131
Speedometer
ПА
8046-4
П
is a complicated electronic device the truck driving safety
directly depends on. It is recommended to calibrate the speedometer in the “Ural” Automo-
bile Works” OE JSC regional service centers. In case it is impossible, speedometer calibra-
tion should be performed strictly observing instructions below.
5.6.1.1 Speedometer calibration:
1. Place the tuck on the zero mark of the previously measured and marked straight road
section. Road section can be a whole multiple part of 1000m, ex.: 100m, 50m or 20m, to simplify
the calculation.
2. Press the button on speedometer back part for data entering. Holding the button
pressed start the engine. Four seconds after the engine start release the button. The signs «
П
- - - -
» appear on digital display.
3. Enter the access password necessary for coefficient change. Blinking symbol means
readiness for changes. Enter the numerical- alphabetical symbol by short pressing (less than 1 se-
cond). Enter the previous password first which is written under the speedometer sealed cover, ex.:
«
П
0 0 0 1»; after that enter the new password (any four-digit number), ex.: «
Н
0 0 0 1».
Warning! Further speedometer calibration is impossible when the password is lost!
For entered password registration it is recommended to record the passwords into the regis-
ter and change them periodically.
4. Enter the calibration mode by short pressing (“0” should appear in the extreme right
position). Driver should drive the truck at low speed for defined road section and stop the truck at
the assistant command by the end mark. The number of pulses counted during passing the defined
road section will be presented on the speedometer digital display. To make the calculation more
precise, carry out several measurements by reversing the truck and writing down numerical values
at the initial and end marks (values should be summed up). Mean value is calculated after several
measurements. Number of pulses per each drive of defined section is calculated by subtraction of
the previous value from the subsequent one. Obtained pulse mean is multiplied by the number
which is equal to a truck run, i.e. a multiple of 1000 meters, according to the formula stated be-
low:
L
Đ
Ę
*
1000
=
where L — truck run;
Р
— indicated by the device pulse number.
For example: if speedometer recorded 504 pulses per 100 m of run then enter the calibra-
tion coefficient equal to 5040 (e.i. 504x10). Other example: if speedometer recorded 99 pulses per
20 m of run then enter the calibration coefficient equal to 4950 (e.i. 99x50) etc.
5. Programmable coefficient entering:
