Principle Of Operation - VDO KIMAX Instrucciones De Uso

Installation and operating instructions

Principle of operation

Many modern commercial vehicles and trailers/
semitrailer are equipped with air suspension with
automatic level control.
KIMAX takes advantage of the linear correlation
between the air pressure in the suspension sy-
stem and the axle load.
On suspension systems with two independent air
suspension circuits per axle or axle group, the
KIMAX variants with two sensor connections
measure the pressure in both circuits.
KIMAX measures the air pressure in the suspen-
sion system and calculates the current axle load.
Calibration
Despite the linearity between air pressure and
axle load, there are significant deviations bet-
ween different vehicles. This is due mainly to the
differences in air cylinder size and their mechani-
cal design. To allow for these differences, KIMAX
can be calibrated after its installation.
For correct calibration of the device electronics,
two reference points are required:
Unladen weight (LO) and - where possible - the
maximum weight (HI).
Using these two measurement points, KIMAX
calculates the complete air pressure/axle load
curve and shows the current axle load on the dis-
play.
With individual calibration, an accuracy better
than ± 2 % of maximum load can be achieved.
An accuracy below this value is due either to in-
correct calibration or to excessive friction bet-
ween the mechanical components of the
suspension.
Alarm value settings
KIMAX features two individually adjustable alarm
value settings.
If alarm value 1 (A1) is exceeded, the display
flashes.
If alarm value 2 (A2) is exceeded, an internal re-
lay is actuated.
The relay signal can be read and transmitted to a
recording or other device (e.g. TCO/OBC).
© Siemens VDO Trading GmbH
Introduction
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