Stages cycling Power SPM1 Manual Del Usuario página 7

Zero o set calibration
The zero o set calibration is an important feature of the power meter that
resets the zero o set value for the power meter sensors. There are physical and
environmental conditions that may a ect the zero o set value and there are
methods both manual and automatic that will adjust this value to
accommodate for the changing physical and environmental condition. The
zero o set of the power meter is essentially the sensor reading or values
measured when the power meter has no pedaling load (torque) applied. The
act of calibrating the zero o set causes the power meter to measure the value
at zero load and then records this value as the baseline for power
measurement. Loads applied while pedaling will then be measured as torque
and used by the sensor to determine power in Watts. The zero o set value can
be a ected by the installation of the crank arm and the tightening of the
securing hardware. The torque applied to the securing hardware can impart
some strain into the crank material that is easily accounted for by manually
calibrating the zero o set. Any time the power meter is removed from the bike
and reinstalled the zero o set should be calibrated.
Ambient temperature shifts can also a ect the zero o set to some extent. To
ensure maximum accuracy it is advisable to manually calibrate the zero o set
before each ride. The power meter utilizes automatic temperature sensors to
compensate for temperature changes that take place during the ride. This is
done automatically while you ride and you need not take any further steps to
calibrate the sensor during the ride.
How to calibrate the zero o set
Calibrating the zero o set is a function controlled by the cycle computer or
mobile device (display units) paired to the power meter. Please note that some
device manufacturers refer to the step of resetting the zero o set as
"calibration". When paired to a compatible ANT+ cycle computer or Bluetooth
Smart mobile device, the power meter and display units are in two-way
communication. The display unit can send a command to the power meter to
calibrate the zero o set value and in some cases the resulting zero o set value
will be sent back from the power meter to the display unit and be shown on the
screen. Please note the displayed zero o set value will NOT be zero but rather
a number that corresponds to the measurement taken by the sensor.The
display units will also indicate if the procedure was successful or failed.
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