biosignal acquisition tool-kit for advanced research applications

Electrocardiography (ECG) Sensor User ManualElectrocardiography (ECG)
User Manual

ATTENTION
Please read this datasheet before
using your biosignalsplux sensor

The information contained in this document has been carefully checked and were made every effort
to ensure its quality. PLUX reserves the right to make changes and improvements to this manual andproducts referenced at any time without notice.
The word Bluetooth and its logo are trademarks of Bluetooth SIG Inc. and any use of such marks isunder license. Other trademarks are the property of their respective own.
Please check your systems and sensors after receiving and before using it the first time to confirm if it
contains all the ordered sensors, accessories and other components. Contact our support via e-mail at
support@plux.info if there are any variations from your original order.
For regulatory information, please see the Regulatory Disclaimer at the end of this document.

PLUX – Wireless Biosignals, S.A.
Av. 5 de Outubro, n. 70 – 2.
1050-059 Lisbon, Portugal
plux@plux.info
http://biosignalsplux.com/
v.1.0© 2020 PLUXThis information is provided "as is," and we make no express or implied warranties whatsoever with respect to functionality, operability, use, fitness for aparticular purpose, or infringement of rights. We expressly disclaim any liability whatsoever for any direct, indirect, consequential, incidental or special
damages, including, without limitation, lost revenues, lost profits, losses resulting from business interruption or loss of data, regardless of the form of action orlegal theory under which the liability may be asserted, even if advised of the possibility of such damages.

Electrocardiography (ECG)
User Manual

TABLE OF CONTENTS
1.

General Information ............................................................................................................. 4
1.1. General Description ........................................................................................................... 4
1.2. Typical Unfiltered Sensor Output........................................................................................ 4
1.3. Sensor Specifications ......................................................................................................... 5
1.4. Features ............................................................................................................................ 5
1.5. Applications....................................................................................................................... 5
1.6. Transfer Function (Conversion Formula) ............................................................................. 5
1.7. Electrode Connections & Sleeve Color Meanings................................................................. 6
1.8. Physical Characteristics ...................................................................................................... 6

2. Sensor Application Notes .......................................................................................................... 7
3. Using the Electrocardiography (ECG) Sensor with biosignalsplux & OpenSignals ......................... 8
3.1. Connecting the sensor to biosignalsplux Systems ................................................................ 8
3.1.1. biosignalsplux 4-Channel Hubs ............................................................................................. 8
3.1.2. biosignalsplux 8-Channel Hubs ............................................................................................. 8
3.1.3. biosignalsplux Solo & Single-Channel openBAN Devices ..................................................... 93.2. Configuring the Sensor in OpenSignals (r)evolution............................................................. 9
4. Technical Notes ...................................................................................................................... 124.1. ECG Acquisitions While at Rest ......................................................................................... 124.2. ECG Acquisitions During Physical Activity ......................................................................... 124.3. ECG Acquisitions During Mental Activity ........................................................................... 12
5. Scientific Publications Using the Electrocardiography (ECG) Sensor .......................................... 13
6. Safety & Maintenance ............................................................................................................ 14
6.1. Safety Instructions ........................................................................................................... 14
6.2. Transportation and Storage.............................................................................................. 15
6.3. Cleaning .......................................................................................................................... 15
7. Ordering Guides, Regulatory & Legal Information .................................................................... 16
7.1. Ordering Guide ................................................................................................................ 16
7.2. Guarantee of Quality & Warranty..................................................................................... 16
7.3. Warranty Voidance .......................................................................................................... 16
7.4. Contact & Support ........................................................................................................... 16
7.5. Regulatory Disclaimer ...................................................................................................... 17

3 of 18

Electrocardiography (ECG)
User Manual

1. General Information
1.1. General Description
Our low-noise ECG local differential triode configuration enables fast application and unobtrusive
single-lead ECG data acquisition (although custom electrode cable configurations are available). The
state-of-the-art design of the analog frontend on this sensor is specifically targeted at analyzing
minutiae in the data and provides medical-grade raw sensor data.
This sensor can be used to extract heart rate data and other ECG features, enabling its application in
research fields such as biomedical, biofeedback, psychophysiology, and sports, among many others.
Together with the Heart Rate Variability (HRV) add-on for our OpenSignals (r)evolution software, one
can easily record and extract meaningful temporal, spectral, and nonlinear signal parameters forfurther analysis of the acquired sensor data.

