Tesla RaDEC Parts list manual

The manual is also available at
www.tesla.cz
EN
RaDEC household air quality indicator
Technical description and operation manual
v.4 –2022

2/14
Table of contents
1 Introduction.............................................................................................................................................................2
2 Description and use.................................................................................................................................................3
3 Package content ......................................................................................................................................................6
4 Technical parameters ..............................................................................................................................................6
5 Operation manual....................................................................................................................................................7
6 Basic maintenance.................................................................................................................................................13
7 Declaration of conformity .....................................................................................................................................13
8 Service ...................................................................................................................................................................14
9 Warranty................................................................................................................................................................14
10 Document revision ................................................................................................................................................14
OWNERSHIP RIGHTS
This publication or its parts may not be copied, reissued, translated or transferred to electronic form in
any way without the prior written consent of TESLA.
Information contained in this manual only applies to the TERA system components specified on the title
sheet. Other versions and modifications may be created without prior notice to users of the existing
version. TESLA strives to ensure that the information contained in this manual is sufficient and error free.
TESLA assumes no liability for errors, omissions and losses resulting from the use of this information. The
liability of TESLA for errors is limited to amending such errors and providing the below-mentioned advisory
service.
The user should become familiar with the basics of the product. If there are any problems with operating
the product specified on the title sheet, please contact:
TESLA
Rubeška 215/1
190 00 Prague 9 - Vysočany, Czech Republic
www.tesla.cz
1Introduction
This document describes the technical parameters and operation of the RaDEC household air quality
indicator.
It is a product developed and manufactured in the Czech Republic. All rights to this product are reserved
by TESLA. The offer or the delivery of this product or the services associated with the product does not
involve any transfer of the ownership rights.
Prior to using the product, please read this manual and all the operating and safety notices carefully.
Observing operating and safety precautions can prevent damage to the product or accidents and injuries to
the operators. Operating and safety notices in the document are marked as follows:
Caution!: Any text formatted in this way indicates operating and safety notices.
Use the product in the prescribed manner and for the specified areas of use only. When transferring the
product to third parties, pass this document along with it.

3/14
2Description and use
RaDEC is a household air quality indicator. The product measures the following variables:
- Radon concentration Rn, radon volume activity (RVA)
- Equivalent dose power from photon radiation –radiation (X-rays and gamma rays)
- Carbon monoxide concentration CO
- Carbon dioxide concentration CO2
- Relative concentration of volatile organic compounds (VOC)
- Temperature T
- Relative humidity RH
RaDEC is primarily intended for the indication of substances harmful to the human body in indoor air
and for the measurement of additional parameters of this environment. It can warn the user in the event of
elevated levels of harmful substances so that the user can immediately take appropriate measures, such as
ensuring proper ventilation.
RaDEC is equipped with a colour display with touch control and a touch switch (TESLA logo) on the top
of the case.
In addition to the real-time value shown on the display, the product also creates periodic records of all
measured quantities. These records can be displayed in the form of a graph for each measured variable on
the display (max. 100 records).
RaDEC can be powered from the mains or from a built-in battery.
Thanks to the built-in battery, the indicator is portable and can perform measurements even in areas
without power supply for a minimum of 7 days.
Two alarm limits "warning" and "alert" can be set for the measured variables. If exceeded, the product
will initiate visual indication on the display and acoustic indication by an internal siren.
The product also displays the current date and time.
RaDEC can be placed anywhere in the room. It is recommended to place it as far away as possible from
windows or devices that provide ventilation. The back of the indicator should remain unobstructed.
The product comes in two versions:
TYPE
SPECIFICATIONS
RaDEC
Indication of all variables.
RaDEC light
No gamma radiation indication

