 seconds) until it starts to blink, release it and press
it again to expand it. When the expected value appears, release the button
and wait until the screen stops blinking (for about 10 seconds). If you want to
move on to the following screens, press the button
.
Configuration screen of the Modbus Address – Sets the address of the
module on the Modbus network. Between 1 and 246.
2 nd Screen: Modbus address
Time configuration screen – Sets the update interval.
3 rd Screen: Update interval
Mode’s configuration screen – Sets the indication mode.
4 th Screen: Indication mode
Configuration screens of the Unit: It sets which temperature unit should be
used (ºC or ºF).
5 th Screen: Unit
Screens for viewing the values measured in the equipment only:
6th Screen: Temperature
7th Screen: Relative Humidity
8th Screen: Dew point
7 BATTERY LIFE
The battery is estimated to last for over a year. There is a fine line between its
life and how the equipment is used. The lower the sensor’s reading interval, the
shorter it will last, as it may, in the worst case scenario, last for 30 days only.
If you wish to save the battery’s energy, it should be set to the lowest interval
possible between updates. The level of transmission power to communicate
with the AirGate-Modbus of the network has an effect on its life, too. So, the
equipment should be configured to operate under the minimum power and as
close to an AirGate-Modbus of the network as possible.
8 WIRELESS
RHT-Air has an IEEE 802.15.4 wireless connection to connect with
AirGates-Modbus that has its firmware updated to a version more recent
than V1.23. The first RHT-Air configuration must be done through a USB
through Software DigiConfig, as the necessary parameters for
communication with AirGates should be set. After the first time it is
configured and matched with a AirGate-Modbus, RHT-Air will operate as a
Modbus RTU slave. From this moment on, all its resources can be accessed
through the reading of its registers in any Modbus RTU site. The
Programming button
can be used for configurations.
The information necessary for data reading without DigiConfig can be found
in this item. Software DigiConfig should be used in order to ensure the
equipment’s correct configuration. After it is configured, its data can be
accessed by any other software with Modbus RTU communication capacity.
7.1 MODBUS COMMANDS
The following Modbus RTU commands (functions) are implemented: For
further information on each one of these functions and on the Modbus
protocol in general, go to www.modbus.org.
READ HOLDING REGISTERS – 0x03
This function can be used to read a value of one or up to 42 retentive
registers, as per the “Retentive Registers Table”.
WRITE HOLDING REGISTERS – 0x06
This function can be used to write in a retentive register, as per the
“Retentive Registers Table”.
7.2 DESCRIPTION OF SOME REGISTERS
Once the RHT-Air meets an AirGate-Modbus and is matched, this AirGate will
be last published by RHT-Air. Therefore, when the Master of the Modbus
network requires that the RH-Air address be read, the response is sent
immediately and the expiration of this publication can be checked through
register 30, which shows how long it has been since the last publication.
REGISTER 6 – PAN ID
A common identifier for each IEEE 802.15.4 wireless network. All machines
from a common network (AirGates-Modbus and RHTs-Air) must be
configured with the same PAN ID
REGISTER 7 – ENCRYPTION
This register should be used to enable or disable the use of encryption. If it
is enabled, the encryption key should be the same used for all equipment
configured with the same PAN ID.
REGISTER 16 – POWER LEVEL
The power level may be adjusted as needed, according to the variations
presented in the table below: The higher the power set, the higher the reach, but
the higher the consumption. It is suggested that the lowest value possible be
configured, since in the event that RHT-Air is not able to communicate with the
AirGate-Modbus, it will automatically increase the transmission power gradually,
until it is able to communicate with AirGate-Modbus or reach the highest
configurable limit. It may be that this register is configured with a value and, after
some time, this value may be altered to adjust to a communicable power.
CODE POWER LEVEL
0 0 dBm
1 2 dBm
2 4 dBm
3 6 dBm
4 8 dBm
5 10 dBm
6 12 dBm
7 14 dBm