Figure 1: biosignalsplux Electrocardiography (ECG) sensor (standard version).

1.2. Typical Unfiltered Sensor Output
Figure 2 shows a typical unfiltered ECG sensor output acquired while at rest. The raw digital sensor
values received from the biosignalsplux device ranged between 0 and 2n - 1 (n=sampling resolution)
were converted into the original unit of measurement of this sensor (mV) using the transfer function
found in section Transfer Function (Conversion Formula).

Figure 2: Typical unfiltered ECG sensor output (signal acquired while at rest).

4 of 18

Electrocardiography (ECG)
User Manual

1.3. Sensor Specifications> Gain:> Bandwidth:> Input Impedance[Typical]:

1019
0.5-100Hz≥ 100GOhm> Range:> Consumption:> CMRR:±1.47mV (@ VCC = 3V)~0.5mA
100dB

1.4. Features> Bipolar differential measurement> Pre-conditioned analog output> High signal-to-noise ratio> Medical-grade raw data output> Unobtrusive & lightweight sensor> Pre-conditioned analog output> Ready-to-use form factor

1.5. Applications> Life sciences studies> Heart rate & Heart rate variability> Biometrics> Physiology Studies> Biofeedback> Biomedical device prototyping> Human-Computer Interaction> Affective Computing> Psychophysiology

1.6. Transfer Function (Conversion Formula)
The analog sensor signals acquired with biosignalsplux devices are converted into digital values ranged
between 0 and 2n - 1 (n=sampling resolution, usually 8-bit or 16-bit) and streamed in the raw digitalformat.
In most applications, the original physical unit of the acquired ECG signal is preferred or required. The
raw digital sensor samples can be converted back into millivolt (mV) using the following formulas:
𝐴𝐷𝐶 1( 𝑛 − ) × 𝑉𝐶𝐶
2
𝐸𝐶𝐺(𝑉) = 2
𝐺𝐸𝐶𝐺
𝐸𝐶𝐺(𝑚𝑉) = 𝐸𝐶𝐺(𝑉) × 1000

(1)
(2)

Valid sensor range: [-1.47mV, 1.47mV]
with:

𝐸𝐶𝐺(𝑉)
𝐸𝐶𝐺(𝑚𝑉)
𝐴𝐷𝐶
𝑛
𝑉𝐶𝐶
𝐺𝐸𝐶𝐺

ECG signal in Volt (V)ECG signal in milli-Volt (mV)Value samples from the sensor/channel (raw digital value)
Sampling resolution (default: 16-bit resolution (n=16), although 12-bit
and 8-bit may also be found in older versions)Operating voltage (3V when used with biosignalsplux)
Sensor gain (1019)

5 of 18

Electrocardiography (ECG)
User Manual

1.7. Electrode Connections & Sleeve Color Meanings
Sleeve Color
Electrode Cable

Red
+

Black
-

White
reference

See section 2 for more information on where to place the electrodes and to connect electrodes cables
for ECG acquisitions.

1.8. Physical Characteristics> W1 x L1 x H1:
1.5cm x 2.1cm x 0.4cm> W2 x L2 x H2:
1.4cm x 1.7cm x 0.5cm> A1:
105.0±0.5cm> A2:
1.5±0.5cm> A3:
3.0±0.5cm
> D:
0.4cm
> Available sleeve colors:
White, Black, Blue, Green, Red, Yellow, Gray, and Brown
Sensor also available with A2 and A3 with 30cm cable lengths. Custom cable lengths for A1, A2, andA3 are possible. For custom lengths, please contact our operations team via orders@plux.info.

