Lister Petter T Series, Руководство оператора

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18
tHe eCo28 alternator operators' Handbook
and a very low resistance in the
opposite direction. A faulty diode will
show either a very low resistance, or an
infinite resistance in both directions.
Once the whole sector, or the whole
bridge, is replaced, remember to
tighten the screws with a suitable
tightening wrench and to strictly comply
with the polarities and the wiring
diagrams.
6.5 tHe exCIter
1. Remove the front cover, rotor
and bearing as described in "6.1
Bearings".
2. To remove the exciter rotor, use a
suitable puller as shown below.
Figure 6.5.1 Typical Puller Tool
6.6 tHe VoltaGe reGulator
The SR7/2-G voltage regulator is an
integral part of the alternator.
Figure 6.6.1 SR7/2-G Voltage Regulator
replacing the aVr
1. Carefully note the position of each
terminal board wire and remove
them.
2. Remove the four regulator retaining
setscrews.
3. Fit the new regulator into position.
4. Replace and tighten the four
retaining setscrew.
5. Replace the terminal board wires.
6.7 resIdual VoltaGe
CHeCk
The residual voltage check is applied
to ensure that the generator is not over
excited. If it is over excited, although it
still rotates at nominal speed there is no
voltage present at the alternator main
output terminal board.
1. With the set not running, remove the
terminal cover.
2. From the relevant diagram in "Section
08. Electrical Wiring Diagrams"
identify the positive (+) and negative
(-) terminals on the AVR.
3. Using a 12 volt battery with two
wire connected with a 30Ω in-series
resistance momentarily connect
the two battery connecting wires
to the previously located + and -
terminals.
Ensure the polarities are matched.
(+ terminal of regulator with battery
+ and - terminal of regulator with -
battery terminal).