Kombi-LWEU Economical Multi-Sensor
Instruction Manual
Contents
Introduction
Kombi-LWEU is an economical multi-sensor indoor air quality (IAQ) transmitters developed from the Kube-RHT series. Kombi measures temperature, humidity, total volatile organic compound (TVOC) concentration, differential pressure, carbon dioxide (CO2) concentration, and certain models also particulate matter (PM). It uses the LoRaWAN techology for communication with the cloud.
Before using the 868 MHz radio, make sure it is legal in your country.
Installation
Mounting
Select the installation place so that air can flow freely on all sides of the transmitter and that it represents the air that is to be measured. Avoid heat sources and direct sunlight. Place the device to the measuring location with one of the following ways:
- Mount the wall holder with two universal countersunk screws (ST 2.5 or ST 3.0). Use applicable length depending wall material. In correct orientation, the wall holder has its hooks pointing upwards. Attach Kombi to the holder.
- Place Kombi on any surface with the bottom facing down.
Power supplies
Kombi is powered with a 3.6V Lithium Thionyl battery pack.
The device is supplied with batteries already installed, so it is ready to be used.
Kombi can alternatively be powered with an external supply. When an external power supply is used, the batteries can be omitted or used as a backup supply. Use the micro USB socket to connect an external supply into the device. If the device has a particulate matter sensor (Dust13 and Dust40 models) and the USB cable is longer than 1 m, use a good quality cable with power wires at least 0.2 mm (24 AWG).
Kombi indicates the powerup by blinking the LED next to the micro USB socket.
Settings
Kombi works with its default settings and no parameter configuration is normally required. However, if it is necessary to change the settings of the device, it can be done with Nokeval’s MekuWin software (available for free at www.nokeval.com). Following procedure should be followed in order to get access to the settings:
- Connect a micro USB cable to the connector, and the other end of the cable to a computer.
- If Windows requests for a driver, download it at www.nokeval.com > Support, unzip it to a temporary folder, and show that directory as the location for the driver. If there are problems during the installation, try pushing the button every 5-15 seconds or keeping it pressed so that Kombi will not shut down its USB port.
- Launch the MekuWin program.
- In MekuWin, choose the right COM port from the Ports menu. If the port is not visible, try pushing the button on Kombi to wake up the port.
- From the Port settings menu, choose Protocol = ModbusRTU, Address = 1.
- Click Direct.
- A new window will open for the settings.
The configuration menu includes the following settings: - Protection
o Describes password protection status “None”, “Locked”, “Unlocked”. - Password input/setup
o Unlock protection or change password. See “Protecting the settings” section below for details. - Period
o Time between measurements with options from ranging 5 minutes to 6 hours. Default is 30 min. - LoRaWAN
o If Kombi is used with the Nokeval cloud platform, the default settings are ok. If you wish to manually set the LoRaWAN credentials and/or integrate it with your cloud platform, see “LoRaWAN settings” and “Uplink payload structure” chapters.
Protecting the settings
To protect the settings from being easily adjusted, the configuration menu provides a password box. The password can be formed using up to 16 characters. From the next MekuWin session, the settings can’t be adjusted without knowing the password.
If the displayed status is “Locked”, changes will not be saved to the device. Write the correct password in the “Password input” field and press enter to unlock.
If displayed status is “Unlocked”, the settings and password can be changed and the menu will become locked again after menu is closed.
Note that the password cannot be reset by the user. If the password is forgotten, the password reset can only be made by the manufacturer. Please make sure that the password is remembered if changed.
Operation
After Kombi is successfully installed, it operates on its own. However, there are some considerations that are good to know when using Kombi.
RHT measurement
Temperature is given in °C. Humidity is given in %RH.
TVOC measurement
An auto calibration is necessary for the TVOC sensor. A prolonged exposure to high TVOC concentrations will affect the baseline of the sensor and the sensor will give incorrect readings until the baseline is corrected. The auto calibration can work properly only if Kombi is exposed to fresh air at least some hours after the prolonged exposure. TVOC concentration is given in ppb.
dP measurement
The pressure difference between the outlets is measured using the air flow. The direction of the air flow determines the sign of the reading. If the outlet in the left-hand side is in higher pressure than the outlet in the right-hand side, the reading is positive and vice versa. The pressure difference is given in Pa.
CO2 measurement
An auto calibration is necessary for the sensor. Without it, the sensor will drift over time and eventually give incorrect readings. The auto calibration can work properly only if Kombi is exposed to fresh air at least some hours during each week. In practice, the room must be unoccupied, and its ventilation must be switched on. Concentration is given ppm.
