Electromagnetic interference (EMI) and radio frequency interference (RFI) from the devices in the
Tetration (Secure Workload) cluster rack can adversely affect other devices such as
radio and television (TV) receivers operating near the rack. Radio frequencies that
emanate from the devices in the rack can also interfere with cordless and low-power
telephones. Conversely, RFI from high-power telephones can cause spurious characters to
appear on the device monitors.
RFI is any EMI with a frequency above 10 kHz. This type of interference can travel from the switch to other devices through
the power cable and power source or through the air as transmitted radio waves. The Federal Communications Commission (FCC)
publishes specific regulations to limit the amount of EMI and RFI that can be emitted by computing equipment. Each switch
meets these FCC regulations.
When wires are run for any significant distance in an electromagnetic field, interference can
occur between the field and the signals on the wires with the following implications:
Bad wiring can result in radio interference emanating from the plant wiring.
Strong EMI, especially when it is caused by lightning or radio transmitters, can
destroy the signal drivers and receivers in the chassis and even create an
electrical hazard by conducting power surges through lines into equipment.
To predict and prevent strong EMI, consult experts in RFI.
The wiring is unlikely
to emit radio interference if you use twisted-pair cable with a good
distribution of grounding conductors. If you exceed the recommended distances,
use a high-quality twisted-pair cable with one ground conductor for each data
signal when applicable.
If the wires exceed the recommended distances, or if wires pass between buildings, give special
consideration to the effect of a lightning strike in your vicinity. The
electromagnetic pulse caused by lightning or other high-energy phenomena can easily
couple enough energy into unshielded conductors to destroy electronic devices.
Consult experts in electrical surge suppression and shielding if you have had
similar problems in the past.