Figure 3: Physical characteristics of the standard Electrocardiography (ECG) sensor.

6 of 18

Electrocardiography (ECG)
User Manual

2. Sensor Application Notes
The biosignalsplux ECG is primarily designed for single-lead ECG acquisitions in the Einthoven
configurations. The Einthoven triangle allows you to acquire 3 different ECG leads which only dependon the positioning of your electrode cables:•••

Lead I:
Lead II:
Lead III:measures from RA (right arm) to LA (left arm)measures from RA to LF (left foot)measures from LA to LF

The illustrations shown in Figure 4 and Figure 5 show the recommended electrode placement for theacquisition of ECG signals in Einthoven configurations depending on the different standard ECG sensors
with difference electrode cable lengths.

Figure 4: Electrode placements for ECG acquisitions inEinthoven configurations using the standard ECG sensor
with electrode cable lenghts of 1.5cm (+ & -) and 3 cm(reference).

Figure 5: Electrode placements for ECG acquisitions inEinthoven configurations using the standard ECG sensor B
with electrode cable lengths of 30cm (+, - & reference).

After placing the ECG electrodes correctly on the body, connect the electrode cables of the ECG sensor
according to one of the following configurations:
Table 1: ECG sensor electrode and electrode placement connection.

Lead I
Lead II
Lead III

Positive Electrode (+)(red sleeve)
LA
LF
LF

Negative Electrode (-)(black sleeve)
RA
RA
LA

Reference Electrode(white sleeve)
LF
LA
RA

It is also possible to use a sensor with only the + and – electrodes (must be custom ordered) without
the use of an additional reference electrodes. Such sensors can lead to an increase in baseline noisedue to the lack of a reference electrode but can be an alternative to the 3-electrode sensor for
7 of 18

Electrocardiography (ECG)
User Manualapplications in which a simplified ECG sensor can be useful (e.g. for the extraction of heart rate dataonly).

3. Using the Electrocardiography (ECG) Sensor with biosignalsplux &OpenSignals
3.1. Connecting the sensor to biosignalsplux Systems
3.1.1. biosignalsplux 4-Channel Hubs
The biosignalsplux ECG sensor is compatible with all 4 analog input channels of the 4-channel
biosignalsplux hub, but incompatible with the reference/ground port. Connect the sensor to an analog
input to use it with this device.

Figure 6: ECG compatible biosignalsplux channels (green checkmarks).

3.1.2. biosignalsplux 8-Channel Hubs
The biosignalsplux ECG sensor is compatible with all 8 analog input channels of the 8-channel
biosignalsplux hub, but incompatible with the reference/ground and digital I/O ports. Connect thesensor to an analog input to use it with this device.

Figure 7: ECG compatible biosignalsplux channels (green checkmarks).

8 of 18

Electrocardiography (ECG)
User Manual

3.1.3. biosignalsplux Solo & Single-Channel openBAN Devices
The biosignalsplux ECG sensor is compatible with the analog input channel of the biosignalsplux Solo
(openBAN) device. Connect the sensor to the analog input channel to use it with this device.

Figure 8: Connect the ECG to the analog input channel of the biosignalsplux Solo (openBAN).

3.2. Configuring the Sensor in OpenSignals (r)evolution
Note
Download OpenSignals (r)evolution here: https://biosignalsplux.com/index.php/software

Open the OpenSignals (r)evolution device manager to access and configure your biosignalsplux
device.

Figure 9: Access the OpenSignals (r)evolution device manager.

9 of 18

Electrocardiography (ECG)
User Manual

Select the device you intend to use for acquisition by clicking on ENABLE button on the device panel in
the OpenSignals device manager. The device is activated for acquisition if the ENABLE button is blue.

Figure 10: Enabling the device for acquisition.

Click on the biosignalsplux logo to access the available settings. Select the channel your sensor isconnected to and select the ECG from the dropdown menu highlighted in the next screenshot.

Figure 11: Set the channel type of the channel you have your ECG sensor connected to, to ECG.

