Cateye CC-AT100 manual HOW to USE AS AN Altimeter, Reset, Altimeter Function

Reset

When the S/S button and the Mode button are pressed simultaneously, the following data can be reset, depending on the mode.

For resetting trip distance(D), elapsed time(T), average speed(A) and maximum speed (M):

In other modes than altitude measuring mode, press the two buttons simultaneously; then the data of D, T, A and M returns to zero.

E

For resetting the trip altitude gain:

In the sub mode showing the trip altitude gain and total altitude gain, press the two buttons simultaneously; then the data of the trip altitude gain( ) returns to zero.

For resetting the current altitude correction value:

In the main mode showing the current altitude ( ), press the two buttons simultaneously; then the current altitude correction value will be zero and the data will be reset to the initial value of "International Standard Atmosphere" (ISO 2533).

HOW TO USE AS AN ALTIMETER

Correlation between above sea level and pressure

extract from ISO 2533 (Table 1)

A.S.Level	Pres.	A.S.Level	Pres.
4500 m	577 hPa	600 m	943 hPa
4000 m	616 hPa	500 m	955 hPa
3500 m	658 hPa	400 m	966 hPa
3000 m	701 hPa	300 m	978 hPa
2500 m	749 hPa	200 m	989 hPa
2000 m	795 hPa	100 m 1001 hPa
1500 m	845 hPa	0 m 1013 hPa
1000 m	899 hPa	–100 m 1025 hPa
900 m	910 hPa	–200 m 1038 hPa
800 m	921 hPa	–300 m 1050 hPa
700 m	932 hPa

1. Altimeter Function

This unit, loaded with a pressure sensor, measures the altitude by using atmospheric pressure. It esti- mates the altitude by using the "correlation between altitude and pressure" of ISO 2533, based on the International Standard Atmosphere of ICAO (International Civil Aviation Organization). Generally, a con- ventional pressure sensor is affected by temperature and gives errors; but this unit is temperature-com- pensated every 20 seconds and records 1 meter resolution. Also, with a conventional altimeter, altitude data at the same venue varies from time to time because it is affected by the change of the pressure; however, the CATEYE CC-AT100 is not affected by pressure changes when not cycling. It measures three types of altitude data simultaneously: above sea level (current altitude), trip altitude gain (total of altitude gain from the start to the current point) and total altitude gain (accumulation).

Note: The current altitude data may give an incorrect value temporarily, such as when it is brought from indoor to outdoor, or when the energy-saving function is released. This is just an influence of the tem- perature change and is not a malfunction. It will quickly stabilize and return to normal.

The Correlation Between Altitude and Pressure

The higher the altitude gets, the lower the pressure becomes. At venues of which altitudes are under 500m, the pressure decreases by approx. 12hPa per each 100m (Table 1).

Weather and Barometric Pressure Changes

Changes in weather from a HIGH PRESSURE system (clearer, calmer weather) to a LOW PRESSURE system (over-cast, rain, storming weather) can cause a change in the Altitude reading of 300 feet or more. Thunderstorms or other strong low pressure weather conditions, you

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