Thank you for your question regarding earthing electrodes for Magnetic Resonance Imaging (MRI) units and their proximity to other earthing electrodes. It is our pleasure to help.
You are correct to be concerned about placing MRI earthing electrodes in close proximity to other electrodes. Close proximity to other earthing electrodes can increase the likelihood that electrical noise will adversely impact the quality of the image taken by the MRI unit.
MRI systems are extremely sensitive and good electrical earthing (grounding) has been shown to improve the image quality. It is quite often required to provide an earthing electrode system for your MRI unit that has an impedance-to-ground (at 50or 60 Hz) of less than 1-ohm. Additionally, there are often requirements that the MRI’s earthing electrode be placed far enough away from other systems so as not to allow stray currents, harmonics, and other transient electrical noise into the system. There are techniques for measuring the earthing electrode for both its impedance-to-earth and its susceptibility to electrical noise, if the earthing electrode system is designed and installed correctly.
Here is a previous blog we posted regarding MRI units that you may find of interest:
Have you calculated the expected impedance-to-ground of your 3.6 meter electrode? Do you have soil resistivity data for Kuwait City? The reason we ask is that your MRI unit is really going to need some excellent grounding (earthing) if it is to function properly and a single 3.6 meter electrode is probably not going to achieve anywhere near a 1-ohm or less impedance-to-ground. We here at E&S Grounding Solutions are of course more than happy to help you with a proper design, but if not us, please get someone with the proper software and expertise to ensure that your MRI unit will function properly.
Please feel free to contact one of our engineers directly and they will gladly discuss your project with you free of charge.
The Engineering Team at E&S Grounding Solutions
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