TAIYO LX Series Generator Common Troubleshooting and Maintenance Guide

7.2 Unbalanced load capacity

Allow 20% negative sequence current (relative to rated current). Negative sequence current can cause rotor heating and vibration. When the three-phase voltage imbalance is greater than 5%, the load distribution or stator winding should be checked.

7.3 Short circuit current capability

LX-E and LX-H: 250% rated current for 2 seconds at 50Hz; 300% at 60Hz for 2 seconds.

LX-G: Does not have the ability to sustain short circuits.

Fault handling: If the generator cannot rebuild voltage after a short circuit, the possible reasons may be that the rotating rectifier is burnt out or the residual magnetism of the exciter disappears. A 12V battery can be used to instantly apply direct current (positive and negative polarity to be confirmed) to the stator of the exciter for magnetization.

Daily maintenance checklist

Every 100 hours of operation:

Check and clean the ventilation openings and heat sinks.

Check the insulation of the output cable and the torque of the connecting bolts.

Check the appearance of AVR and rotating rectifier for signs of overheating.

Every 250 hours or every month:

Measure the insulation resistance and record it.

Check the temperature and vibration of the bearings.

Test the voltage regulation range of AVR (rotate the voltage regulation potentiometer when unloaded and observe whether the voltage change is linear).

Every 2000 hours or year:

Replace the bearing grease (for models with oil injectors).

Calibrate the voltmeter, frequency meter, and protective relay.

Record the no-load and full load waveforms with an oscilloscope and establish a benchmark file.

Every 5 years or during major repairs:

Disassemble and inspect the stator winding ends and binding straps.

Check the diodes and varistors of the rotating rectifier.

Evaluate the magnetic properties of the PMG rotor (if it is LX-H).

Selection and Fault Prevention

If the on-site load contains a large number of frequency converters, UPS or rectifiers, LX-H should be preferred to avoid AVR loss of control due to harmonic waveguides.

If only conventional industrial motor loads are needed and the budget is limited, LX-G or LX-E are sufficient. However, it should be noted that LX-G cannot be used in situations where continuous short-circuit current is required (such as anti islanding protection in parallel with the power grid).

In high altitude (over 1000m) or high temperature (over 40 ° C) environments, it is necessary to reduce the capacity for use and consult the manufacturer for correction factors.

Parallel running generators must use AVR with droop or reactive power regulation function, and the LX series models of each unit should be consistent.