2 suunto wristop computer and interference – SUUNTO Vector HR User Manual
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CHaPTeR 2 HeaRT RaTe MonIToR
2.1 suunTo WRIsToP CoMPuTeR and TRansMITTeR In
a WaTeR enVIRonMenT
suunto Wristop computer is water proof to a depth of 30m/00ft. to maintain the water resistance, it is strongly recommended to have
all service done by authorised suunto service personnel.
Heart rate measurement in a water environment is technically demanding for the following reasons:
• pool water with a high chlorine content and seawater may be very conductive and the electrodes of the transmitter may get short
circuited and ecG (ecG = electrocardiogram) signals cannot be detected by the transmitter unit.
• jumping into the 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 the ecG signal.
• the ecG signal strength varies depending on the individual’s tissue composition and the percentage of people who have problems
with heart rate measurement is considerably higher in a water environment than in other use.
note: the Wristop computer is not a dive instrument, and therefore buttons should not be operated (put to use) while under water.
2.2 suunTo WRIsToP CoMPuTeR and InTeRfeRenCe
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.
electromagnetic interference may cause inaccuracy in receiving heart rate signals. the sum of the “above”, “below” and “in” heart rate
values may be shorter than the total elapsed time. the reason for this inaccuracy is that the electromagnetic interference may prevent
the Wristop computer from receiving signals of the transmitter belt perfectly.