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FOREWORD
FOREWORD

Thank you for purchasing the TOPCON Auto Tracking Total Station, GTS-820A

series. For the best performance of the instruments, please carefully read these

instructions and keep them in a convenient location for future reference.

General Handling Precautions

Before starting work or operation, be sure to check that the instrument is functioning
correctly with normal performance.
Do not submerge the instrument into water.
The instrument can not be submerged underwater.
The instrument is designed based on the International Standard IP54, therefore it is protected from
the normal rainfall.
Setting the instrument on a tripod
When mounting the instrument on a tripod, use a wooden tripod when possible. The vibrations that
may occur when using a metallic tripod can effect the measuring precision.
Installing the tribrach
If the tribrach is installed incorrectly, the measuring precision could be effec ted. Occasion ally check the
adjusting screws on the tr i brach. Make sure th e base fixing lever is lock ed and the base fixing screws
are tightened.
TR-5 or TR-5P tribrach should be used for prism side when the traverse surve ys is performed.
Guarding the instrument against shocks
When transporting the instrument, provi de some protection to m in imize risk of shocks . Heavy shocks
may cause the measurement to be faulty.
Carrying the instrument
Always carry the instrument by its handgrip.
Exposing the instrument to extreme heat.
Do not leave the instrument in extreme heat for longer than necessary. It could adversely affect its
performance.
Sudden changes of temperature
Any sudden change of temperature to the instrument or prism may result in a reduction of measuring
distance range, i.e when taking the instrument out from a heated vehicle. Let instrument acclimate
itself to ambient temperature.
Battery level check
Confirm battery level remaining before operating.
Memory back up
The instrument has a built in battery for memory back up. If the battery power is low, “Back up battery
empty” will display. It is still possible to measure the distance and the angle, but t he measured data
and the parameter setting can be lost. Contac t yo ur d ealer, to replace the battery.
Taking the battery out
It is recommended not to take the battery out during the power is on. All the data stored is possible
gone at that time. So please do your assembling or taki ng the battery out after the power is off.
No responsibility
TOPCON Corporation has no responsibility for loss of data stored in the memory in case unexpected
accidents.