930484 Rev.A
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V. EMI (ELECTROMAGNETIC INTERFERENCE)
joystick system,Highback Contour seat, flip back armrests,solid flip-up footplate
and GP24 gel cell batteries.
4. The following specialty import devices have an unknown effect on the immunity
level because they have not been tested on the G-424 with the QTRONIX
controller:
Breath Control
Tri-Switch Head Array
Heavy Duty Switched Joystick
Treadle Switch
Ribbon Switch
Proximity Head Array
Zero Touch Switch
4-Zero Touch Switch
5-Zero Touch Switch
Disc Switch
Proportional Head Control
Proportional Mini-Joystick/Chin Control
Buddy Button
Micro Light
Star Board
Wafer Board
Penta Switch
Plate Switch
Soft Switch
Grasp Switch
Wobble Switch
Individuals with physical limitations requiring the use of a specialty control input
device known not to be immune to 20V/m,or not known,should exercise extra care
around known sources of EMI.
There is no way to know the effect on EMI if you add accessories or modify this chair.
Any change to your chair may increase the risk of EMI.Parts from other suppliers have
unknown EMI properties.
F. REPORT ALL SUSPECTED EMI INCIDENTS
You should promptly report any unintended movement or brake release.Be
sure to indicate whether there was a radio wave source near your chair at the
time. Contact:Sunrise Medical Customer Service Department at (800) 333-4000.
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930484 Rev.A
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
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.
2. Medium-Range Mobile Transceivers:
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,TV sets or
AM/FM radios,CD or tape players.
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.1 above)A person using one of these devices can bring high
levels of EM energy very close to your chair without you knowing it.
E. IMMUNITY LEVEL
1. The level of EM energy 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 configurations tested and found to be immune to at least 20 V/m are:
Quickie G-424 power wheelchair with a left-hand mounted Penny &Giles Pilot
integral controller,Highback contour seat,flip-back armrests, solid flip-up
footplate and Gp24 gel cell batteries.
Quickie G-424 power wheelchair with a right-hand mounted QTRONIX remote
V. EMI (ELECTROMAGNETIC INTERFERENCE)