My aim is to measure the leakage current through a patient from different positions while undergoing defibrillation.
We are resistively attenuating the biphasic(bipolar) signal from up to 4000V to a +-10V range for input into the DAQ module yet we require additional safeguarding to protect the DAQ module if the attenuation may fail. We are looking at using an AD210 for galvanic isolation yet think we may need something like a gas discharge tube or a transient voltage suppressor as well.
The following are my questions:
- Is it possible to use a series of bi-directional GDT's or TVS's to shunt the voltage and if so can i ground the excess voltage thought the com terminal?
- My attenuation will be a simple 1000:1 voltage divider network. Will i need a separate network for both the input+ and input- terminal?
Attached is a picture of my proposed circuit.