4/14
Description of the indicated harmful variables for the human organism and their elimination in living
spaces:
The values are indicative only. Each individual reacts differently to different substances, and what
may be harmless to one may cause trouble to another. If you are concerned about your health, we
recommend that you discuss the issue with an expert. If you are unable to reduce the levels of the indicated
variables in your home to the desired values, we recommend discussing the problem with an expert.
These limits are indicative only. You may use the lower "alert" limits, which will not hurt you in any
way. If you seek less indoor ventilation in winter, for example, you can temporarily tolerate exceeding these
alerts. In the factory settings, the limits are set to alert you to exceeding those limits where it is generally
agreed that such levels may be hazardous to health (based on international health and medical
recommendations).
Radon concentration Rn, radon volume activity (RVA) –Radon is a natural, colourless, tasteless
and odourless gas produced by the radioactive decay of radium, thorium and uranium in rocks and released
in varying amounts from the Earth's crust. Radon gas enters the atmosphere from the ground surface or
enters directly into buildings from the subsoil that do not have radon insulation or that have poor quality
insulation (e.g., poorly sealed utility penetrations). Another source of radon in buildings include poor quality
building materials or local water sources. Inadequate ventilation of buildings can lead to radon retention in
the building and excessive radon accumulation inside. Prolonged exposure to high concentrations of radon
can cause lung cancer (radon is the second most common cause of lung cancer).
Excessive levels can be reduced by ventilating the space. Due to the method of measurement
(moving average of the values over 6 hours), the effects of ventilation will be slightly delayed. The reference
value is considered to be 300 Bq/m3(annual average). Under the (Czech) law, publicly used premises
(schools, gyms) and workplaces should not exceed this value on average for the whole year. In households,
we would also recommend not to exceed this value, or try to keep it as low as possible, especially if children
stay in the area for a prolonged time. For more information about radon and how to protect yourself from
it, visit https://www.radonovyprogram.cz/
Ideally, we would recommend having the RVA at home of 200 Bq/m3(at times when persons stay
inside), but in some older buildings this may be challenging without structural modifications.
Equivalent dose power from photon radiation (X-ray and gamma radiation) –X-ray and gamma
radiation is high-energy electromagnetic radiation produced by radioactive and other nuclear decay capable
of ionizing matter (ionizing radiation). When living organisms are overexposed to ionising radiation, they
can be damaged. Short-term exposure to intense ionizing radiation can cause radiation burns or various
stages of acute radiation sickness. Lifetime accumulation of minor damage from ionizing radiation can
induce various types of cancer.
Long-term above-limit values may indicate a nuclear accident or the presence of a source of
ionising radiation in the room (a piece of uranium ore, uranium glass, hazardous building material). The
legal limit for the general population is 1 mSv/year from artificial radiation sources (not including natural
and medical radiation). The natural radiation in Czech geological conditions can range from 0.04 to 0.32
µSv/h. Values greater than 0.5 µSv/h are already suspicious; values greater than 1 µSv/h should not be
present in homes and this should be investigated. The equivalent dose is strongly dependent on the
distance from the radiation source (if you put the source close to the product, it may show high values). In
the event of long-term overexposure, inform the relevant authorities. Further reading on the website
https://www.suro.cz/cz/faq/jake-hodnoty-davkoveho-prikonu-muzeme-v-cr-ocekavat
As the maximum acceptable value at home, we would recommend a value of 0.5 –1.0 µSv/h
(depending on the natural background in your area).
Carbon monoxide concentration CO –Carbon monoxide is a colourless, tasteless and odourless
poisonous gas that does not irritate the senses. In households, it can mainly arise as a product of imperfect
gaseous, petrol or fossil combustion from heat sources.
Levels above 100 ppm are hazardous to health (in case of prolonged exposure) and persons should
not stay in such areas. However, levels at 35 ppm may already cause certain side-effects in some people,
while at values above 50 ppm these side-effects occur in almost everyone (especially headaches in case of
prolonged exposure). At concentrations above 150 ppm, death can occur in case of prolonged exposure.

5/14
Above-limit values must be reduced immediately by ventilating and leaving the area at once. A
malfunctioning heat source that exhibits imperfect combustion must be repaired immediately. Typical
household levels should be in the range of 0–9 ppm. Higher values indicate an active source of CO at home.
Carbon dioxide concentration CO2 –Most carbon dioxide in occupied rooms is generated by the
breathing of people inside the room. The concentration increases with the number of people in the room
and the length of time the room remains unventilated. Increased CO2 concentration can cause fatigue,
tiredness and poor concentration.
Excessive levels can be reduced by ventilating the space. Drops in the value on the indicator should
be apparent within minutes. Atmospheric values range between 300–450 ppm. 650–800 ppm is considered
a poorly ventilated space. The maximum acceptable level for long-term residence is typically 1000 ppm.
Higher levels lead to fatigue, headaches and other health problems.
The appropriate alert limit should be set between 1000–1500 ppm.
Relative concentration of volatile organic compounds (VOC) –This is the sum of various organic
compounds that can be present in the home and can cause respiratory irritation, respiratory problems or
allergies and can affect a person's immunity. Such substances include ethanol, components of cigarette
smoke, perfume droplets, household cleaners, fumes from binders (glues) in furniture, paint, kitchen fumes
from frying, burning wax candles and other sources.
The exact measurement of VOCs is very complex because it depends on many factors, in particular
the presence of specific substances in the air. Therefore, the product applies the principle of relative
indication, which is relative to the clean outdoor environment, indicated by percent. Values approaching
100 % indicate extremely polluted air. The normal value of this indicator in a household should be in the
range of 10–50 %.

