Linz E1S10L L, Operation And Maintenance

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BEARINgS
The bearings of the alternators are self lubrificated and therefore they do not require maintenances for a period of more
than 10000 hours.
When it is necessary to proceed to the general overhaul of the generating set it is advisable to wash the bearings with a
proper solvent.
Bearing type
Alternator Driving end Non driving end
E1S10 6305-2Z-C3 6204-2Z-C3
E1S11 6207-2Z-C3 6205-2Z-C3
E1S13
6208-2Z-C3 6305-2Z-C3
SLIP-RINgS, BRUSH HOLDER AND BRUSHES
The set of collector-brush holder-brushes is designed to guarantee a safe and long service. Therefore during the use of the
alternator particular operations of maintenance to this system are not demanded for at least 2000 hours of service for the
2 poles-alternators and 4000 hours for 4 poles alternators.
In case of the de-excitation of the alternator and the consequent irregularity of the electric current supply it is necessary
to carry out the following simple operations:
1) Clean the slip ring-brushes and their corrected mechanical position.
2) Check the position of the brushes; they must be lean for all their width, within the surface of rings.
3) Check the brushes and eventually replace them if worn.
THREE-PHASE DIODE BRIDgE (Figure 11)
Normally it comes used the three-phase diode bridge for 25A - 800V.
Checkout of three-phase diode bridge
The checkout of single diode valves of rectifier bridge can be executed either with an ohmmeter or with a battery
and relative lamp as described here below.
A diode valve works regularly when:
- the resistance, calculated with an ohmmeter, is very low in one sense and very high in the other.
- with battery and lamp, it is verified that the ignition of the lamp is possible only with one of the two available con-
nections, as shown in
Figure 12: A = Lamp On, B = Lamp Off.
Note for disassembly: Before extracting the rotor from the case it is necessary to remove the brush-holder.
FAULT CAUSE SOLUTION
Alternator does not excite
1) Insufficient residual voltage
2) Connection break
3) Broken three-phase diode bridge
4) Insufficient speed
5) Windings breakdown
6) Poor contact with the brushes
1) Excite the rotor using a battery
2) Reset the connection
3) Replace three-phase diode bridge
4) Adjust speed regulator
5) Check winding resistance and replace
damaged part
6) Clean and check the collector
Low no-load voltage
1) Reduced speed
2) Poor brushes contact
3) Winding failure
4) Broken three-phase diode bridge
1) Reset speed for drive motor
2) Check, clean ar replace the brushes
3) Check resistance and replace
damaged part
4) Replace three-phase diode bridge
Correct no-load voltage but too
low with load
1) Low speed with load
2) Failed compound
3) Defective winding rotor
4) Load is too high
1) Adjust speed regulator
2) Check the compound and eventually
replace it
3) Check winding resistance and replace
the rotor if it is broken
4) Reduce the load
Correct no-load voltage but too
high with load
1) Appliances with capacitors on
the load
2) Air gap of compound too excessive
3) Defective winding compound
4) Wrong connection of phases
1) Reduce revolving speed
2) Reduce air gap of compound
3) Check winding resistance and replace
the compound if it is broken
4) Check and adjust the connection
of phases
Unstable voltage
1) Rotating mass too small
2) Uneven speed
3) Poor contact on collector
1) Increase the flywheel of the primary
motor
2) Check and repair speed regulator
3) Check and clean the slip-ring and
the brushes
Noisy Functioning
1) Bad coupling
2) Short circuit in windings or load
3) Faulty bearing 1) Check and correct coupling
2) Check windings and loads
3) Replace faulty bearing
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