Activate the channel for acquisition by clicking on the circle next to the channel type (must be blue). If
not done before, follow the instruction available in section 2 Sensor Application Notes to learn how toapply the sensors and 3.1 Connecting the sensor to biosignalsplux Systems to learn how to connect
your device to your biosignalsplux device. Click on the record button in the OpenSignals main interface
whenever you’re ready for your acquisition.

10 of 18

Electrocardiography (ECG)
User Manual

Figure 12: Start the acquisition whenever you’re ready.

11 of 18

Electrocardiography (ECG)
User Manual

4. Technical Notes
The biosignalsplux technical notes aim to provide technical in-depth information about the different
applications in which the ECG sensor can be applied. Find below more information about the available
technical notes which you can download from the biosignalsplux website.
Downloadbiosignalsplux Technical Notes - ECG

4.1. ECG Acquisitions While at Rest
The purpose of this technical note is to show a typical acquisition of an electrocardiogram. For thisapplication, an ECG with 6m39s was recorded with a subject in an upright standing position. To assess
the quality of the signal, the Signal-to-Noise (SNR) was calculated.

4.2. ECG Acquisitions During Physical Activity
One of the applications of the ECG sensor is to measure cardiac activity during physical activity. In thisexperiment, the subject performed an intensive exercise on an ergometer during a 10min acquisition.
During the first minute, the subject was in a resting state. After this period, the subject has
progressively increased his effort until he reached the maximum effort between minutes 4 and 5,
resting during the last 2m30s.

4.3. ECG Acquisitions During Mental Activity
The purpose of this technical note is to show how a mental task can influence the heartbeat of a
subject. To that effect, a 5min paced visual serial addition test was performed by a test subject.
In this test, the subject is asked to sum two numbers that are shown on a screen, which is used toassess capacity, rate of information processing, and sustained/divided attention.

12 of 18

Electrocardiography (ECG)
User Manual

5. Scientific Publications Using the Electrocardiography (ECG) Sensor
The following scientific resource elements is only a small selection extracted from the list of available
publications using biosignalsplux. Please visit the following website to access the entire up-to-date list.
biosignalsplux Publications
List of Publications

Publications Short List
C. Gerritsen, J. de Man, J. van der Meij, "Physiological and subjective response to injustice: The Effectsof Unjust Evaluations on Physiological Responses and Subjective Experiences", in Proc. of the
IEE/WIC/ACM Int. Joint Conf. on Web Intelligence (WI) and Intelligent Agent Technologies (IAT), vol. 3,
pp. 179-182, 2013
A. Reiss, I. Indlekofer, P. Schmidt, K. van Laerhoven, "Deep PPG: Large-Scale Heart Rate Estimation with
Convolutional Neural Networks", in Sensors, vol. 19, no. 14:3079, pp. 1-27, 2019
A. Kamenz, V. Bibaeva, A. Bernin, S. Ghose, K. von Luck, F. Vogt, L. Müller, "Classification of
Physiological Data in Affective Exergames", in Proc. of the IEEE Symposium Series on Computational
Intelligence (SSCI), pp. 2076-2081, 2018
G. Ramos, M. Alfaras, H. Gamboa, "Real-Time Approach to HRV Analysis", in Proc. Of the 11th Joint Int.
Conf. On Biomedical Engineering Systems and Technologies (BIOSTEC2018), vol. 4, pp. 208-215, 2018
M. Knierim, J. Dominik, V. Dorner, "Desgining Live Biofeedback for Groups to Support Emotion
Managment in Digital Collaboration", in Lecture Notes in Computer Science, vol. 10243, pp. 479-484,
2017
A. Bernardino, C. Vismara, F. Baptista, F. Carnide, S. Oom, S. Bermudez i Badia, E. Gouveia, H. Gamboa,"A dataset for the automatic assessment of functional senior fitness tests using kinect andphysiological sensors", in Proc. of the 1st Int. Conf. on Technology and Innovation in Sports, Health andWellbeing (TISHW), pp. 1-6, 2016
J. Pagán, J. L. Risco-Martín, J. M. Moya, J. L. Ayala, "Modeling methodology for the accurate and prompt
prediction of symptomatic events in chronic diseases.", in Journal of Biomedical Informatics, vol. 62,
pp. 136-147, 2016
M. Cheetham, C. Cepeda, H. Gamboa, "Automated Detection of Mind Wandering: A Mobile
Application", in Proc. of the 9th Int. Joint Conf. on Biomedical Engineering Systems and Technologies(BIOSTEC), vol. 4: BIOSIGNALS, pp. 198-205, 2016
J. Cusveller, C. Gerritsen, J. de Man, "Evoking and Measuring Arousal in Game Settings", in Proc. of theInt. Conf. on Serious Games, vol. 8395, pp. 165-174, 201413 of 18

