User Guide

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7. PRECAUTIONS
7.1 INTERFERENCE DURING EXERCISE
Electromagnetic Interference
Interference may occur near high voltage power lines, traffi c lights,
overhead lines of electric railways, electric bus lines or trams,
televisions, car motors, bike computers, some motor-driven exercise
equipment, cell 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 electric brakes may
cause interference with stray signals. To try to solve the problem,
relocate your 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 fi nd an area where it
displays no stray reading or the heart symbol does not fl ash.
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 from interference.
3. Put the transmitter back on your chest and keep your wrist unit
in this interference-free zone as much as 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
The Polar wrist unit in non-coded mode
of operation picks up
transmitter signals within 3 feet/1 meter. Simultaneous non-coded
signals from more than one transmitter can cause incorrect
readings.
Using Your Polar Heart Rate Monitor in Water
Your Polar heart rate monitor is water resistant and can be used
when swimming. To maintain the water resistance, do not press the
button 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 an ECG signal.
• ECG signal strength is individual and also varies depending
on an individual’s tissue composition. The percentage of
people who have diffi culties with heart rate measurement is
considerably higher in water than in other use.