Hello,
I work in a lab that measures small physiological electrical potentials and the topic of equipment grounding has been of interest to me. At times, mains noise appears at large amplitudes and intermittently which completely swashes out the signals of interest. Also, small DC offsets appear even when our amplifiers and DAQ have high pass filters enabled.
I have attached a physical schematic of how my equipment is internally connected to ground. All pieces of equipment are powered via powerbar which is connected to a single wall socket.
The outputs of each amplifier is connected (via BNC) to a separate channel of the DAQ. Each amplifier's AMP GND is connected (via banana plug) to one another and then connected to a large metal table where the measurements are made.
I am curious if this looks to be noise prone either due to common references or ground loops. Would it be recommended to connect each amplifier's CHASSIS GND to AMP GND (as shown with dotted lines)?
**The resistors (49.9 Ohm & 100 Ohm) are internal to the devices.
Thank you for your time
I work in a lab that measures small physiological electrical potentials and the topic of equipment grounding has been of interest to me. At times, mains noise appears at large amplitudes and intermittently which completely swashes out the signals of interest. Also, small DC offsets appear even when our amplifiers and DAQ have high pass filters enabled.
I have attached a physical schematic of how my equipment is internally connected to ground. All pieces of equipment are powered via powerbar which is connected to a single wall socket.
The outputs of each amplifier is connected (via BNC) to a separate channel of the DAQ. Each amplifier's AMP GND is connected (via banana plug) to one another and then connected to a large metal table where the measurements are made.
I am curious if this looks to be noise prone either due to common references or ground loops. Would it be recommended to connect each amplifier's CHASSIS GND to AMP GND (as shown with dotted lines)?
**The resistors (49.9 Ohm & 100 Ohm) are internal to the devices.
Thank you for your time
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