Electrocardiography (ECG)
User Manual

6. Safety & Maintenance6.1. Safety Instructions
Please read the following safety instructions before using your biosignalsplux system with the ECG
sensor to prevent any damages or problems with the user, test persons and/or biosignalsplux devices.
Violations of these instructions can lead to inferior signal quality and/or damages to the biosignalsplux
system and user.
!

The user should always keep the device and its accessories dry.

!

The user must turn off the biosignalsplux device and contact Technical Support if the systemor accessories reach uncomfortable temperatures.

!

The user should not use the biosignalsplux device in noisy environments (environments withmicrowaves and other similar equipment). Doing so will lead to noise increase in the acquired
signals and Bluetooth connectivity issues.

!

The user must not use the device near the fire or in potentially explosive atmospheres, such asatmospheres with flammable gas.

!

The user should only use the detection surfaces or other approved accessories purchased fromPLUX or by a PLUX agent.

!

The user should inspect the sensors on a regular basis to ensure that they remain in goodworking order.

!

The user should stop using the biosignalsplux device if experience any kind of discomfort orskin irritation.

!

Do not use the system on persons with allergies to silver.

!

The user should dispose detection surfaces after using the biosignalsplux device. Detection
surfaces are single-user and disposable. Reusable electrodes should be reused by the sameuser. Do not use reusable electrodes on several users.

!

The user must not place the device in the microwave.

!

The user must not insert objects into the holes of the device.

!

The user should not open the biosignalsplux device or its accessories. The repair of the sameshould be only done by properly authorized PLUX personnel.

!

The user should make sure the cables do not obstruct the passage of people.

!

The user should use the sensor cables with extreme caution to avoid risk of strangulation.

!

The user should keep a safe distance between the biosignalsplux device and other devices toensure their proper functioning.

!

The user should only send the device to repair to qualified PLUX personnel.
14 of 18

Electrocardiography (ECG)
User Manual!

The user should not immerse the sensors or the biosignalsplux device, nor clean with liquid orabrasives.

!

The user should handle the biosignalsplux device with caution and not expose the device oraccessories to high accelerations and vibrations.

!

biosignalsplux devices should not be used in patients with implanted electronic devices of any
kind, including pace-makers, electronic infusion pumps, stimulators, defibrillators or similar.

!

Do not apply electrodes over damaged or irritated skin.

!

Do not use your device while charging its internal battery.

6.2. Transportation and Storage
Please follow these recommendations to ensure safe transportation and storage of yourbiosignalsplux equipment and sensors to prevent any damaging of your system.
The biosignalsplux equipment and sensors should be stored in the original box in a dry place whenthose are not being used.
•••

Relative humidity: up to 95% with no condensation
Ambient temperature: 10°C to 30°C
Atmospheric pressure between 500hPa and 1060hPa

Whenever the equipment needs to be transported, it should be placed in the original box, since thiswas designed and tested to ensure the equipment and accessories are securely stored.
Take care while handling the transportation of the system and avoid dropping it, since the device is
not shock-proof and should not be placed under stress or sudden acceleration.

