Kaiterra Square User manual

Kaiterra www.kaiterra.com
Kaiterra Square
Modbus User Manual
MARCH 2022

Kaiterra www.kaiterra.com
1.
Introduction
The Kaiterra Square is a commercial air quality monitor that supports multiple communication methods,
including Modbus.
Modbus is a serial communications protocol. Developed for industrial applications, Modbus is relatively
easy to deploy and maintain. Modbus uses the RS485 or Ethernet as its wiring type. Modbus supports
communication to and from multiple devices connected to the same cable or Ethernet network.
The Kaiterra Square provides Modbus/RTU support via the RS-485 port on the device. Kaiterra Square
can still upload data to the cloud via Wi-Fi or Ethernet when Modbus is used for local communication.
Note: Before setting up Modbus for your Kaiterra Square, please make sure your device is
running the latest firmware and make sure the latest version of Kaiterra Enterprise Configuration
Tool is installed on your computer or smartphone.

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Note: If your Kaiterra Square is not
compatible with the current version of
our Kaiterra Enterprise Configuration
Tool, please contact your Kaiterra rep
for further assistance.
2.
Setting up Modbus on the Kaiterra Square
A. Set up Modbus via RS-485
Make sure your power cable is disconnected, and follow the steps in the Kaiterra Square Installation Guide,
to insert the RS-485 communication cables into the pins and fasten the screws. Pin A is for Cable A in RS-
485, and Pin B is for Cable B in RS-485. Connect the power to turn on the device.
B. Prepare for Configuration
Download the Kaiterra Enterprise Configuration
Tool and install it on your computer or
smartphone.
After the device has been turned on, it will
automatically enter the configuration mode for
15 minutes.

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C. Connect to the device
Open the network settings on your computer or smartphone and look for the Wi-Fi network that starts
with “Kaiterra”. Connect to that network.
On the Kaiterra Enterprise Configuration Tool, you can enter a name for the device (e.g. the location of the
device or the serial number) and a project tag. This will provide easy identification and filtering in the
configuration history page later on to help you quickly connect the device to the Kaiterra dashboard.
Enter the Modbus settings details to the applicable fields on the Configuration Tool following the
instructions below:
Setting Device Address
You can customize your device address in the Kaiterra Enterprise Configuration Tool. The device
address is used to identify the device in the system, so please make sure each device is given a unique
device address.
Customize your device address by entering an address from 1 to 247 in the address field in the
Kaiterra Enterprise Configuration Tool. It is recommended to set your device address onsite during or
right after installation, so that you can keep track of the device installed and the corresponding device
address.
Setting Parity Type
You can configure Parity to be odd, even, or none by selecting from the drop down menu in the
Kaiterra Enterprise Configuration Tool. The default setting for Parity is “even”.
If your Modbus network does not use parity checking, select “none”. Please consult your Modbus
network admin or BMS admin to confirm the parity type of your local network. Please note that all
devices in the same network should be set to the same parity type.

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Setting AQI
You can choose your AQI standard and customize your AQI calculation in the Kaiterra Enterprise
Configuration Tool. AQI stands for Air Quality Index, an index calculated based on the concentration
of a set of air pollutants. The Kaiterra Square offers AQI value in the Modbus communication so that
you can integrate the information into your local system.
Choose the AQI standard from the drop down menu in the Kaiterra Enterprise Configuration Tool, and
select the pollutants used for the AQI calculation. Please note that only the pollutants monitored by
your device can be included in the calculation.
Please consult the facility manager or other responsible personnel if the Modbus address is not clear.
Click configure device and disconnect from the “Kaiterra” network

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3.
Communication Protocol - Modbus RTU
Data type and format:
Data length=8
Stop bit=1
Transmission rate=9600
Check: even
Default Modbus address code is 0x01
Commands
1) Read Input Register (0x04) command 01 04 00 00 00 05 30 09 to read all input register
2) Write single Register (0x06) command 01 06 00 00 00 02 08 0B to set the modbus address to 0x02
3) Read holding Register (0x03) command 01 03 00 00 00 02 C4 0B to read all holding register
Data format
Address
Function
Data
Error check
Data length
1
1
N
16 digit CRC code
(Cyclic Redundancy Check)

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Register Address
Address
Content
R/W Property
Comments
Input register 0
PM2.5
R
0-999 ug/m3
Input register 1
TVOC
R
0-60000 ppb
Input register 2
Temperature
R
-30.0-50.0℃
Input register 3
Humidity
R
0.0%-100% RH
Input register 4
CO2
R
0-9999 ppm
Input register 5
PM10
R
0-999 ug/m3
Input register 6
HCHO
R
0-2000 ppb
Input register 7
CO
R
0.0-500.0 ppm
Input register 8
O3
R
0.0-100.0 ppm
Input register 9
Reserved
R
Input register 10
Reserved
R
Input register 11
Reserved
R
Input register 12
Reserved
R
Input register 13
Reserved
R
Input register 14
AQI
R
0-500

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Holding Register 0
Modbus address code
R/W
Min 1, Max 247
* Other features could be customized upon requests.
* Temperature is in absolute temperature T(k)=273.15+t(celsius)
* Temperature and humidity have resolution of 0.1, the transmitted data is 10 times of the raw data.