6/14
3Package content
RaDEC indicator
Power adapter 230 VAC/5 VDC
USB power cable
Operation manual
4Technical parameters
Product Air quality indicator RaDEC
Type designation 042 127 252 000 RaDEC
042 127 257 000 RaDEC light
Sensitivity for Rn concentration measurement 0.055 imp/hr/Bq/m3,
measured from RaA+RaC
Statistical error of Rn value at 300 Bq/m3 ± 24 % at 1 hour measurement
± 5 % at 24 h measurement
Rn measuring range approx. 30 –60000 Bq/m3
Rn measurement and display interval 6 minutes, (moving average 60x6 min)
Gamma detection sensitivity 0.75 imp/sec/1uSv/hr
Gamma measuring range 0.1 –10000 uSv/hr
Gamma measurement and display interval 3 sec, value smoothed
By weighted averages
CO measuring range 0 –800 ppm
CO measurement and display interval 3 sec
CO measurement accuracy better than ± 20 % / 5 years
O2measuring range 0–40000 ppm
CO2measurement and display interval 1 min,
CO2 measurement accuracy, ± 20 %
VOC measuring range 1–100 %
VOC measurement and display interval 3 sec
Temp. measuring range 40–125 °C
RH measuring range 0–100 %
Temp. and RH measurement and display interval 1 min
RH measurement accuracy ± 5 %
Max. number of records 2570
Recording interval 1 hour
Record value
radon current moving average value
other variables hourly average
Power supply built-in battery or
charger via USB-C port
Battery life min. 7 days
Dimension Ø 130 x 110 mm
Guaranteed operating conditions temperature: 10 to 50 °C
RH: 0 % to 80 %

7/14
5Operation manual
Modes of operation:
The indicator autonomously measures and records the monitored values whenever it is connected
to a power source (to the mains or built-in battery). The product can be operated in two basic modes:
Constant power mode
–The indicator is connected to a 230V socket via mains adapter and USB cable
–Continuous illumination of the display (can be switched off/on, see "Settings")
–Indication and display of all variables
–The built-in battery is charging
Portable mode
–The indicator is not connected to a 230V mains socket via mains adapter and USB cable
–The indicator is powered by the built-in battery
–The display is off (reducing power consumption)
–The display can be switched on for 90 sec by touching the top button (TESLA logo) with
your finger
–The built-in battery discharges gradually, minimum 7 days
Power on and off:
Upon the first start, the indicator can be powered on only by connecting it by mains adapter and USB
cable to a 230V socket. After that, it is recommended to set the current date and time on the product (see
chapter "Settings"). The product then initializes in the first minute of operation. During this phase, the
product may show incorrect values, alarms and readings.
The indicator autonomously measures and records the monitored values whenever it is connected to a
power source (to the mains or built-in battery). The touchscreen display can be switched on by briefly
touching the top button (TESLA logo) with your finger. When the touch screen is switched on, the current
values of the measured value will be displayed.
If the built-in battery is discharged, the product in the portable mode is switched off and can only be
switched on and recharged by connecting it via the mains adapter and USB cable to a 230V socket.
The product can be switched off completely (e.g., for long-term storage) by touching and holding the
top button (TESLA logo) for 5 seconds and confirming the query on the display. The product must be
disconnected from external power/charging during this operation. If the product remains connected to
external power when switching off, the product cannot be switched off. Switching off is accompanied by an
acoustic beep. The product can then be switched on again by connecting it to the mains power supply.
Power supply:
Depending on the application, the product can be powered:
1) From the built-in battery for portable use –The product is equipped with a built-in battery that is
able to ensure autonomous operation of the product for at least 7 days on a single charge. It also
depends on the climatic conditions where the product is operated. The battery is charged via the
USB port using the supplied USB cable. The USB cable can be connected to a PC or to the supplied
power adapter. The battery status indication and charging procedure is described in section "Basic
Maintenance/Charging the Battery".
2) Mains power for stationary use –The product is continuously powered via the USB port to which a
USB mains power adapter is connected using the supplied USB cable. In the event of a mains
failure, the power supply is restored from the built-in battery.

