Just like UPS systems, generators are hugely important for power protection. Widely used in industrial settings that require uninterrupted and high volumes of power, they also are regularly found on construction sites, at festivals, camping sites, sporting arenas and hotels. Many businesses rely on them, and an increasing number of homes now do as well. Specialists in building generators such as SDMO Industries provide generator solutions for an incredibly wide range of applications – from handheld portable units to enormous industrial generator sets.

It is important to realise, however, that certain considerations must be made in order to keep them running in proper order. Beyond the obvious, such as keeping the engines well-oiled and maintained, one of the most important is being aware of the ‘load’ (the amount of power being consumed by connected elements) of the generator. One might think that being aware of the load is crucial to avoid overloading the generator. However, once a generator with sufficient capacity has been chosen for the application, most diesel generators can comfortably run at 100% load for some time. In fact, it is running a generator at low or no load that poses a larger danger.

How Generators Work

Diesel generators (or generator sets aka ‘gensets’, as they are commonly known in professional circles) consist of a diesel engine – which essentially works the same way as a diesel engine in heavy vehicles – and an electrical generator. People are often surprised to learn that in these generator sets – which are designed to provide power to sites not connected to the power grid, supply emergency power when the grid fails, or to supplement power during peak usage – the electrical generators do not actually produce energy. Instead, they convert the mechanical energy produced by the diesel engines to electrical energy. As a result, generators follow a rule of internal combustion engines – they must have a certain load attached to them in order to operate properly. Running generators on low or no load can have a range of results that can lead to problems, from inefficient running to serious damage or even complete failure.

The Results Of Low Load Or No Load Operation

The abilities and requirements of generator sets will vary from generator to generator, but there are some widely accepted guidelines.

It is mostly agreed that generators are to be run at a minimum load of 30% of maximum capacity and recently several manufacturers have advised not to load generators below 50% (please check your minimum level with our technical team).

This is an absolute minimum and far from ideal – generally, a load of 60-75% of maximum capacity is considered preferable. No load operation, other than for short diagnostic runs such as checking for proper idle, should be avoided at all costs. The consequences of low or no load operation include:

Low Cylinder Pressure

Diesel engines work by compressing hot air to an extreme extent (far more than gasoline engines) so that when fuel is introduced into the cylinder, it ignites without the need for a spark plug. As a result, high cylinder pressure is integral to the proper working of the engine. When a generator is being run at low load, low cylinder pressure results in poor combustion, decreasing the efficiency of the engine. The poor combustion causes a cyclical issue – soot and unburned fuel residue clogs the already poorly-sealing piston rings, making the low-pressure problem even worse.

Low Temperature

At low load, engines cool and run at a temperature insufficient to create proper combustion. This also causes fuel to be only partially burned. In addition to deposits, this can lead to a lot of exhaust emissions. Exhaust is the familiar white smoke seen in poorly operating diesel engines – smoke which is dangerously high in hydrocarbon emissions.

Glazing

This is a phenomenon that is often a major culprit behind diesel engine damage. Hot combustion gases escape past the piston rings and instantly burn the oil lubricating the cylinder walls. The result is a smooth, enamel-like glaze along the cylinder walls, which covers the grooves meant to hold the cylinder-lubricating oil and transport it to and from the crankcase. This results in increased wear and tear due to under-lubrication and increased oil consumption. However, it is not the only low load side effect that causes this problem.

Lower Oil Performance, Higher Oil Consumption

Low load operation wreaks havoc on the engine’s oil distribution system in a number of ways. Hard carbon deposits formed as a result of poor combustion cause bore polishing, destroying the honing marks (grooves) for the oil. The oil burns and oil consumption increases. Due to the poorly sealing piston rings, unburned fuel contaminates the lubricating oil, as does condensed water and residue, which cause a destructive acid build up.

Increased Pollution

The white smoke caused by unburned fuel due to low temperatures has already been mentioned. However, this is not the only increase in pollution caused by low load operation. Oil leaking past the poorly-sealing piston rings into the combustion chamber is burned and causes distinctive blue smoke, while black smoke is the result of damaged injectors.

There are a host of additional issues caused by low or no load operation, including and the specifics of each case or low or no load will determine the severity of each issue:

• Increased pressure in the crankcase.
• Excessive wear and oil leaks in the turbocharger (if one is present).
• Carbon deposits on numerous surfaces including valves, pistons and the exhaust manifold.
• Engine exhaust slobber – black oily liquid leaking from the exhaust manifold.
• Engineer call out required.

Effect of Low Load Operation on Generators

The above damaging occurrences have a cumulative effect on generator sets. First, users are likely to observe unexplained power losses and intermittent poor performance. This is due to the inefficient operation as well as highly accelerated wear on components. Soon, components will begin to fail, resulting in unscheduled maintenance and increased downtime. At a certain point, glazing and carbon buildups become so extreme that completely striping the engine, reboring the cylinders, and machining new honing marks is the only solution. Regularly running generators at low or no load will, without a doubt, eventually result in total generator failure.

How to Prevent Low Load Operation Damage

At some point, generators will undoubtedly need to be run at less-than-optimal load. When it is not a regular and prolonged occurrence, this does not have to cause any damage whatsoever to your generator.

