GE Vivid S60N, Базовое руководство по обслуживанию

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D
IRECTION
FR091521, R
EVISION
1 V
IVID
S60N/V
IVID
S70N B
ASIC
S
ERVICE
M
ANUAL
7-6 Section 7-2 - Service Safety Considerations
P R E L I M I N A R Y
Section 7-5
Noise Troubleshooting
7-5-1 Purpose of this Section
In this section you will find Noise troubleshooting procedures and hints.
7-5-2 Contents in this Section
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Overview of Types of Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Different Power Outlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Different System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Different Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Disconnect External Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
7-5-3 Introduction
Before you start troubleshooting the noise, you should read the following subsections:
• EMI Limitations on page 2 - 4
• EMI Prevention/Abatement on page 2 - 5
• Overview of Types of Noise - see below
When talking to the customer, try to gather as much information as possible about the conditions when
the noise appear:
Is the noise present...
… all the time?
… after some time of use? (After how long time?)
… at special times of the day (or night)? When?
… at all locations in the hospital, or only in one room/area?
… from time to time, no special pattern of time is observed?
7-5-4 Overview of Types of Noise
There are different types of noise. Use the information next to classify the noise and possible cause.
7-5-4-1 Noise Picked Up from the Air
Electromagnetic Interference (EMI) from radio frequencies, magnetic fields, and transients in the air.
If picked up by a probe cable, the noise will be coherent -“penlight noise” pointing down in the picture -
due to the fact that the noise is received on all channels.
• Is it a problem on one probe only?
Try another probe.
• Is it a problem on one of the probe connectors only?
Move the scanner to another location and verify any changes.