8/14
Control:
Home screen
Fig. 1 –Home screen
At the bottom of the display, there are symbols of all measured substances along with the real-
time value and units. By pressing any of the symbols, the name of the substance and the measured value
will appear in the main display field (radon measurement is selected in the picture). The currently selected
symbol at the bottom is displayed without the measured value. The colours of the individual substance
symbols indicate the current state of the measurement within the set alarm limits. If the value of the
measured substance is “OK”, the symbol is coloured green. An exceeded “warning” limit is visually indicated
by yellow and an exceeded “alert” limit is indicated by red. No alarm limits are indicated for the
"temperature" and "humidity" symbols.
Note: Pressing means touching a specific place on the display with a finger (fingernail) or any pointed object
under certain pressure.
If a flashing yellow warning triangle (Fig. 2) appears in the main field, this is an indication of a
product error, and a list of yellow error states will appear when this triangle is pressed. If this error state
persists for 24 hours (except for low battery voltage, see "Basic Maintenance"), then the product must be
repaired or claimed from the dealer or manufacturer.
Any change in error states is also indicated by an acoustic alarm beep. If the error state persists,
the acoustic alarm beep repeats after 30 minutes.
Fig. 2 –Product error
The three symbols in the upper left corner are “charts”, “configuration” and “information”.
Pressing them takes you to the respective display screen.

9/14
Charts
The screen will show charts generated from the records of the substance that is selected for
display in the main field on the home screen. To change the chart to another substance, you need to go
back to the home screen using the back arrow in the upper field of the display. The chart display shows the
value of the substance indicated in the upper field of the display.
Fig. 3 –Charts
In the upper field of the record, the words “Record x of y” indicates the total number of records
and the record on which the white cursor (x) is located. In the middle below the chart, the record value of
the measured substance is indicated where the white cursor is located.
Individual records of the chart can be navigated using the arrows < and >. The buttons << and >>
can be used to navigate forward and backward by 100 chart records (pages). If there are fewer records,
pressing these buttons does not work.
The chart also shows the currently set “alert” and “warning” alarm limits for the given substance in
yellow and red lines.
The first value in the chart is available after 1 hour from the initial power-on of the product.

10/14
Configuration
The top line is the same for all configuration screens. It contains a back arrow which, when
pressed, switches to the home screen and simultaneously saves the set configuration values, and a line of 5
symbols which represent the individual configuration screens –"alarm limits", "time", "display", "sound"
and "factory settings". The selected icon will always lighten up.
Alarm limits configuration screen
Fig. 4 –Alarm limits configuration screen
Two alarm limits "warning" and "alert" can be set for the measured substances, the exceeding of
which is always indicated visually on the display (in case of the display being off, the display will light up for
5 seconds) and acoustically by a single beep of the internal siren. In the event that any alarm persists for a
long time, the acoustic and visual indication is repeated after 30 minutes. Alarm limits have a hysteresis of
+/- 10 % of the set value for exceeding the limit. An exceeded “warning” limit is visually indicated by yellow
and an exceeded “alert” limit is indicated by red. Acoustic alarms can be switched off in the "Sound
Configuration Screen " settings.
The alarm limits for CO cannot modified by the user due to the high hazardousness of CO and the
importance of the alarm. For the same reason, it is not possible to turn off the acoustic alarm for CO. If the
CO limit is exceeded, the internal siren will beep 5 times with a repeat interval of 3 sec and the display will
light up permanently.
The default limit values, based on international hygiene and medical recommendations, are as follows:
Factory limit settings
warning alert
Rn 300 600 Bq/m3
Gama 1 100 µSv/hr
CO 50 100 ppm
CO21000 2000 ppm
VOC 50 70 %
When setting the limits, the lower line of symbols allows selection of the substance whose limits
are to be set. The factory values of the alarm limits correspond to the above table. By pressing the + and -
buttons or by pressing the alarm value (a numerical pad will pop up) it is possible to change the values. The
factory values of the alarm limits can be restored to factory settings at any time.

