GE Vivid E9, Service Manual

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GE H
EALTHCARE
D
IRECTION
GA091568, R
EVISION
5 VIVID E9 S
ERVICE
M
ANUAL
7 - 22 Section 7-10 - Noise troubleshooting
7-10-2 EMI Prevention/abatement
7-10-2-1 Different Power Outlet
Connect the unit to another power outlet and verify if the noise changes or disappear.
NOTE: GE Healthcare requires a dedicated power and ground for the proper operation of its ultrasound
equipment. This dedicated power shall originate at the last distribution panel before the system.
Sites with a mains power system with defined Neutral and Live:
The dedicated line shall consist of one phase, a neutral (not shared with any other circuit), and a full
size ground wire from the distribution panel to the Ultrasound outlet.
Sites with a mains power system without a defined Neutral:
The dedicated line shall consist of one phase (two lines), not shared with any other circuit, and a full
size ground wire from the distribution panel to the Ultrasound outlet.
Please note that image artifacts can occur, if at any time within the facility, the ground from the main
facility's incoming power source to the Ultrasound unit is only a conduit.
7-10-2-2 Different System
Try another VIVID E9 at the same location and look for the same noise. If the noise is present on the
new system too, the noise is most likely from an external source/equipment.
Table 7-2 EMI Prevention/abatement
EMI RULE DETAILS
Be aware of RF sources
• Keep the unit 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.
Ground the unit
• Poor grounding is the most likely reason a unit will have noisy images.
• Check grounding of the power cord and power outlet.
Install all screws, RF
gaskets, covers, cores
• After you finish repairing or updating the system, replace all covers and tighten all screws.
• Any cable with an external connection requires a magnet wrap at each end.
• Install the Card Rack Cover over the Card Rack.
Loose or missing covers or RF gaskets allow radio frequencies to interfere with the ultrasound
signals.
Replace broken RF
gaskets
• If more than 20% or a pair of the fingers on an RF gasket are broken, replace the gasket.
• Do not turn on the unit until any loose metallic part is removed.
Do not place labels where
RF gaskets touch metal Never place a label where RF gaskets meet the unit. otherwise, the gap created will permit RF
leakage. or, if a label has been found in such a position, move the label.
Use GE specified
harnesses and peripherals
• 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.
Take care with cellular
phones
Cellular phones may transmit a 5 V/m signal; that could cause image artifacts.
Properly dress peripheral
cables
• 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.