Invacare Scooters 10 Part No. 1090132 Rev F
EMI WARNINGS (CONTINUED)
Powered scooters may be susceptible to electromagnetic interference (EMI),
which is interfering electromagnetic energy (EM) emitted from sources such
as radio stations, TV stations, amateur radio (HAM) transmitters, two way
radios, and cellular phones. The interference (from radio wave sources) can
cause the powered scooter to release its brakes, move by itself, or move in
unintended directions. It can also permanently damage the powered
scooter's control system. The intensity of the interfering EM energy can be
measured in volts per meter (V/m). Each powered scooter can resist EMI up
to a certain intensity. This is called its "immunity level." The higher the
immunity level, the greater the protection. At this time, current technology
is capable of achieving at least a 20 V/m immunity level, which would provide
useful protection from the more common sources of radiated EMI.
There are a number of sources of relatively intense electromagnetic fields in
the everyday environment. Some of these sources are obvious and easy to
avoid. Others are not apparent and exposure is unavoidable. However, we
believe that by following the warnings listed, your risk to EMI will be mini-
mized.
The sources of radiated EMI can be broadly classified into three types:
1) Hand-held Portable transceivers (transmitters-receivers with the
antenna mounted directly on the transmitting unit. Examples include:
citizens band (CB) radios, "walkie talkie," security, fire, and police trans-
ceivers, cellular telephones, and other personal communication devices.
**NOTE: Some cellular telephones and similar devices transmit signals
while they are ON, even when not being used;
2) Medium-range mobile transceivers, such as those used in police cars,
fire trucks, ambulances, and taxis. These usually have the antenna
mounted on the outside of the vehicle; and
3) Long-range transmitters and transceivers, such as commercial
broadcast transmitters (radio and TV broadcast antenna towers) and
amateur (HAM) radios.
NOTE: Other types of hand-held devices, such as cordless phones, laptop computers, AM/FM
radios, TV sets, CD players, cassette players, and small appliances, such as electric shavers and
hair dryers, so far as we know, are not likely to cause EMI problems to your powered scooter.
Powered Scooter Electromagnetic Interference (EMI)
Because EM energy rapidly becomes more intense as one moves closer to
the transmitting antenna (source), the EM fields from hand-held radio wave
sources (transceivers) are of special concern. It is possible to unintentionally
bring high levels of EM energy very close to the powered scooter's control
system while using these devices. This can affect powered scooter move-
ment and braking. Therefore, the warnings listed are recommended to
prevent possible interference with the control system of the powered
scooter.
GENERAL GUIDELINESPROCEDURE 1
GENERAL GUIDELINES