Its 230kvaperkins generator it starts normally,but after thirty minutes it shuts dawn automatically indicating low frequency

Six steps of start-up Shangchai generator set :
A.Unscrew the deflation screw on the fuel injection pump, use the fuel hand pump to remove the air in the fuel system, and fix the adjusting control handle on the throttle position of the suitable starting speed;
B.Pressthe generatorstart button to start the diesel engine. If the diesel engine can't start in 10 seconds (up to 15 seconds), it should wait for 1 minute before starting for the second time. If it can't start for three consecutive times, should check and find out the cause of the failure;
C.After diesel generator set start up, the no-load speed gradually increases to 1000-1200 r/min (note not to run at low speed for a long time). After the diesel engine is preheated, the speed is increased to the rated speed. When the outlet water temperature reaches 55 degrees Celsius and the oil temperature reaches 45 degrees Celsius, full load operation is allowed;
D.After starting the diesel engine, pay close attention to the reading of oil pressure gauge (2.5-3.5kg/C?in normal operation). If the oil pressure gauge does not indicate, stop immediately and check whether the ammeter has charge indication;

E.After the diesel generator set is put into normal operation, should observe the changes of water temperature, oil temperature and oil pressure at any time, and should handle the reading of power meter, frequency meter, ammeter and voltmeter in time if abnormalities are found;
F.When each instrument of the genset indicates normally, can turn on the load switch to send power to the load. With the change of load of the genset, if the frequency and voltage are not within the prescribed range, should adjust the frequency and voltage in time to maintain the rated value. It is strictly prohibited that the genset carry load at low speed, so as to avoid damage to the equipment.

P0625 - Generator Field Terminal Circuit Low Description: The powertrain control module (PCM) monitors generator load from the generator/regulator in the form of frequency. The concern indicates the input is lower than the load should be in normal operation. The load input could be low when no generator output exists. Possible Causes:

• GENRC circuit short to ground
• GENLI circuit short to ground
• Open B+ wire during operation
• Low system voltage
• Broken generator belt
• Damaged generator/regulator assembly

Diagnostic Aids: Verify the battery voltage is 14.5 volts. Verify the generator/regulator has the correct part number. Application Key On Engine Off Key On Engine Running Continuous Memory All GO to Pinpoint Test HY .

Hi Jon,
please check the diode plate.
i think one diode is short cct,
regards.
nuwan

Check for floating debris in fuel tank possibly restricting fuel flow thru screen on bottom of fuel pickup;

My Honda generators have a low oil sensor that automatically shuts them down when a low oil level is detected. I keep a quart handy and top off the oil, and they start and run fine.

Power tools CAN draw heavy loads if the voltage or frequency is off. Both of those CAN be a fault of the generator.

Check the frequency by plugging in a clock with a moving second hand and time it for 10 minutes against a quartz clock. ALSO do a voltage check with another voltmeter.

The 5500 Watt generator should hold 40 amps. Power tools with induction motors like some table saws take a large starting load near this value AND would be sensitive to low voltage AND especially low frequency, both of which will cause much higher current draw.

One MIGHT have to resort to put an oscilloscope on the output to make sure the waveform of the AC output is normal..

I install and work on these everyday. If you hooked up the transfer switch you probable have a control wire wrong. check the utility power sense wire. That lets it no when to start in auto. it could be a relay or fuses. or a control board.

the flashing O/D light usually means you have a bad speed sensor that sends speed info to the engine & trans computer.

Vehicle Speed Sensor The vehicle speed sensor (VSS) (Figure 42) is a variable reluctance or Hall-effect sensor that generates a waveform with a frequency that is proportional to the speed of the vehicle. If the vehicle is moving at a relatively low velocity, the sensor produces a signal with a low frequency. As the vehicle velocity increases, the sensor generates a signal with a higher frequency. The PCM uses the frequency signal generated by the VSS (and other inputs) to control such parameters as fuel injection, ignition control, transmission/transaxle shift scheduling and torque converter clutch scheduling.
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Vehicle Speed Sensor The vehicle speed sensor (VSS) (Figure 42) is a variable reluctance or Hall-effect sensor that generates a waveform with a frequency that is proportional to the speed of the vehicle. If the vehicle is moving at a relatively low velocity, the sensor produces a signal with a low frequency. As the vehicle velocity increases, the sensor generates a signal with a higher frequency. The PCM uses the frequency signal generated by the VSS (and other inputs) to control such parameters as fuel injection, ignition control, transmission/transaxle shift scheduling and torque converter clutch scheduling.

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Some trans use an OSS, Output Shaft Sensor instead of a VSS. Depends on which trans you have, 4R100 or 4R70W

Transmission Control Switch (TCS) and Transmission Control Indicator Lamp (TCIL)
The transmission control switch (TCS) is a momentary contact switch. When the switch is pressed, a signal is sent to the powertrain control module (PCM) to allow automatic shifts from first through fourth gears or first through third gears only. The PCM energizes the transmission control indicator lamp (TCIL) when the switch is off.

The TCIL indicates overdrive cancel mode activated (lamp on) and electronic pressure control (EPC) circuit shorted (lamp flashing) or monitored sensor failure.

Output Shaft Speed (OSS) Sensor
The output shaft speed (OSS) sensor is a magnetic pickup, located at the output shaft ring gear, that sends a signal to the powertrain control module (PCM) to indicate transmission output shaft speed. The OSS is used for torque converter clutch control, shift scheduling and to determine electronic pressure control.

your micrwave may run fine at 110 but it draws more power than the generator is putting out when the magnetron kicks on which is the part that creates the microwave causing the food to heat up. In other words the amperage is too low for the microwave. Amperage is what matters not voltage.