ELECTROMAGNETIC INTERFERENCE (EMI)
The rapid development of electronic technology, especially in the area of communications, has saturated
our environment with electromagnetic (EM) radio waves that are emitted by television, radio and
communication signals. These EM wave is invisible and their intensity increases as source increase. All
electrical conductors act as antennas to the EM signals and to varying degrees, all the power wheelchairs
and scooters are susceptible to electromagnetic interference (EMI). The interference could result in
abnormal, unintentional movement and/or erratic control of the vehicle. The United States Food and
drug Administration (FDA) suggests that the following statement be incorporated to the user's manual for
all scooters like S800. Mobility scooters may as susceptible to electromagnetic interference (EMI), which
is interfering electromagnetic energy emitted from sources such as radio stations, TV stations, amateur
radio (HAN) transmitter, two-way radios, cellular phones and alarm systems of shops. The interference
(from radio wave sources) can make the scooter release its brakes, move by itself or move in unintended
directions. It may also permanently damage the scooter's control system. The intensity of the EM energy
can be measured in volts per meter (V/m). Each scooter can resist EMI up to a certain intensity, which is
called interference resistance capacity, and the scooter has an interference resistance capacity of 20 v/m
which would provide useful protection against common sources of radiated EMI.
the warnings listed below can reduce unintended brake release or uncontrolled move that may result in
serious injuries:
1. Do not use portable CB transceiver or communication device like cell phone when the scooter is
started.
2. Be careful and stay away from electromagnetic wave release equipment like radio, TV station, or
etc.
3.
If unintended movement or brake release occurs, turn the powered scooter off as soon as it is safe.
4. Be aware that adding accessories or components, or refitting the scooter may make it more
susceptible to interference from radio wave sources (Note: It is difficult to evaluate the effect on the
overall interference resistance capacity of the mobility scooter).
5. Please report all the incidents of unintended movement or brake release to the manufacturer of the
mobility scooter and note whether there is radio wave source nearby.
