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V
. EMI
(ELECTROMAGNETIC INTERFERENCE)
!
WARNING
Read all warnings to reduce the risk of unintended power
wheelchair movement:
1. Beware of the danger from hand-held transceivers.
NEVER turn on or use a hand-held transceiver while
power to your wheelchair is on. Use extra care if you
believe that such a device may be in use near your
power wheelchair.
2. Be aware of nearby radio or TV stations, and avoid
coming close to them.
3. If unintended movement occurs, turn your power
wheelchair off as soon as it is safe.
!
WARNING
A. WHAT IS EMI?
1. EMI means: electromagnetic (EM) interference (I).
EMI comes from radio wave sources such as radio
transmitters and transceivers. (A "transceiver"
is a device that both sends and receives radio
wave signals).
2. There are a number of sources of intense EMI in your
daily environment. Some of these are obvious and
easy to avoid while others are not, and you may not
be able to avoid them.
3. Powered wheelchairs may be susceptible to
electromagnetic interference (EMI) emitted from
sources such as radio stations, TV stations, amateur
radio (HAM) transmitters, two way radios, and
cellular phones.
4. EMI can also be produced by conducted sources or
electrostatic discharge (ESD).
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!
WARNING
B. WHAT EFFECT CAN EMI HAVE?
1. EMI can cause your power wheelchair, without
warning, to:
• Move by itself
• Move in unintended directions
If any of these occurs, it could result in severe injury
to you or others.
2. EMI can damage the control system of your power
wheelchair. This could create a safety hazard, and
lead to costly repairs.
!
WARNING
C. SOURCES OF EMI
The sources of EMI fall into three broad types:
1. Hand-held transceivers:
The antenna is usually mounted directly on the unit.
These include:
• Citizens band (CB) radios
• "Walkie-talkies"
• Security, fire and police radios
• Cellular phones
• Laptop computers with phone or fax
• Other personal communication devices
2. Medium-range mobile transceivers:
NOTE
- These devices can transmit signals while they are
on, even if they are not in use.
These include two-way radios used in police cars,
fire trucks, ambulances and taxi cabs. The antenna is
usually mounted on the outside of the vehicle.
3. Long-range transceivers:
These include commercial radio and TV broadcast
antenna towers and amateur (HAM) radios.
NOTE
- The following are not likely to cause EMI problems:
lap top computers (without phone or fax), cordless phones,
cell phones, TV sets or AM/FM radios, CD or tape players.
!
WARNING
D. DISTANCE FROM THE SOURCE
EM energy rapidly becomes more intense as you get closer
to the source. For this reason, EMI from hand-held devices
is of special concern. (See C. SOURCES OF EMI above).
A person using one of these devices can bring high levels
of EM energy very close to your power wheelchair without
you knowing it.
!
WARNING
E. IMMUNITY LEVEL
1. The level of EMI is measured in volts per meter (V/m).
Every power wheelchair can resist EMI up to a certain
level. This is called its "immunity level".
2. The higher the immunity level, the less the risk of EMI.
It is believed that a 20 V/m immunity level will protect
the power wheelchair user from the more common
sources of radio waves.
3. The tested configuration that was found to be immune
to at least 20 V/m is: Quickie power wheelchair
with a right-hand mounted remote joystick system,
18" (460 mm) seat width, 18" (460 mm) seat depth,
dual post height adjustable armrests, fixed center
mount legrest with one-piece solid footplate, and
Group 24 gel cell batteries.
4. The following specialty input devices have an
unknown effect on the immunity level because they
have not been tested with the Quickie/Zippie and
remote joystick module system:
Input devices:
• Sip & puff
• Proximity head array
• Proportional head control
• Proportional compact joystick
• Proportional micro joystick
• Chin control
• Heavy duty joystick
• Buddy button
• Micro Light switch
&
!
WARNING
Individuals with physical limitations requiring the use of
a specialty control input device known not to be immune
to 20 V/m, should exercise extra care around known
sources of EMI.
!
WARNING
There is no way to know the effect on EMI if you add
accessories or modify this power wheelchair. Any change
to your wheelchair may increase the risk of EMI. Parts
not specifically tested or parts from other suppliers have
unknown EMI properties.
!
WARNING
F. REPORT ALL SUSPECTED EMI INCIDENTS
You should promptly report any unintended movement of
your power wheelchair. Be sure to indicate whether there
was a radio wave source near your power wheelchair at
the time.
Contact: SUNRISE MEDICAL Customer Service Department
at 1-800-263-3390.
!
WARNING
G. EMI FROM POWER WHEELCHAIR
Electromagnetic field emitted by electronic components
included in this power wheelchair may interfere with other
electronic devices emitting similar field, such as shopping
mall alarm systems.
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