MAHA LPS 3000, Operating Instructions Manual, Page: 23 / 115

BA052301-en
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2.5.1 RPM Module (Standard)
The RPM module is used to record the RPM and oil temperature (Plug-in card CAN DRZ).
The following RPM sensors/sources can be used:
Trigger Tongs
The RPM signal is picked up at the ignition cable (spark plug or distributor ignition coil) with the
trigger tongs. The trigger tongs should be placed as close as possible to the spark plug and as
far as possible from the next ignition cable. The trigger tongs take up the high voltage signal
inductively which is conducted from the distributor to any random cylinder. The pulse is relayed
from the trigger tongs to the test box where it is converted to an RPM signal.
Attachment:
Position
(D) on the interface box.
Piezo Clamp
Piezo clamp is only used with diesel engines. The piezo clamp consists of a piezo element
which recognizes pressure differences at the lead-in and then converts them into electric
pulses. It is important that the piezo clamp which is used is suitable for only one diameter of the
fuel line and should only be placed at a straight section of the line at any cylinder (attach ground
clamp on the same injection line).
Attachment:
Position
(A) or (B) on the interface box.
Clamp W
The alternator RPM is ascertained through the clamp W. The number of pulses per rotation at
the alternator (proportional to the crank shaft RPM) should be known or must be determined by
an external measuring device. This is necessary because individual vehicle models have
different transmissions between crank shaft and alternator. The RPM determination at the
clamp W is only used with diesel engine vehicles.