Front Panel Ecg Controls - GE 325 Product Manual

SECTION 3
FRONT PANEL ECG CONTROLS
This group of switches, shown in Figure 3-1, controls the direct fetal ECG and
maternal ECG signals.
ECG Rate/CMR Switch
When this switch is in the left position, the simulator outputs an ECG waveform
at the rate selected by the ECG Rate switch. When this switch is in the right
position, the simulator outputs a 60 Hz common mode signal via the ECG Lead
Test connectors.
ECG Rate Switch
This switch controls the QRS repetition rate.
The rate can be fixed at 30, 60, 120, 210, or 240 BPM. The beat-to-beat value is
based on the R-to-R interval on the QRS complex.
The rate can also be set to oscillate centered around the 120 BPM mark; settings
of ALS, A22, and 427 BPM are provided. These settings can be used to test the
maternal/fetal monitor's ECG artifact elimination functionality,
In addition, the rate can be set to produce a ramp signal between 30 and 240
BPM.
Finally the rate can be adjusted manually in conjunction with the Manual
Adjustment knob.
ECG CMR Switch
This switch selects the resistor network used for common mode rejection testing.
Select between balanced and 5 kQ unbalanced.
ECG Mode Switch
This switch selects which ECG mode is simulated in the monitor: FECG or
MECG.
ECG QRS Amplitude Switch
This switch controls the amplitude of the simulated QRS complex. The
selections are: 12, 15, 50, 100, 500, or 2000 pV.
ECG QRS Polarity Switch
This switch sets the simulated R-wave polarity either positive (+) or negative (~).
ECG Lead Test Connectors
These connectors are used for common mode rejection mode testing of the
MECG cable and the monitor's ECG input circuitry. (Refer to Section 4,
Operation for detailed information about this test.)
Controls, indicators, and Connectors * 3-3