Particulate matter measurement (option)
A small fan sucks air from the opening in the top cover. Inside the device the air passes through a laser beam. The particles will cause a flash when passing the laser, allowing them to be counted and their sizes (diameter) estimated.
The mass of the particles is estimated by assuming that they have a density of 1.65 g/ml and making assumptions of their shape. The result is not accurate if the density, shape, or refractive index deviates significantly from the estimates used in the calibration.
Monitor menu
In MekuWin Mon menu, you can monitor the measurement readings. The sensors are kept continuously on. The values update at the rate the sensor can produce new readings.
Information about LoRaWAN is also displayed to help with potential connection issues.
Cal menu
The calibration menu settings are only for the manufacturer use. They are not explained in this manual.
LoRaWAN settings
Conf menu
Quality
- Unidirectional – uplinks are sent as unconfirmed data with 1 attempt. Acknowledgement is not requested.
- Bidirectional – uplinks are sent as confirmed data. Acknowledgement is requested, and up to 3 attempts are used if acknowledgement is not received.
DevEUI (readonly) – shows the DevEUI of the device. Note that DevEUI can’t be modified.
LoRaWAN credentials
These should be only changed if manually provisioning the device to your own system.
AppKey, AppSKey, NwkSKey: If set, these are displayed as “***” when the menu is re-opened. They can’t be read from the device afterwards.
The keys and EUI:s are written as hex symbols 0-9/A-F, 4 bits per symbol.
- OTAA – Activation mode. If toggled on, Over-the-air-activation is used, else Activation by personalization is used.
- (OTAA mode only) AppEUI – 16 hex symbols
- (OTAA mode only) AppKey – 32 hex symbols
- (ABP mode only) DevAddr – 8 hex symbols
- (ABP mode only) AppSKey – 32 hex symbols
- (ABP mode only) NwkSKey – 32 hex symbols
Other LoRaWAN details
The device always uses Adaptive Data Rate. If it receives no messages from server for 2 subsequent messages, it will lower data rate by 1 step. Then it will lower the data rate by 1 step after every 2 messages until a message is received or data rate 0 is reached. When the device is connected to server, the MAC layer controls the data rate.
Uplink payload structure
This information is only relevant for integrating Kombi with customer’s own cloud platform.
The payload data format consists of a protocol version field and 1 or more messages in length-type-data format. Example payloads are presented at the end of this section for reference.
| Size | Name | Meaning |
| 1B | Protocol version | Version=1 |
| XB | 1 or more messages | Messages in format presented below. |
Message format:
| Size | Name | Meaning |
| 1B | Message length | Bits 0:6 – Message length in bytes, excluding length field and optional age field. Bit 7: If 1, age field is included. |
| (2B) | Optional age field | Age, uint16 * 60 seconds |
| 1B | Message type | Type, e.g. 11 = Flagged utility |
| XB | Message data | Data based on message type |
Message types
Message types:
- 10 Formatted measurement data
- 11 Flagged utility
- 12 Debug
The device may send other message types but those should be ignored. Start of next record can be found based on the length field at start of every message.
Type 10 subtype 1: Measurement data for temperature, humidity etc
Measurement data using bit-flags to describe which measurement fields are included. If the device failed to measure a value, that field will be missing. The format additionally contains status information bitflags field and related to measurements after the measurement data section.
After measurement data, has status bitflags field describing which status fields are included, similarly to the measurement bitflags. Generally if the device failed to produce a measurement, it will have a status code to help identify the issue.
| Size | Name | Value/Meaning |
| 2B | Measurement format | Always 1. |
| 1B | Measurement flags | Tells which of the measurement fields are included. E.g. 0011 1110 = all 6 0010 1110 = All except T & dP |
| 2B | 0 — T | Conversion: int16 / 100 (°C) |
| 2B | 1 — RH | uint16 / 100 (%) |
| 2B | 2 — Reserved | Reserved for future use |
| 2B | 3 — VOC | uintl6 (ppb) |
| 2B | 4 — dP | int16 / 100 (Pa) |
| 2B | 5 — CO2 | uintl6 (ppm) |
| 1B | Status flags | Tells which of the measurement status fields are included. |
| 1B | 0 — T status | 0: Reserved for future use 1+: error number |
| 1B | 1 — RH status | -I I- |
| 1B | 2 — absP status | — -II- |
| 1B | 3 — VOC status | -1 I – |
| 1B | 4 — DP status | -1 I – |
| 1B | 5 — CO2 status | -II- |
Type 10 subtype 10: Measurement data for particulate matter
Measurement data using bit-flags to describe which particulate matter fields are included. If the device failed to measure a value, that field will be missing. The format additionally contains status field.
