Components
SEM
Sensor Electronic Module (SEM) – The sensor used for data collection. It can store up to 8 GB worth of data and it can transmit it to the Equivital? suite of software via in-built Bluetooth capability.
Vest
This worn garment holds the SEM. It contains fabric electrodes that make contact with the skin to provide physiological and biomechanical data. It comes in 9 sizes.?
Belt Extender
A belt extender can be used to extend the belt by one size. This adds extra flexibility for different body shapes.
SEM Lead
Allows a single SEM to be charged and configured via a standard USB connection from a Windows laptop or PC. It also enables the SEM to be configured or for data from it to be downloaded.
M Dock
Allows up to six SEMs to be docked. The M Docks can be linked together to form a chain. It is recommended to limit the chain to 2-M Docks and use up to 6 for a single computer (36 SEMs). The M Dock has its own power supply to charge the SEMs that are docked but it also has a USB connection to allow the SEMs to be configured and for data from the SEMs to be downloaded
Additional Accessories
- Bluetooth dongle
- Equivital Bluetooth dongle allows for SEM communication with the laptop running Equivital software.?
- Tape Measure
- Needed for correct fitting of vests
- Spray bottle
- Spraying water on electrodes for immediate monitoring of ECG signal.?
Setup and Fitting
SEM Preparation

- For most studies, begin with plugging the SEM into the MDOC. This will turn it on, check configuration, and download any data still on the device. It will also charge the SEM battery so make sure you have enough time to charge.?
- Alternatively, turn on the device using the power button until it turns green. Or you can use the USB connection and use Equivital Manager software.?
- Note: While 6 MDocs can connect to a single laptop, making 36 SEMS maximum connected simultaneously, only 4 SEMS are processed by Qiosk software at the same time. All other SEMS can be charged but only the 4 in order of plugging in, will be configured and data downloaded.?
- If necessary, use Qiosk to reconfigure the SEMs. We have two configurations that are identical except for Bluetooth.?
- Remove SEM from MDoc, wait for lights to stabilize, and press the button quickly to check the lights to ensure it is functioning correctly.?
- Plug SEM into vest. A click sound will indicate it is fully inserted. But if you don't hear one, check the cutout and the four SEM lights should be clearly visible.?
Vest Fitting
- Size the subject: measure the circumference of the chest, below the pectorals. ?
- Match the size. Experience has indicated that the sizing is quite tight so if it is close, try the larger size first. Most people are broad build.??

- Have the subject try on a vest over clothing (light thin shirt like a t-shirt, no sweaters). There should be a 2-6 cm gap between the edges of the triple clasp. Change sizes or add a belt extender if necessary.
- Dampen electrodes using spray bottle to allow for a quicker accurate reading of the ECG signal. Insert a test SEM (one configured to Bluetooth) into the vest and ask the subject to change into the vest. The vest should be worn in contact with the skin. For those who wear bras, it can go over or under them as long as the electrodes are in contact with the skin.?Make sure to attach all three clasps in the row.
- Researcher should then will then check the fit and data quality using a cell phone with Equivital Mobile loaded or EQPro on a computer. The vest sensors need to be in stable contact with the skin even as the subject is moving so have them wiggle a bit or go through a range of motion. If needed, remove the test SEM and switch to the subject specific SEM.
- Be aware that the subject might find the setup uncomfortable so be prepared to switch sizes or add a belt extender.
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Data Transfer and Clean-Up
- Subject should take off vest but not touch SEM
- Separate SEM from Vest by gently pinching the housing.?
- Send vest to washing
- Note: Right now, we are taking these home to wash. Need to use neutral (mild non-biological) washing liquid and garment bags. Hand or Machine wash at low temperature. Reshape while wet and allow to drip dry
- Plug SEM into MDoc. This will offload the data automatically.?
- Once complete remove SEM and turn it off using the button.?
SEMs in the MDoc when power is disconnected will start capturing data and therefore drain battery. Ensure the SEM is removed from any connection and turned off manually.?
Software
Equivital Qiosk
Equivital Manager
eqView Pro
eqView Mobile
Tips & Troubleshooting
- Lotions, oils, perfumes, deodorant or powder should not be used on the area of the body where the Sensor Belt is being fitted
- The SEM shall not be charged at temperatures below 10°C, as this will significantly reduce the charge retained by the SEM and hence the available operating time. It is recommended to charge the SEM above 20°C.
- The EQ02+ SEM should be re-charged a minimum of once every 6 months
- Connect MDocs to power before turning on the laptop.?There can be problems if the SEMs connect to Windows and try and get power from the PC because the mains power is not connected.
- Once connected to the laptop, do not disconnect?the M Dock(s) unless absolutely necessary. We have experienced intermittent issues with the laptop not registering an M Dock after it has been been disconnected and then reconnected. In this case, removing any SEMs from the M Dock before plugging it back has typically allowed the dock to be registered by the laptop again.
- If the power cable is removed from an M Dock while the SEMs attached to it are powered on, the SEMs will automatically start logging.
- Be sure to power off all the connected SEMs if you plan to disconnect the M Dock for an extended period of time. This ensure that the SEMs will not unintentionally record long data logs while the M Dock is unplugged, as such logs can take a long time to download thereby making the SEMs temporarily unusable.
References
SEM lights
| Icon | LED | Indication |
|---|---|---|
| Power Green |
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| CHARGING GREEN/AMBER |
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| EVENT RED/AMBER |
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| DATA BLUE |
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Bluetooth Dongle Lights
The LED indications on the Equivital? Bluetooth Dongle are as follows:
- Solid Green LED – Power on
- Slow Flashing Blue LED – Device Ready
- Solid Blue LED – Searching for devices
- Fast Flashing Blue LED – Sending or Receiving Data