Emi Prevention/Abatement; Probe Environmental Requirements - GE Venue R1 Service Manual

P R E L I M I N A R Y
D 5771498-100, R
IRECTION
2-2-7

EMI Prevention/Abatement

The following table lists recommendations for preventing EMI:
Table 2-4
Ground the Ultrasound
system.
Be aware of Radio
Frequency sources.
Reinstall all screws, Radio
Frequency gaskets, covers,
cores
Replace broken RF gaskets.
Do not place labels where
RF gaskets touch metal.
Use GE-specified harnesses
and peripherals.
Take care with cellular
phones.
Properly route peripheral
cables.
2-2-8

Probe Environmental Requirements

Table 2-5
Operation
Storage
NOTE: System and electronic probes are designed for storage temperatures of -20
to large temperature variations, the probes should be kept at room temperature for a minimum of 10
hours before use.
6
EVISION
EMI Prevention/ Abatement
EMI Rule
Poor grounding is the most likely reason an ultrasound unit will have noisy images.
Check the grounding of the power cord and power outlet.
• Keep the unit at least 5m (16.4 ft) 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.
• After you finish repairing or updating the Ultrasound system, reinstall 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 an 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 causes 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.
Probe Operation and Storage Temperatures
Electronics
o
10 — 40 C (50 — 104
o
-20 — 50 C (-4 — 122
Chapter 2 - Site Preparations
Details
o
F)
o
F)
V ™ S M
ENUE ERVICE ANUAL
o o
to +50 C. When exposed
2-5