11/14
Time configuration screen
When setting time, press to select the value to be set (year, month, day, hour, minute) and then
press + or - to set the current value.
Fig. 5 –Time configuration screen
Display configuration screen
When setting the intensity of the display backlight, use the +and –buttons to select the intensity
in 5 % increments (the default value is around 70 %).
You can also set display light time.
Auto off –the display will only light up for 90 seconds after pressing the top button (TESLA logo) on the
product.
Permanent –the display is always lit when the product is connected to a constant power source –constant
power mode (see chapter "Operation manual –Mode of operation"). In the “portable mode” (see chapter
“Operation manual – Mode of operation”), this button is inactive.
Fig. 6 –Display configuration screen

12/14
Audio and language configuration screen
On this screen, you can press the respective button to select Audio alarm to On/Off. Only the
acoustic alarm for CO cannot be switched off due to the high importance of this alarm. The sounds
associated with pressing the display remain always active.
It is also possible to select the Language –Czech (CZ) / English (ENG). When you select “ENG”, the
menu items will be displayed in English.
The currently set option is indicated by the white colour of the selected button.
Fig. 7 –Sound and language configuration screen
Factory limit settings and CO2 and VOC user calibration screen
Pressing the icon opens the screen where you can choose to restore the factory alarm limit settings
or perform user calibration of CO2 and VOC measurements.
After selecting “Default limits setup?”, a screen will appear where pressing the “Yes” button will
restore the factory alarm limits. This option can be used if it is necessary to restore the limit values set on
the "Alarm limits configuration screen".
After selecting "CO2, VOC meas. calibration", a screen will appear where this calibration can be
initiated. The actual automatic calibration in clean air takes about 5 minutes and the progress is indicated
on the screen. When the calibration is complete, a screen will appear for 5 minutes indicating the successful
completion of the calibration. You can also exit this screen by pressing the back arrow. The calibration
option can be used if the CO2 and VOC sensor needs to be recalibrated (see "Basic Maintenance").
Fig. 8 –Factory setting configuration screen
Information screen ( i )
This screen contains summary information about the status of the product. It serves mainly for
service purposes.

13/14
6Basic maintenance
Charging the battery:
When operating the product in portable mode, the built-in battery must be checked and recharged if
necessary. If the battery is discharged, the product will switch off automatically. The product is switched on
again by connecting the power supply to the USB port.
The current battery charge status is indicated by the battery icon in the top right corner of the display.
The current battery capacity is indicated by the white portion in the battery icon. Low battery is also
indicated by an acoustic alarm and a yellow triangle symbol with an exclamation mark on the display (see
picture below).
Fig. 9 –Incorrect product parameters –low battery
The battery is charged via the USB port using the supplied USB cable. The USB cable can be connected to
a PC or to the supplied power adapter. Plug the USB cable with power supply into the USB port of the
product. The icon will indicate the battery charging status –the battery icon with flash. The battery is fully
charged when the battery icon is completely filled with white colour. The battery is always fully charged
within a maximum of 8 hours after connecting the power adapter.
Current battery capacity
Full battery capacity
Battery is charging
The battery voltage can also be read on the information screen (i). The voltage varies between 3.4 V
(product will be powered off) and about 4.15 V (full charge).
Recalibration of CO2 and VOC sensor
In case of long-term use of the product, the CO2 and VOC sensors may show some deviations and
therefore it is advisable to perform a user calibration of the sensor. User calibration can be started on the
"Factory limit settings and CO2 and VOC user calibration screen". User calibration is based on the
assumption that the product is exposed to the cleanest possible air during automatic calibration, which
corresponds to the outdoor environment. Therefore, it is necessary to place the product outdoors at least
30 min before starting the user calibration and during the calibration. Incorrect calibration, such as inside a
room, will cause subsequent incorrect measurements of CO2 and VOC concentrations.
Faulty product states and product restart
In case of unexpected behaviour of the product (no reaction, etc.), it is possible to restore the product to
the factory settings using the restart button (located on the bottom side of the product behind the small
hole. You will need a needle or other pointed/narrow object to press it).
7Declaration of conformity
Declaration of conformity will be supplied by TESLA on request. To receive the declaration, please use the
contact details at www.tesla.cz.

14/14
8Service
With the exception of "Basic Maintenance", repair and service is only carried out by TESLA.
TESLA
Rubeška 215/1
190 00 Prague 9 - Vysočany, Czech Republic
www.tesla.cz
9Warranty
-This product is supplied with a 24-month warranty starting from the date of purchase.
-If you wish to claim the warranty, please contact the service department.
-The warranty covers defects in material or workmanship, but not damage caused by transport and
handling or improper operation.
-Improper and unprofessional operation of the product (including breaking the seal) will void the
warranty.
-The warranty period is extended by the repair period.
-The product must be disposed of as electronic waste at the end of its useful life.
10 Document revision
Revision
Date
Notes
Rev.1:
31. 01. 2021
First edition
Rev.2:
05. 01. 2022
Second edition
Rev.3:
20. 01. 2022
Extension