Hitachi Microscope & Magnifier S-4800 Manual De Usuario
1-6
1.1.8 Power Line Noise and Electric Field Noise
Image troubles may be observed when a device as given in Table 1-3 or its power line is
installed nearby or, even if it is distant, it is a heavy duty type. When selecting the installation
site, therefore, whether a source of interference is located nearby or not must be checked.
In case an equipment energized by power of a frequency different from the commercial
frequency employed on the Model S-4800 or the power line for it is located nearby, scan
synchronization with power line frequency will become ineffective. Such a location should be
avoided.
Image troubles may be observed when a device as given in Table 1-3 or its power line is
installed nearby or, even if it is distant, it is a heavy duty type. When selecting the installation
site, therefore, whether a source of interference is located nearby or not must be checked.
In case an equipment energized by power of a frequency different from the commercial
frequency employed on the Model S-4800 or the power line for it is located nearby, scan
synchronization with power line frequency will become ineffective. Such a location should be
avoided.
Table 1-3 External Noise Sources
Classification
Noise
Source
Source
Source Equipment
Electric equipment
with contacts
with contacts
Electric discharge
(spark, arc)
(spark, arc)
Flasher (neon sign, ornamental electric bulb),
relay, electromagnetic contactor, thermostat
(warmer, refrigerator, heating iron), cash
register
relay, electromagnetic contactor, thermostat
(warmer, refrigerator, heating iron), cash
register
Equipment utilizing
commutator motor
commutator motor
Electric discharge
(spark, arc),
sliding contact
(spark, arc),
sliding contact
Electric drill, laboratory engine, motor of
sewing machine, cleaner, food mixer, shaver,
massaging machine
sewing machine, cleaner, food mixer, shaver,
massaging machine
Electric discharge
tube
tube
Glow discharge
Neon discharge tube, high pressure mercury
arc lamp
arc lamp
Small-sized
electric
equipments
electric
equipments
Controller utilizing
semiconductor
semiconductor
Phase control
(transient noise)
(transient noise)
Thyristor dimmer, inverter
Industrial high
frequency equipment
frequency equipment
Electro-magnetic
emission
emission
Industrial high frequency heater, high
frequency electric welder, microwave oven
frequency electric welder, microwave oven
Medical high
frequency equipment
frequency equipment
Electro-magnetic
emission
emission
VHF/UHF fulgurators, electric scalpel
Equipment using
high frequency
high frequency
Equipment utilizing
ultrasonic wave
ultrasonic wave
Electro-magnetic
emission
emission
Flaw detector, depth sounder, fish finder,
ultrasonic cleaner
ultrasonic cleaner
Electric or magnetic
filed,
Ground current
filed,
Ground current
Induction of commercial frequency
(electrostatic induction, electromagnetic
induction, current leaking in ground)
(electrostatic induction, electromagnetic
induction, current leaking in ground)
Power cable
(transmission line)
(transmission line)
Electric discharge
(corona, arc)
(corona, arc)
Corona, poor insulator, poor contact due to
corroded metal (arc discharge)
corroded metal (arc discharge)
Electric discharge
(spark, arc)
(spark, arc)
Trolley wire, internal equipment, rectifier
Power equipment
Electric railroad / train
Magnetic field
Current flow deviation
Electric discharge
Ignition system
Internal
combustion
engine
combustion
engine
Automobile
Other
Dynamo, voltage regulator, wiper, horn,
winker
winker
Electro-magnetic
emission
emission
Broadcasting equipment, radar
Large power
radio frequency
equipment
equipment
Electro-magnetic
emission
emission
Radio transceiver
.