Precautions; Interference During Exercise - Polar Electro F11 User Manual

11. PRECAUTIONS

11.1 INTERFERENCE DURING EXERCISE

Electromagnetic Interference
Disturbances may occur near high voltage power lines, traffic
lights, overhead lines of electric railways, electric bus lines or
trams, televisions, car motors, bike computers, some motor driven
exercise equipment, cellular phones, or when you walk through
electric security gates.
Exercise Equipment
Several pieces of exercise equipment with electronic or electrical
components such as LED displays, motors, and electrical brakes
may cause interfering stray signals. To try to tackle these problems,
relocate the wrist unit as follows:
1. Remove the transmitter from your chest and use the exercise
equipment as you would normally.
2. Move the wrist unit around until you find an area in which it
displays no stray reading or does not flash the heart symbol.
Interference is often worst right in front of the display panel of
the equipment, while the left or right side of the display is
relatively free of disturbance.
3. Put the transmitter back on your chest and keep the wrist unit in
this interference-free area as far as it is possible.
4. If the Polar heart rate monitor still does not work with the
exercise equipment, this piece of equipment may be electrically
too noisy for wireless heart rate measurement.
Crosstalk
When in non-coded mode the wrist unit picks up transmitter
signals within 3 feet/1 meter. Simultaneous non-coded signals from
more than one transmitter can cause an incorrect readout.
Using the Polar Heart Rate Monitor in a Water Environment
Your Polar heart rate monitor is water resistant to 100 feet/30 meters.
To maintain the water resistance, do not press the buttons of the
wrist unit under water.
Users measuring their heart rate in water may experience
interference for the following reasons:
• Pool water with a high chlorine content and seawater are very
conductive. The electrodes of a transmitter may short-circuit,
which prevents ECG signals from being detected by the
transmitter.
• Jumping into water or strenuous muscle movement during
competitive swimming may cause water resistance that shifts
the transmitter on the body to a location where it is not possible
to pick up ECG signals.
• The ECG signal strength depends on the individual and also
varies depending on an individual's tissue composition.
The percentage of people who have problems in heart rate
measuring is considerably higher in water than in other use.
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