Working with ECG Amplifier simulation

[Getwonder]

Hello,

I am working on ECG AMPLIFIER SIMULATION MODEL. I have downloaded the kit and working on the given example and is working properly. 

My Questions are,

1- This image shows that only two wires are connected to the simulation model to get the ECG while an ECG Waveform is the combination of at least three wires. See here, while the Right leg is always grounded. But in this example the signal is obtained between Right leg and Right Arm which isnt any Lead Combination. So how this got possible?

2- What is the relation of Offset and Frequency that we add in the labviewinstrument.

3- How could we work on the other ECG signals like the Chest Leads as they are 6 in number while here only only wire is provided for it?

Thanks

[Getwonder]

This is a practical circuit that i have developed and simulated through the Simulator. And is working correctly but the same circuit was simulated using the lvinstrument ECG Signal dont give any result.

I am attaching the file of it.

[Steve.J]

A differential amplifier (ECG amplifier is a type of differential amplifier) only has two leads primary leads (and usually a ground lead).  The difference in potential between the two active amplifier inputs is amplified and the amplifier is designed to be immune to common-mode signals on the two leads (like interference).  When multiple leads are attached to a person (both hands and feet, for instance) only two of the leads are connected to the amplifier inputs at a time (except the ground lead is always attached).  In the Einthoven triangle that you referenced, only two of the three points of the triangle are connected to the ECG amplifier at a time.