GE LOGIC C2 Series Technical Publication page 71

EMI prevention/abatement
EMI RULE
Be aware of Radio
Frequency sources
Ground the Ultrasound
system
Replace all screws, Radio
Frequency gaskets,
covers, cores
Replace broken Radio
Frequency gaskets
Do not place labels where
Radio Frequency gaskets
touch metal
Use GE specified
harnesses and peripherals
Take care with cellular
phones
Properly route peripheral
cables
Ultrasound System
Direction 5444964-100 English Rev. 5
General Ultrasound system requirements
Prevention/abatement details are provided below:
Table 3-17: EMI prevention/abatement
• Keep the Ultrasound system at least 5 meters (15 feet) away from other
EMI sources.
• Special shielding may be required to eliminate interference problems
caused by high frequency, high powered radio or video broadcast signals.
Poor grounding is the most likely reason an Ultrasound system will have
noisy images. Check grounding of the power cord and power outlet.
• After you finish repairing or updating the Ultrasound system, replace all
covers and tighten all screws.
• Any cable with an external connection requires a magnet wrap at each end.
• Install all covers. Loose or missing covers or Radio Frequency gaskets
allow radio frequencies to interfere with the ultrasound signals.
If more than 20% or a pair of the fingers on a Radio Frequency gasket are
broken, replace the gasket. Do not turn on the Ultrasound system until any
loose metallic part is removed.
Where applicable, never place a label where Radio Frequency gaskets meet
the Ultrasound system. Otherwise, the gap created will permit Radio
Frequency leakage. Or, if a label has been found in such a position, move
the label.
The interconnect cables are grounded and require ferrite beads and other
shielding. Also, cable length, material, and routing are all important; do not
change from what is specified.
Cellular phones may transmit a 5 V/m signal; that could cause image
artifacts.
Where applicable, do not allow cables to lie across the top of the Card Rack
or hang out of the peripheral bays. Loop the excess length for peripheral
cables inside the peripheral bays. Attach the monitor cables to the frame.
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Common Service Information
DETAILS
3-19