User`s guide

Configuring the DVR
700-0058 R001 3–21
To calibrate speed:
1. Press the
POWER button only once to begin calibration.
It takes approximately two seconds for the system to be ready to start
calibration. After driving one mile, the
SPEED PULSE COUNT may be anywhere
from 2500 to 150,000, depending on the type of vehicle speed sensor being
used.
2. Press the
POWER button again to save the calibration value.
The
DVR returns to the GPS/Speed menu and the new calibrated speed pulse
count is shown.
SPEED PULSE
COUNT
The EX4 Plus 35 DVR can record vehicle speed by counting
the number of pulses received either from a vehicle speed
sensor or a vehicle Transmission Control Module (
TCM). The
DVR must first be calibrated to the vehicle’s speed signal by
driving for one mile (kilometer) in Calibration Mode. The
DVR
counts the pulses from the vehicle’s speed sensor and then
converts a pulse rate into speed. The actual distance driven
during calibration determines the unit of the speed. For
example, driving one mile during calibration results in speed
being in
MPH. Driving one kilometer results in KPH. The SPEED
PULSE COUNT increments as the vehicle travels.
2500 to 150,000 003000
CALIBRATE SPEED When calibrating speed, it is best to use known road markers
to determine a mile (kilometer) as reading the odometer may
introduce errors.
Not applicable Not
applicable
Table 3-13 GPS/SPEED configuration items
Menu Item Description Values Default
Important: You can change the speed pulse count to either fine tune the speed display,
or to set a known value from a similar vehicle. This is useful if a fleet consists of several
models of the same bus. By calibrating one bus, the speed pulse count can then be entered
into the DVRs for all of the similar buses. However, if a DVR is moved from one bus to
another, the speed may have to be recalibrated due to differences in transmissions, tires,
and other factors.