Topcon 1004089-01, Tuning Manual

Page: 39 / 58

Chapter 3
– Tuning Preparation
25
3.5.6. Mounting bias calibration
Mounting bias refers to the offset from horizontal at which the GPS
receiver is mounted on the roof of the vehicle. The following things
can affect and change the mounting bias:

Tire pressure

Track tension

Dual tires

Tire sizing

Cabin suspension

Cabin repairs (suspension and mounts)

Removing and refitting the receiver

Mounting location has moved
Note
: Mounting bias calibration should be performed if any of the
above change or at a minimum once every 6-12 months.
Note
: It is advisable to still perform a mounting bias calibration when
using Autonomous as the Correction Source ( System / GPS /
Correction ), even though the console reports that it is not required.
Mounting bias calibration is performed in a clear, flat area well away
from obstacles. If the mounting of the receiver is not quite level, this
calibration will adjust for the actual position.
WARNING: Ensure the vehicle has sufficient space to
travel in a straight line for at least 70 m/230 ft and then
turn at each end of the wayline.
1. From the calibration screen, select the mounting bias calibration
option:

X30: MOUNTING BIAS

Universal terminal:
Note
: To calibrate for mounting bias, ‘A’ and ‘B’ wayline points
are plotted over 70 m/230 ft, driving the vehicle at 2 kph or