Faraday cage instructions

And here’s more information to look for before doing anything :grinning: @MotaMan


Ensuring proper ground connections for all electrical devices will shunt high frequency interference to an earth ground or common. If grounding is not done properly, cables, grounds, or electrical equipment can act as a very powerful antenna, radiating out a strong EM field. Grounding the fixture and ballast to a common earth ground will help prevent this from occurring.


The length of wire leads between source and device should be as short as possible. Since this is not always possible in the case of remotely mounted ballasts, twisting cables together will help to cancel out the EM fields generated by long runs of cable. Using cable turns with paired power cables or input leads will generate opposing induced currents, minimizing or removing EMI generated by the runs. You should also avoid large loops or wire bundles, either of which will act as an antenna.

Shielding and Filters

Additional components can be used to block or absorb EMI caused by other equipment. Cable runs should be placed in metal conduits, and fluorescent or HID lights can be housed in luminaires with copper mesh or conductive glass to shield against EMI generated by the cables or lamps. All exposed conductors should be shielded. The conductive material of the shielding will absorb the EM field and prevent radiated or conducted EMI. Additionally, EMI filters or ferrite cores can be placed on ballasts, power conductors, and cabling to reduce conducted EMI across the length of the cable.

Additional Methods

Simple alternatives, such as relocating the susceptible devices (e.g. moving a radio outside of the generated EMI field) are also feasible. Changing or replacing the fixture design, using an alternative ballast, reducing lamp wattage, reducing the inductive or capacitive load (or a ballast’s lamp load), or changing the layout of grounded components are all viable methods for reducing EMI within a system.

Hoping that’s helping you MotaMan :grinning:

~Al :innocent: :v: