Troubleshooting

Unit Not in Auto

Check that the AUTO/RUN/OFF switch is in the AUTO position for automatic starting or the RUN position for manual starting. If the switch is in the OFF position, investigate why it is set to OFF before switching to AUTO or RUN and attempting to start the unit (i.e., Lock-Out/Tag-Out, maintenance work, etc.)

Weak or Dead Batteries

Weak or dead batteries are the cause of 80% of generator failures to start. Dead or low-charged batteries are a common occurrence and may result from an old battery or a faulty battery charger. 

Lead-acid batteries deteriorate over time and require maintenance. Even maintenance-free batteries will lose their effectiveness over time, and all lead-acid batteries have a life expectancy of approximately 4 years. Routine maintenance and testing can help detect a dying battery, and we recommend that batteries be replaced every 3 years.

Battery chargers are also sensitive electronic devices that are subjected to a harsh environment, and therefore are prone to failure. Battery chargers should be checked weekly on systems that involve life safety or critical loads, and at least monthly on other systems.

Fuel Problems

Lack of fuel or poor fuel quality is another common reason that generators fail to start or shut down during operation. 

Fuel quality should be checked as part of the routine maintenance plan. Diesel-fueled units may experience water in the system or other contaminants that can clog filters, fuel lines, and injectors. In diesel systems, checking the main and day tanks for water or sending a fuel sample to a lab for analysis periodically will help determine the fuel quality. Poor quality fuel should be replaced with fresh fuel. In some cases, it may be possible to add fuel treatments to help preserve or revitalize the fuel. Diesel fuel cleaning or polishing is another option for ensuring that the engine has clean fuel.

Lack of fuel will affect both diesel and gaseous units and may be due to a lack of storage, leaks, or problems with fuel delivery from suppliers or bulk fuel storage tanks. Confirm that sufficient fuel is available. Check that fuel shutoff valves are open. Check that day tanks and fuel pumps are operating correctly.

For the most part, fuel leaks relate to human error but can be caused by deteriorated fuel lines or tanks or faulty pump equipment.

In newer diesel engines that are not exercised on a regular basis, fuel can bleed back into the tank and the system loses prime. Today's rigorous emissions requirements make high pressure fuel systems more prone to air, impacting the ability for the genset to start up. Older generators that experience this problem may have a leak in a fuel line or check valves that are not properly holding the fuel in the engine.

It is always possible that the fuel level gauges have stopped working properly. The gauge may get stuck in position so it is important to visually inspect or use a measuring stick to check the fuel level periodically. 

Engine Cranks But Fails to Start

This indicates a possible fuel system problem. The engine stops cranking or the engine runs and then shuts down.

• Check for empty fuel tank, fuel leaks, or plugged fuel lines and correct as required.
• Check for dirty fuel filter and replace if necessary.
• Check for dirty or plugged air filter and replace if necessary.
• Check the oil level, lines, and filters and correct as necessary.
• Reset the control and restart after correcting the problem.
• Contact us to speak with a technician if none of the above.

Low Engine Temperature

Indicates engine coolant heater is not operating or is not circulating coolant. Check for the following conditions:

• Coolant heater not connected to power supply. Check for blown fuse, open circuit breaker, or disconnected heater cord and correct as required.
• Check for low coolant level and replenish if required. Look for possible coolant leakage points and repair as required.

Engine Will Not Crank

Indicates possible fault with control or starting system. Check for the following conditions:

• Fault lamp on. Correct fault and reset control.
• Poor battery cable connections. Clean the battery cable terminals and tighten all connections.
• Discharged or defective battery. Recharge or replace the battery.
• Contact us to speak with a technician if none of the above.

Engines will usually protect themselves from catastrophic failure by shutting down when the oil pressure drops below an acceptable level. They may also send a pre-alarm fault code when the oil pressure has dropped below the normal operating range and may shut down if corrective action is not taken.

We recommend that the oil levels be checked regularly and maintained as close to possible to the dipstick FULL mark. The most accurate readings are taken 10 minutes after running the unit under load and shutting down.

Once the unit has stopped, check the oil level, lines, and filters. If the oil system is OK, but the oil level is low, top off the oil. Reset the alarm on the control panel and restart.

Low coolant levels due to cooling system leaks are the most common reasons that engines fail or shut down due to overheating. High Engine or Coolant Temperature pre-alarms indicate that the engine temperature has risen above the normal operating range, and the unit may shut down if corrective action is not taken. The unit will normally shut down if the engine temperature has exceeded the allowable limit or the coolant level is low to protect from catastrophic failure.

If the unit is in Pre-Alarm and still running and cannot be shut down, do the following:

• Reduce load, if possible, by turning off non-critical loads.
• Check air inlets and outlets and remove any obstructions to airflow.
• Open doors in the generator area to increase ventilation.

If the engine has stopped or can be stopped:

• Check the coolant level and replenish if low. Check for any coolant leaks and repair if necessary.
• Check for obstructions to cooling airflow and correct as necessary.
• Check the fan belts for slippage or deterioration and tighten or replace as necessary.
• Reset the control panel and restart after locating and correcting the problem.

The air, oil and fuel filter elements must be changed per manufacturer’s recommendations or whenever necessary due to site or operating conditions. Any blockage will restrict flow and result in reduced performance. Air and oil filter blockages also contribute to excessive engine wear. Check air intake and correct as required. Clean or replace filters and screens.

Poor quality fuel can also contribute to low power or the loss of power. Check the fuel and replenish with fresh, proper quality fuel.

Low engine power or generator under frequency can be the result of a fuel system problem. Check for dirty or clogged air filter and adequate fuel delivery. If the fuel system requires adjustment or it is suspected that fuel delivery is inadequate, contact us to speak with a service technician or schedule a service call.

It is also possible that the engine is overloaded. Reduce the load to the proper level.

Required maintenance, such as a tune-up or an overhaul, may also contribute to poor engine performance. Perform the tune-up procedures or schedule a technician to come out and repair or overhaul the unit.  

Regular testing under full load will identify issues that could prevent the generator from carrying its rated load. Standby/emergency installations should be regularly exercised for 30 minutes with a minimum 30 percent electrical load at least once a month. For critical standby applications, this is often increased to once a week. 

Exercise the unit regularly under load and consider scheduling a load bank test to help identify the problem and clear up any "wet-stacking" that may be present.

Indicates possible fault with voltage regulator.

• Verify output with another meter. If OK, check meter. If OK, check meter fuses.
• Regulator fuse is blown. Replace fuse. If voltage build-up causes fuse to blow or the fuse blows again, an experienced technician may be required to further troubleshoot the cause.
• Check rotating rectifier for damaged diodes. Replace all diodes if any are failed.
• Contact us to speak with a technician if none of the above.

Engine Does Not Start

Engine start wires not terminated properly. Check engine start connections for loose or broken wires.

Generator is in the OFF position or the Emergency Stop button is activated.  Investigate why the engine control switch was turned off and then physically reset the control switch.

Engine Does Not Stop

Timing cycle not complete. There are settings that control the amount of time for the ATS to start the engine, transfer the load to the generator, re-transfer the load back to utility when normal power returns, and to shut the generator off after a cool-down period. The typical cool-down period is 5 minutes.

If normal power has returned and the load has been re-transferred back to normal power, check to see if the unit shuts down after a cool-down period.

If the load is still on the generator source, it is possible that the utility power quality is still unstable and the ATS is operating correctly by not re-transferring the load. 

It is also possible that the transfer mechanism is hung up or the timer is not working properly and will require further troubleshooting by an experienced technician.

ATS Will Not Transfer to Emergency

Emergency voltage or frequency is not within the acceptable parameters. The ATS senses when the generator is up and running and producing the correct voltage and frequency. If there is a problem with the engine or the electrical output from the generator, the ATS will not transfer the load.

It is also possible that there are broken wires or that wiring harnesses have come loose.  Check for loose connections.

Timing cycle is not complete. Check the Time to Transfer to Emergency timer settings.

ATS Will Not Transfer to Normal

Normal voltage or frequency is not within the acceptable parameters. Check the utility power and utility breakers or disconnects.

It is also possible that there are broken wires or that wiring harnesses have come loose.  Check for loose connections.

Timing cycle is not complete. Check the Time to Re-Transfer to Normal timer settings.

Transfer switches also require routine maintenance by a qualified service technician. For problems not listed or to schedule ATS maintenance, please contact us.

A line circuit breaker is mounted to the generator output box. If the load exceeds the circuit breaker current rating, the line circuit breaker will open, preventing the generator from being overloaded. 

If the circuit breaker trips:

• Locate the source of the overload and correct as necessary.
• Manually reset the breaker to reconnect the load to the generator.

If the circuit breaker continues to trip, contact us to speak with an experienced technician for further troubleshooting.