No load operation should never exceed 15 minutes. For low load operation, you should contact your manufacturer or your account manager at Critical Power Supplies Ltd, who will be able to advise you on safe low load operation values and durations. After low load operation, generators should be operated with an increased load for a short period to raise temperature and pressure. Once a year, a ‘load bank’ test should be run, where the generator is run for several hours in order to eliminate all deposits.

Properly run and maintained, generators can ensure that you will never be left without power regardless of power availability from the grid. Combining generators and UPS systems, meanwhile, provides both uninterrupted power and protection of sensitive equipment from power surges and fluctuations. Experts like the highly experienced professionals at Critical Power Supplies can help you design an affordable solution customised for your needs. Contact us to find out more information about our consultancy services.

5 Benefits of Hiring a Generator Maintenance Technician

Your generator is a durable machine that keeps power flowing to your critical business systems during an outage. Large commercial generators are designed to last for many years, but even the best generators need regular maintenance service. The best way to ensure that your generator receives the attention it needs is by hiring a skilled generator maintenance technician. Here are the top benefits that you will gain by bringing in a professional for the job.

1. Access Expert Knowledge

Most business owners don’t have the technical knowledge necessary to service their generator. A generator technician will have the proper training and industry knowledge to handle any maintenance that your power system requires. Plus, with a professional, you won’t have to worry about spending time troubleshooting or wasting money on unnecessary repairs. You can focus on running your business while a qualified technician takes care of the generator for you. At Valley Power Systems, our specialists have worked with many makes and models of power systems, and we can quickly assess your unit and determine precisely what services it needs to run optimally.

2. Get Early Diagnosis of Issues

Working with a professional can help you identify issues with your unit sooner rather than later. When performing maintenance, your technician will inspect the system thoroughly and test it for proper function. They will have the industry training to identify even the most minor issues with a generator. Even a leaky hose can cost your business a lot of money in wasted energy, so it’s important to take care of any repair needs as soon as possible. By handling small issues before they have a chance to progress into larger problems, you can help avoid costly repairs later down the line. This can potentially save your business thousands of dollars over the life of your power system.

3. Improve Generator Lifespan

An industrial generator is a significant investment for your business, so you want to make sure that it will last as long as possible. Having a technician perform maintenance on a regular schedule is the best way to maximize its lifespan. After so many years, your unit will begin showing signs of wear and tear and may not work as efficiently as it once did. Periodic maintenance can help minimize the effects of wear so that you can get more usable years out of your power system. With the right maintenance plan and optimal environmental conditions, a standby diesel generator can last for 20 years or more!

4. Keep Operations Running

When an outage happens, you want access to a reliable power solution to keep your business running without any disruptions. Having your generator serviced regularly can help you make sure that it will work when you need it most. You don’t want to be troubleshooting a generator in the middle of a power failure. With a properly functioning unit, you won’t have to worry about losing money on stalled operations.

5. Have Peace of Mind

With a trained technician handling your generator service, you can minimize the risk of unexpected shutdowns. Your technician will alert you to any generator problems in advance so that you can address them right away. You can have peace of mind that your unit will work properly during a power outage.

When Does a Generator Need Maintenance?

The generator’s maintenance intervals will depend on a variety of factors. Manufacturers generally recommend maintenance be performed after so many continual service hours, such as after 50 running hours. There are certain situations when maintenance may be needed more often than recommended, including:

• After severe weather events like heavy wind, rain, or snow
• After a period of heavy system usage
• When the generator begins to show signs of reduced efficiency

If you’re not sure when your generator needs maintenance, be sure to check with your unit’s manufacturer or your local generator technician at Valley Power Systems. We provide all of the services that your generator needs to remain operational for many years to come.

Generator Maintenance

Your technician should perform certain maintenance tasks every time they service the generator. Doing these on a regular schedule will help reduce wear and tear and improve the overall efficiency of your power system. These include:

Changing the oil

Oil works to keep your generator’s engine clean, cool, and lubricated, but it loses its effectiveness over time. Regular oil changes can go a long way toward extending the lifespan of your power system.

Cleaning filters

When filters become clogged, debris can enter the generator engine and damage its internal parts. Clean filters will keep out dust, dirt, and other small particles to keep your power system running smoothly.

Refilling coolant

Coolant helps to control the temperature of your engine. Without enough quality coolant, the engine would overheat and possibly cause irreparable damage. The levels should be checked at every maintenance inspection.

Checking fuel

You want to ensure that you’ll have enough fuel should an outage occur, so the fuel level should be checked regularly.

Testing the system

If you don’t rely on your generator all the time, you might not notice any issues with it right away. That’s why it’s important to test the system periodically. Your technician will power on the generator and check it for proper function.

Inspect hoses and fittings

A loose or leaky hose or fitting can make your generator work much harder, which will ultimately decrease its efficiency. Your technician should inspect these thoroughly to make sure they don’t need to be replaced.

Call a Valley Power Systems Generator Technician Today

Need a generator service? Valley Power Systems has highly trained technicians ready to assist you with any generator problem. From general maintenance and diagnostics to complex repairs, we’ve got you. If you’ve experienced generator failure, our factory-trained and certified technicians will ensure your power system is up and running in no time. Contact our knowledgeable staff to explore your generator options today.

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