Hudson Medical Optima Seating System - Manual (Page 6)

SEATING SYSTEM OPERATION SEATING SYSTEM OPERATION SEATING SYSTEM OPERATION SEATING SYSTEM OPERATION
FIGURE 10
FIGURE 9
TILT ONLY CONFIGURATION
SEAT LIFT CONFIGURATION
DOL Limit
Underside of Chair
Magnet
Magnetic Switch
Lift Actuator
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ELECTROMAGNETIC INTERFERENCE ELECTROMAGNETIC INTERFERENCE ELECTROMAGNETIC INTERFERENCE ELECTROMAGNETIC INTERFERENCE
CAUTION:
IT IS VERY IMPORTANT THAT YOU READ THIS INFORMATION REGARDING THE POSSIBLE
EFFECTS OF ELECTROMAGNETIC INTERFERENCE
Powered wheelchairs and motorized scooters (in this text, both will be
referred to as 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. The
interference (from radio wave sources) can cause the powered wheelchair to
release its brakes, move by itself, or move in unintended directions. It can also
permanently damage the powered wheelchair’s control system. The intensity
of the interfering EMI energy can be measured in volts per meter (V/m). Each
powered wheelchair can resist EMI up to a certain intensity. This is called its
“immunity level”. The higher the immunity level, the greater protection.
At this time, current technology is capable of achieving at least a 20V/m
immunity level, which would provide useful protection from the more com-
mon sources of radiated EMI.
There are a number of sources of relatively intense electromagnetic fields in the
everyday environment. Some of these are obvious and easy to avoid. Others
are not apparent and exposure is unavoidable. However, we believe that by
following the warnings listed on page 10 your risk to EMI will be minimized.
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 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.
3. Long-range transmitters and transceivers, such as commercial broad-
cast 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, and cassette players, and small
appliances, such as electric shavers and hair dryers, as far as we know,
are not likely to cause EMI problems to your powered wheelchair.
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