Mercedes-Benz Metris BM 447, Инструкция по корпусу и оборудованию

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Mercedes-Benz Body & Equipment Guideline for Metris - BM 447, Version November 27, 2015.
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Please observe the revision notes compared to 09/18/2015 ! Only print out complete sections of the current version!
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9.4 Interfaces/electrical lines
9 Electrical system
All electrical equipment fitted must be tested in accor-
dance with EU Directive 72/245/EEC and must bear
the "e" mark.
The following points must be observed if you intend to
have other alternators retrofitted:
• On no account should the installation of an alterna-
tor impair vehicle parts or their function.
• The battery (
e
Page 99) must have sufficient
capacity and the alternator (
e
Page 105) must
generate sufficient power.
• The alternator circuit must be provided with addi-
tional fuse protection 5.5.1 “Electric wiring/fuses”
(
e
Page 53).
• The line cross-section must be dimensioned
according to the current level drawn, see
5.5.1 “Electric wiring/fuses” (
e
Page 53). The
higher power draw may necessitate the replace-
ment of the starter/alternator wiring harness.
For this, we recommend the use of genuine
Mercedes-Benz parts.
• Electrical lines must be routed correctly
(
e
Page 102).
• There must be no impairment of the accessibility or
easy maintenance of installed equipment.
• There must be no impairment of the required
engine air supply and cooling (
e
Page 72).
• The guidelines of the equipment manufacturer
for compatibility with the basic vehicle must be
observed.
• The operating instructions and the maintenance
manual for the additional assemblies must be sup-
plied when handing over the vehicle.
9.4.7 Vehicle speed signal
The "Highline" and "Lowline" instrument clusters output
an electronic speed signal at pin 9 of the instrument
cluster connector.
The speed signal (positive to ground) acts as a distance
and speed signal for external electronics, e.g. taxime-
ters or speed-dependent volume controllers. The signal
is protected against short-circuit to ground and battery
voltage and is not monitored.
The signal is output at 4 pulses per meter = 3.28 ft. The
pulse width is 4 ms.
At 112.5 km/h = 70.31 mph, the pulse duration is the
same as the pulse pause. This 1:1 ratio is maintained
for higher speeds. This means that, at higher speeds,
the pulse length and the pause length become shorter
at the same time.
T
High
T
LOW
T
LOW
N30.00-2014-00
Ratio of pulse duration/pulse pause
Vehicle speed signal (Imax = 20 mA):
THigh Ua ≥ 8 V
TLow Ua ≤ 1 V