LTC Repair Lombardini Engine Troubleshooting - Wacker Neuson

Electrical Troubleshooting Procedures LTC Repair
6.10 Checking the Stator Windings
See Graphic: wc_gr003518
WARNING
Electric shock hazard. Only qualified personnel should conduct this
test.
The stator consists of three separate windings. Two of the windings
are tapped for power. The third provides excitation to the rotor. This
third winding is known as the excitation winding.
To check the stator windings, carry out the following procedure:
6.10.1 Turn off the lights and shut down the machine.
6.10.2 Remove the screws that secure the control panel cover to the control
box. Remove the control panel cover and place it securely on the
fender of the trailer. So it will not fall when the engine is started.
6.10.3 Disconnect the wires labelled “1”, “2”, “3”, and “4” from the short
terminal strip (a). These are the stator winding leads.
6.10.4 Using the Ohms scale on a multimeter, measure the resistance across
wires labelled “1” and “2”. Also measure the resistance across wires
labelled “3” and “4”. There should be 0.4±0.2 Ohms measured across
each pair.
If 0.4±0.2 Ohms is not measured, the winding has failed; replace
the stator.
If 0.4±0.2 Ohms is measured, continue.
6.10.5 Measure the resistance (continuity) between each winding lead (wire)
and a common ground.
If resistance (continuity) to ground exists, the winding has failed;
replace the stator.
If there is no continuity (resistance) to ground, the winding is OK.
6.10.6 Measure the resistance (continuity) across wires labelled “2” and “3”.
If resistance (continuity) exists, the winding has failed; replace
the stator.
If there is no continuity (resistance) to ground, the stator windings
are OK.
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