| Size | Name | Value/Meaning |
| 2B | Measurement format | Always 10. |
| 1B | Measurement flags | Bit flags, describes which fields are included in the message. E.g. 0000 0111 = PM1 + PM2.5 + PM10. |
| 2B | 0 – PM1 | uintl6 / 100 (µg/m3) |
| 2B | 1- PM2.5 | uintl6 / 10 (µg/m3) |
| 2B | 2 – PM10 | uintl6 / 10 (µg/m3) |
| 2B | 3 – PM40 | uintl6 (µg/m3) |
| 2B | 4 – PM4 | uintl6 / 10 (µg/m3) |
| 1B | PM status | 0: Particulate matter sensor OK 1+: error number |
Type 11: Utility
Contains utility information about the device. Uses bit flags to describe which fields are included in the message, similar to message type 10.
| Size | Name | Meaning |
| 1B | Bit flags | If Ox00: Request to send utility. Otherwise describes which fields are included in the message. E.g. 0100 0001 = device type + serial number |
| 3B | 0 — Device type | <0-16777215>, the product number of the device. |
| 2B | 1— Firmware ver | <major 0-255> <minor 0-255> |
| 3B | 2 — Firmware build | <0-16777215> Build number to identify FW version more precisely. |
| 3B | 3 — Firmware ID | <0-16777215> Firmware identifier, for use with firmware update. |
| 1B | 4 — Battery info | <number 0-255>, highest bit describes whether the device has auxiliary power. Other bits: 0-100 = main battery empty/full (1% resolution), 101-121 = reserve battery empty/full (5% resolution), 126 = battery can’t be measured, 127 = no battery attached |
| 2B | 5 — Calibration date | <0-65535> as days after 1.1.2000; 65535 means unknown |
| XB | 6 — Serial number | <symbol> 11-201, 32-126: Ascii-symbols, 128-227: 2 numbers encoded: “00”, “01”, “02”… “99” |
Type 12: Debug information
Debug information message. These should be skipped when reading.
Example uplinks
Here are some example uplinks to help clarify how the uplink payloads are structured.
Bytes are presented as hex values, numbers are LSBF. E.g. consecutive bytes 0x01 and 0x23 converted to unsigned int16 equals 0x01 + 0x23*0x100.
Example – normal measurement data
Bytes (hex): 01 0E 0A 01 00 3B 98 09 B0 0B AD 0D E3 FB 78 05 00
Interpretation:
| Bytes (hex) 01 |
Name | Meaning 01 — Version |
| Protocol version | ||
| OE | Message length | Message length 14, excluding length field. |
| OA | Message type | Type 10 = measurement data |
| 100 | Measurement format | Always 1 |
| 3B | Measurement flags | Which of the measurement fields are included. Ox3B = 0011 1011, meaning all except 2 |
| 9809 | 0 — Temperature | 2456 -> 24.56C |
| BOOB | 1— Relative humidity | 2992 -> 29.92% |
| AD OD | 3 — VOC | 3501 ppb |
| E3 FB | 4 — Differential pressure | -1053 -> -10.53 Pa |
| 7805 | 5 — CO2 | 1400 ppm |
| 0 | Status flags | 00 = No errors |
Example – measurement data with active status
Bytes (hex): 01 0C 0A 01 00 03 98 09 B0 0B 38 01 04 02
Interpretation:
| Bytes (hex) 01 | Name | Meaning 01— Version |
| Protocol version | ||
| OC | Message length | Message length 12, excluding length field. |
| OA | Message type | Type 10 = measurement data |
| 100 | Measurement format | Always 1 |
| 3 | Measurement flags | Which of the measurement fields are included. 03 = 0000 0011, meaning temperature and relative humidity values |
| 9809 | 0 — Temperature | 2456 -> 24.56C |
| BO OB | 1— Relative humidity | 2992 -> 29.92% |
| 38 | Status flags | Which status field are included. 0011 1000 = 3, 4, 5 |
| 1 | 3 — VOC status | VOC measurement status 1 |
| 4 | 4 — DP status | DP measurement status 4 |
| 2 | 5 — CO2 | CO2 measurement status 2 |
Maintenance
Checking the status
Press the button to check the status of Kombi. The LED located next to the micro USB socket will indicate the status:
- If the LED blinks green, everything is fine, and the remaining battery capacity is estimated to be over 20%.
- If the LED blinks red, the remaining battery capacity is estimated to be below 20%.
- If the LED doesn’t blink at all, device isn’t working properly.
Replacing the batteries
- Kombi is powered with a 3.6V Lithium Thionyl battery pack. The batteries should not be replaced by the users.
Cleaning
If there is visible dust inside the device, blow it away with pressurized air while avoiding too strong pressure. The enclosure exterior can be wiped with a damp cloth, but no drop of liquid must enter the device.
