3B Scientific ECG__EMG Box - Manual (Page 2)

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3. Equipment supplied
1 ECG/EMG box
1 Limb attachment leads, 4-position (right arm, left
arm, left leg, right leg), with push-button contacts,
length 1.50 m
2 Packs (60 in each) of ECG attachment electrodes
F55, Ag/AgCl, with gel pre-applied
1 miniDIN connecting cable, 8-pin, 1 m long
1 Instruction sheet for U11396
4. Technical data
Input resistance: > 10 M
Ω
Output voltage: max. ± 1 V
Blocked frequency: 50 - 60 Hz
5. Operation
Important: When attaching the limb leads (“patient
leads”), try to avoid crossing them over, and ensure
that there are no current-carrying conductors
nearby.
Vigorous movements by the person being tested can
cause artefacts (disturbances) in the recorded curves.
The person should remain lying back in a quiet and
relaxed state.
• To prepare for recording the ECG, attach one
electrode each (4 altogether) to the inner
surfaces of both forearms and on the inner
surfaces of both calves.
• Connect the limb leads to the ECG electrodes,
with the correct colour identifications:
RED for the right forearm (right arm), YELLOW
for the left forearm (left arm), GREEN for the left calf
(left leg), and
BLACK for the right calf (see Fig. 1).
• Using the miniDIN connecting cable, connect the
ECG/EMG box to one of the two analog inputs U
in
A
or U
in
B of the 3B NETlog TM unit, whichever is
preferred.
• Switch on the 3B NETlog TM unit and wait for the
box to be detected automatically ("Probe
Detect").
• Place the ECG/EMG box near the test person.
• By means of the push-button on the box, choose
the required standard lead I, II or III.
• For recording the EMG (electromyogram), attach
four electrodes to the arm of the test person as
shown in Fig. 3:
RED to the inner surface of the lower part of the
left forearm, YELLOW to the inner surface of the
upper part of the left forearm, GREEN and
BLACK to the outer surface of the left forearm.
• Select the EMG mode by pressing the button "I"
for about 2 seconds.
6. Applications
Recording an ECG in a relaxed state with the three
standard EINTHOVEN leads.
Studying the P, Q, R, S, T and U waveforms.
Recording an ECG after light physical activity.
Investigating the effects of different body postures
on the ECG curves.
Investigating the effects of external influences
(excitement, fright) on an ECG.
Determining pulse rate from the ECG curves.
Recording an EMG (electromyogram) produced by
muscle contractions; measuring the electric
potentials for involuntary movements of relaxed
muscular regions.
7. Sample experiments
1. Recording the ECG (electrocardiogram) of a
person
Equipment required:
1 3B NETlog TM unit U11300
1 3B NETlab TM software installation U11310
1 ECG/EMG box U11396
• Prepare the experiment as shown in Fig. 1.
• In 3B NETlab TM , open the application program
(template) for the ECG experiment using the
ECG/EMG box.
• Start the template and record the curve for the
chosen ECG variant (in this case, relaxed-state
ECG with Einthoven standard lead I, see Fig. 2).
• Evaluate the ECG curve in accordance with the
information about basic principles in the
template.
• Determine the pulse rate of the person being
tested.
Important: If the ECG just recorded does not
completely resemble the example provided, this is
not a cause for concern. Every person can show
differences from the norm; even healthy hearts show
such variations. The precise interpretation of an ECG
requires much medical experience. This ECG/EMG
box is not an instrument for diagnoses of that kind.
2. Recording the EMG (electromyogram) of a
person
Equipment required:
1 3B NETlog TM unit U11300
1 3B NETlab TM software installation U11310
1 ECG/EMG box U11396
• Set up the experiment as shown in Fig. 3.