ECG machines have different classification methods:
Classified by machine function
According to the function of the machine, the electrocardiograph can be divided into a graphic tracing ordinary electrocardiograph (analog electrocardiograph) and a graphical tracing and analysis diagnostic electrocardiograph (digital intelligent electrocardiograph).
Classification by recorder
The recorder is the trace element of the electrocardiograph. For the analog electrocardiograph, the recorders used in the early stage were mostly coil-type springs with a coil spring as zero-return torque. After the 1990s, position feedback recorders were used. For digital electrocardiographs, the recorder is a thermal or dot matrix printer.
Classified by power supply
According to the power supply method, it can be divided into DC type, AC type, and AC and DC type electrocardiographs. Among them, both cross and direct use are mostly. The DC-powered type uses rechargeable battery for power supply. The AC power supply adopts an AC-DC conversion circuit, which first converts the alternating current into a direct current, and then stabilizes the high-stability voltage-stabilizing circuit to supply the electrocardiograph.
Classified by the recordable signal derivative once
According to the recordable signal derivative, the electrocardiogram is divided into single-lead and multi-lead(such as three-lead, six-lead, and twelve-lead). The electrocardiographic signal amplification channel of the single-lead ECG machine has only one way, and the ECG waveforms of each lead are to be traced one by one. That is, it does not reflect changes in the conduction ECG at the same time. The multi-lead electrocardiograph has multiple channels of amplification. For example, a six-lead electrocardiograph has six amplifiers, which can reflect the simultaneous changes of the ECG signals of six leads at a certain time.