Specifications
Environment
Storage temperature
Operating temperature
Protection class
Enclosure material
Measurements
Weight
Dimensions
-40…+80°C, without batteries, non-condensing
-30…+60°C, non-condensing
IP20
ABS+PC, white painted
Kombi-LWEU-RHT-CO2-TVOC-DP 180g with batteries 105 x 75 x 48 mm (-Dust40 model 105 x 75 x 88 mm) 
Power supply
| Batteries | 3.6V Lithium Thionyl battery pack (3 x AA size) |
| Typical battery life | 5 years with 30 minutes transmission interval |
| External | Micro USB type B, 5 ± 0.5 V, max 200 mA, no suspend function |
Measuring and data transmission
| Interval | Configurable: 5min / 10min / 15min /20min / 30min / 1h / 2h / 3h / 4h / 6h |
| Radio | LoRa radio technology with Murata ABZ-093 LoRaWAN modem. |
| Antenna | Internal |
| Frequency band | 863-870 MHz (LoRaWAN 1.0.2 EU band) |
| Transmission power | Max +14 dBm E.R.P. |
Temperature measurement
| Sensor | High-accuracy semiconductor sensor, Swiss |
| Measurement range | -40…+125°C |
| Accuracy | Typically ±0.1°C (+20…+60 °C) |
Humidity measurement
| Sensor | High-accuracy semiconductor sensor, Swiss |
| Measurement range | 0…100 %RH |
| Accuracy | Typically ±2 %RH (+0…+80°C, 0…100 %RH) |
Carbon dioxide concentration
| Sensor | NDIR sensor |
| Measurement range | 400…5000 ppm |
| Accuracy | Typically ±45 ppm + 3% rdg |
| Autocalibration | Must see fresh air (unoccupied room) once a week |
Total volatile organic compound concentration
| Sensor | Semiconductor sensor, Swiss |
| Measurement range | 0.3…30 ppm |
| Accuracy | Typically ±15% |
Differential pressure measurement
| Sensor | High-accuracy flow sensor, Swiss |
| Measurement range | -125…+125 Pa |
| Accuracy | Typically ±0.08 Pa + 3% rdg |
Particulate matter measurement model -Dust13
| Measurement range | 0…1.2 million particles per litre (up to 10,000 particles per second) |
| Particle sizes | 0.4…12.4 µm |
| Particle type | For max accuracy, assumed to be spherical, density 1.65 g/ml, refractive index 1.5 |
| Values measured | PM1, PM2.5, PM4, PM10 |
| PM10 range | 0.01…1 500 000 µg/m3 |
Particulate matter measurement model -Dust40
| Measurement range | 0…2.8 million particles per litre (up to 10,000 particles per second) |
| Particle sizes | 0.4…40 µm |
| Particle type | For max accuracy, assumed to be spherical, density 1.65 g/ml, refractive index 1.5 |
| Values measured | PM1, PM2.5, PM4, PM10, non-standard “PM40” |
| PM10 range | 0.01…1 500 000 µg/m3 |
Warnings
The device must not be disposed in household waste. Observe local regulations concerning the disposal of electrical waste. The device may contain a battery.
Manufacturer
Nokeval Oy
Rounionkatu 107
FI-37150 Nokia
Phone +358 3 342 4810 (Mon-Fri 8:30-16:00 EET)
WWW https://www.nokeval.com/
Email [email protected]
Declaration of conformity
Object of declaration: Wireless measuring device
Model/Type: Kombi-LoRaWAN
Description: Wireless 868MHz temperature, humidity, CO2, differential pressure, TVOC
LoRaWAN-transmitter based on LoRa-modulation.
Manufacturer: Nokeval Oy
Rounionkatu 107, 37150 Nokia, Finland
www.nokeval.com
tel. +358 33424 800
[email protected]
This declaration of conformity is issued under the sole responsibility of the manufacturer.
The object of the declaration described above is in conformity with the relevant Union harmonization legislation:
Directive (RED) 2014/53/EU
Directive (RoHS) 2011/65/EU
| The conformity is given based on the following harmonized standards: | ||
| RED: | EN 300 220-2 V3.1.1 | (2017-02) |
| EN 301 489-1 V2.1.1 | (2017-02) | |
| EN 301 489-3 V2.1.1 | (2017-03) | |
| EMC: | EN 61326-1:2013 | |
| LVD: | EN 61010-1:2010 | |
| RoHS: | EN 50581:2012 | |
Product is marked with CE mark to indicate compliance. Product is designed and manufactured in Finland.
Signed for and on behalf of Nokeval Oy: At Nokia 04.03.2020