Ensuring an uninterrupted supply of power is an essential task for anyone running a data center. Power disruption can have various negative outcomes, from downtime to data loss. Given these risks, it is not surprising that back-up generators are standard features in data centers. Still, generators that are untested or poorly maintained can prove ineffective or useless when they are needed most. We at Titan Power are all too familiar with this problem, which is why we recommend regular load bank testing of backup generators. This is a crucial service for any data facility that needs to ensure consistent performance and protect against worst-case scenarios.
How Load Bank Testing Works
The goal of load bank testing is to place peak power demand on a generator and then determine whether the generator can produce and maintain the necessary kilowatt output. A load bank is a device that can create an electrical load and pass it on to the generator in a steady and controlled manner. This presents a useful alternative to the load that real-life power demand creates, which often fluctuates chaotically.
During load bank testing, the load device is typically placed within 20 meters of the generator and connected to it via cable. During the two-hour test, various measurements of the generator and its output are taken to yield insights into performance. These insights include:
- Whether the system can provide the necessary amount of power
- How efficiently the system functions at different load capacities
- Whether the generator can maintain a stable voltage throughout the test
- What levels the oil and fuel pressure reach
There are several types of load banks that can be used to perform this test, including resistive, capacitive, and inductive. When especially high-voltage loads must be produced, reactive load banks — which use inductive or capacitive loading or a combination of the two — are typically used to deliver the necessary load. We generally use resistive or reactive load banks, depending on each generator’s maximum power output.
A Controlled Environment and Useful Data
Although a basic test of a standby generator’s capabilities occurs any time that a data center’s power fails, load bank testing offers a few advantages. The data collected during load bank testing can provide a precise, carefully measured, and more comprehensive look at the generator’s ability to perform as needed. Additionally, this testing provides a controlled environment in which common risks associated with generator overload or failure — such as harm to other system components and business disruption, to name a few — can be effectively mitigated.
Proper load bank testing is an invaluable resource because it provides an accurate indicator of the way that the generator will perform in a real-life situation. Other methods of testing may not fully simulate the type of demand that the generator will need to meet. Even full-time generators that are used on a daily basis may perform differently than expected when faced with an emergency load, since most generators typically produce output that is far below their capacity ratings during everyday use. Load testing can provide useful insights and peace of mind, and it can also yield functional improvements.
The Negative Effects of Generator Underuse
Load bank testing can help improve the performance of regular generators as well as standby generators that are subject to regular no-load testing. When a diesel generator is quickly tested, used temporarily as an emergency power source, or simply under-loaded on a regular basis, it cannot reach its optimal temperature. This increases the risk that some fuel products will fail to burn off and instead accumulate in the exhaust, which is a phenomenon known as “wet stacking.” After a while, wet stacking can noticeably affect a generator’s performance. It can also reduce the device’s longevity.
Yearly load bank testing can counter these detrimental effects. The two-hour testing process can help a generator reach and sustain its peak power output, which means the generator will also achieve its ideal operating temperature. Any previously unburned fuel will be effectively burned off. After the test, the generator will be cleaner, primed to run more efficiently, and less likely to fail in the future. These benefits underscore why annual load bank testing is so advisable.
Planning for a Successful Test
In general, the only timing requirement for load bank testing is that it should be performed every year; however, the initial test should not be scheduled too soon after the generator’s initial installation. The generator batteries need some time to charge and reach voltage equilibrium in order for the test to yield accurate results. Conducting the testing about a week after commissioning will ensure reliable results, while any tests performed earlier may be inconclusive.
When you are planning for a generator load bank test, it’s important to remember that load devices can generate significant heat, even with the cooling systems they are outfitted with. These devices also produce moderate noise. It is often important to conduct testing away from employees and any building alarm systems that may activate easily. This ensures the test can be completed without unnecessary disruption to your regular business and building operations.
Schedule Your Test Today
Load bank testing is an affordable investment in your data center operations, especially when compared to the financial cost of emergency repairs and the less tangible cost of losing power at a critical time. Titan Power can incorporate load bank testing into your regular annual data center maintenance, and we also offer it as a standalone service. Don’t leave your data center susceptible to power failures and all of the associated complications. Call us today at 800-509-6170 for a free consultation about our load bank testing services.
