930473 Rev. B
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E n g l i s h
V . E l e c t r o m a g n e t i c I n t e r f e r e n c e ( E M I )
V. ELECTROMAGNETIC INTERFERENCE (EMI)
A. GENERAL
1. Heed all warnings to reduce the risk of unintended seating system movement.
2. Beware of the danger from hand-held transceivers. Never turn on or use a hand-held
transceiver while power to your seating system is on. Use extra care if you believe
that such a device may be in use near your seating system.
3. Be aware of nearby radio or TV stations, and avoid coming close to them.
4. If unintended movement occurs, turn your seating system off as soon as it is safe to
do so.
B. 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. Others are not, and you may not be able to
avoid them.
3. Powered seating systems may be susceptible to electromagnetic interference (EMI)
emitted from sources such as radio stations, TV stations, amateur radio (HAM) trans-
mitters, two-way radios, and cellular phones.
4. EMI can also be produced by conducted sources or electro-static discharge (ESD).
C. WHAT EFFECT CAN EMI HAVE?
1. EMI can cause your seating system, without warning, to:
•Move by itself.
•Move in unintended directions.
If either of these occurs, it could result in severe injury to you or others.
2. EMI can damage the control system of your seating system. This could create a safety
hazard and lead to costly repairs.
D. SOURCES OF EMI
The sources of EMI fall into two 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
•Lap-top computers with phone or fax
•Other personal communication devices
NOTE–
These devices can transmit signals while they are on, even if not in use. Transceivers: these
include two-way radios used in police cars, ambulances and taxicabs. The antenna is usually
mounted on the outside of the vehicle.
2. 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, TV sets or AM/FM radios, CD or tape players.
E. 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:1 above) A person using one of
these devices can bring high levels of EM energy very close to your seating system without
you knowing it.
Summary of Contents for Quickie Smart Seat
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