6.3. Cleaning
Please follow these cleaning instructions to prevent any damage of the system or the user because of
conducting cleaning methods that may cause any damage.
•The biosignalsplux and sensors should be visually checked before each use and cleaning
process to ensure that no mechanical damage occurred.

•

The biosignalsplux equipment and sensors (including the cables) should be cleaned with aslightly damp cloth or suitable absorbent paper, ensuring no liquid enters the equipment ofsensors. Do not use detergent or any type of cleaning liquid as these may damage yourequipment and/or sensor.

•

Do not clean or re-use detection surfaces (electrodes). They are only suitable for single use
and should be disposed of after usage except indicated otherwise.

15 of 18

Electrocardiography (ECG)
User Manual

7. Ordering Guides, Regulatory & Legal Information
7.1. Ordering Guide
Please follow the following ordering guide when submitting orders of ECG sensors toorders@plux.info. If no specification is provided, the standard version of the sensor will be delivered.
Electrocardiography (ECG) Sensor
SKU Reference
PLUX CodeUPC
SENSPRO-ECG1
820201203
642554231266
Description
Electrocardiography (ECG) sensor with standard physical characteristics and a random cable sleevecolor
Electrodes & Accessories
For a full list of available and compatible electrodes, please visit the biosignalsplux store.

7.2. Guarantee of Quality & Warranty
biosignalsplux sensors have three months quality guarantee from the date of purchase. PLUX
guarantees that the system, sensors and accessories will be free from material or manufacturing
defects for the mentioned time periods following date of purchase.
If PLUX receives notification of any such defects within the guarantee period, it will repair or substitutewith the same unit/model, any products with proven defects at no cost to the client. During the repair
period PLUX promises to provide a temporary replacement under the same specification. Repairs will
be carried out at PLUX’s premises after the equipment has been received.

7.3. Warranty Voidance
Usage of the device that is not in accordance with the handling instructions indicated in the manual,or use with accessories other than those manufactured by PLUX will invalidate the warranty of yourdevices.
Be careful when connecting your biosignalsplux devices, sensors and/or accessories to any third party
device including the usage of the 3rd party connection components that are available forbiosignalsplux systems as the usage of these components will void the electrical warranty of yourbiosignalsplux device and sensors and, if not indicated otherwise, the warranty of the 3rd party
system you’re connecting to the device. Check the electrical specifications of both systems you wantto connect to prevent any damage of the user(s) or the systems.
In the case of warranty voidance, the same applies that we expressly disclaim any liability whatsoever
for any direct, indirect, consequential, incidental or special damages, including, without limitation, lost
revenues, lost profits, losses resulting from business interruption or loss of data, regardless of the formof action or legal theory under which the liability may be asserted, even if advised of the possibility ofsuch damages.

7.4. Contact & Support
Contact us if you are experiencing any problems that cannot be solved with the information given in
the biosignalsplux documentation.
Please send us an e-mail with precise information about the error occurrence, device configuration,
and, if possible, screenshots of the problem to support@plux.info.
16 of 18

Electrocardiography (ECG)
User Manual

7.5. Regulatory Disclaimer
biosignalsplux products are intended for use in life science education and research applications; they
are not medical devices nor are they intended for medical diagnosis, cure, mitigation, treatment or
prevention of disease. We expressly disclaim any liability whatsoever for any direct, indirect,
consequential, incidental or special damages, including, without limitation, lost revenues, lost profits,losses resulting from business interruption or loss of data, regardless of the form of action or legal
theory under which the liability may be asserted, even if advised of the possibility of such damages.

17 of 18

Electrocardiography (ECG)
User Manual

PLUX Wireless Biosignals S.A.
email: plux@plux.info
web: http://www.plux.info
Headquarters
Zona Industrial das Corredouras, Lt. 14 – 1°
2630-369 Arruda dos Vinhos
Portugaltel.: +351 263 978 572
fax: +351 263 978 902
Lisbon Office
Av. 5 de Outubro, n° 79 – 2°1050-059 Lisboa
Portugaltel.: +351 211 956 542
fax: +351 211 956 546

18 of 18