As the heart of any uninterruptible power supply (UPS), the batteries represent the single most important component of the system. Yet one of the most frequently asked questions is, how do I know if my UPS battery is bad? Checking UPS battery health often begins with a self-test of the unit. But in order to avert unexpected downtime and costly repairs, batteries also require proper preventive maintenance and testing by a professional service provider.
Organizations that proactively perform UPS battery health checks can be confident that their system will perform as expected when they need it most. Keep reading to learn the important aspects of how to test UPS battery health.
What Is a Battery Self-Test?
Most modern UPS systems include what is known as a battery self-test feature. While this function is capable of providing a snapshot into overall UPS battery health, it generally doesn’t offer a complete picture. To test the battery of a UPS with this feature, be sure to follow the manufacturers’ instructions. Some UPSs will perform a self-test when they first start up, and then at specified intervals going forward.
For a battery test to be valid, it should be charged to 100% before beginning the assessment.
The most common way a UPS completes a self-test is by temporarily discharging the batteries. During this discharge, the system measures both the starting and ending voltage of the battery strings to determine if they remain within an acceptable tolerance. Should the voltage dip below a specific threshold, the self-test will end and generate an alarm. It is important to note that a UPS self-test isn’t able to determine how many volts are being produced by a single battery, only from a battery string. If one battery within the string is beginning to fail, it may continue to pass voltage along even if the individual cell is not within the recommended voltage range. Because of this, it is possible for the string to pass a self-test even if there is a failing cell. However, if the battery completely fails, the cell likely won’t pass any voltage, in which case the UPS is likely to fail the self-test and trigger an alarm.
Ideally, the optimal time to catch impending battery failure is at the beginning of its deterioration, as opposed to when it fails completely, potentially taking down your critical load with it. Once a UPS has received a failed self-test, the system and facility are at risk of experiencing potential power issues.
Why Is UPS Battery Testing Important?
It has been well documented that the battery is not only the most vulnerable part of a UPS system, but also the leading cause of load loss. In fact, up to 65% of UPS failures are battery-related. Despite their susceptibility, UPS batteries don’t have to compromise your business continuity or uptime; that’s where testing UPS backup batteries becomes paramount.
Checking UPS battery condition provides valuable insight into the health of your critical power protection systems. All batteries require regular testing in order to maximize their lifespan. Checking UPS battery health is also essential in order to safeguard your facility from the inconvenience and expense of an unplanned power outage. Although there have been many improvements in battery technology that have reduced the threat of unexpected failure ── such as advanced charging techniques, software management and firmware upgrades that add intelligence ── none of these capabilities completely eliminate the risk.
While most UPSs include built-in functionality that automatically tests batteries and will send an alarm if a fault is detected ── and more sophisticated UPS backup systems may feature some level of remote monitoring that will alert a technician to issues ── these measures only provide a general indication of the overall battery set. The best way to evaluate the health of a battery set is through external testing that assesses individual cell level. This type of UPS battery checkup procedure is generally included as part of a preventive maintenance plan, although it can also be provided as a standalone service.
There are numerous advantages to UPS battery testing, including:
Maximized uptime and business continuity
Ensuring ongoing, uninterrupted business operations is among the most critical tasks of UPS batteries. Testing is necessary to verify that batteries will perform as needed if there is a power interruption. This helps to avoid lost revenue, expensive delays, equipment repairs or replacements, data loss and decreased productivity.
Ongoing, optimal battery health
Checking UPS battery life on a regular basis yields valuable data that can be used to anticipate the need for corrective action. A routine, physical inspection by an experienced service professional can generate much more information than what is monitored by system sensors, as well as ensure that sensors are performing correctly.
Cost savings
Proactive battery testing by a service professional helps to maintain ongoing UPS battery health by identifying potential problems such as overheating, which can result in premature battery failure. The likely price tag of equipment damage resulting from an unplanned battery failure far exceeds the cost of regular UPS battery testing.
Reduced equipment failures
Regular testing of UPS backup batteries also helps confirm consistent, balanced voltage to the connected load. Not only can voltage imbalances cause major damage to UPS systems, but even slightly incorrect calibrations or equipment deterioration can result in inconsistent power or overloaded systems.
Upheld warranty requirements
While defects or waning performance of a UPS battery is typically covered under manufacturer warranty, uncovering these issues requires regular testing. To fulfill a warranty claim, the UPS manufacturer will require the submission of maintenance and UPS battery test reports on a variety of metrics, such as voltage testing, temperatures and other readings.
Regulatory compliance
Many industries are under highly scrutinized regulatory compliance mandates, and the risk of falling out of compliance can be mitigated with UPS backup battery testing. Battery test reports provide a written track record that can be supplied to regulatory agencies.
Is the Self-Test Feature Reliable?
Although a UPS self-test is a simple and convenient method that can be administered as the first step in a routine preventive maintenance strategy, more comprehensive testing is required in order to ensure the most accurate status of battery health. The UPS self-test feature is generally reliable, but its effectiveness can vary based on several factors, including:
Testing frequency
Regular testing increases reliability, so scheduling a monthly self-test will provide a better indication of battery health and enable you to schedule a replacement when a UPS battery is low.
Subsequent actions
UPS systems typically notify users of the self-test results, so it is essential to take action if any issues are identified.
Reporting accuracy
Although self-tests are designed to accurately report battery health, like any electronic system, there is always a margin of error.
Battery age and condition
The reliability of the self-test function can also be impacted by the overall condition and age of the batteries. Those approaching the end of their lifespan may not perform as expected even if the self-test comes back normal. All batteries have a limited lifespan, which is generally three to four years maximum. You can check the UPS battery manufacturing date on each battery to get an idea of when they are approaching the end of their expected lifespan.
Environmental factors
A variety of environmental conditions ― including temperature, humidity, and dust and dirt ― can negatively impact battery performance. For optimal battery health, overall UPS reliability and validity of self-test results, it is advisable to keep UPSs in a controlled environment.
The Benefits of UPS Battery Testing Services
While the self-test function can be a valuable tool to help monitor UPS batteries, it should not be the sole form of battery health measurement. Supplementing the self-test function with routine preventive maintenance will help ensure optimal performance and reliability of the UPS system as a whole. Furthermore, a technician from a professional service organization possesses the proper skills and tools to verify self-test results and complete additional assessments.
Engaging with Unified Power for UPS battery testing services puts your organization in the best position to achieve cost savings, accurate results and expert recommendations. Our highly trained technicians can provide testing, maintenance and monitoring services, as well as guidance on when to repair or replace your UPS. Our technicians can determine battery set health down to the individual string and cell, as well as test for factors such as electrolyte dry out and float voltage. From checking UPS battery capacity to load testing of UPS batteries, our extensive range of battery testing and monitoring services are available for all UPS brands and models. Even more, Unified Power’s technicians perform capacity tests in accordance with IEEE UPS battery testing standards, with results reviewed in the field by Unified Power’s technical support team. A detailed follow-up UPS battery test report is provided to the customer, which outlines performance results and, if applicable, includes recommendations for repairs or replacements.
We not only provide full and partial battery replacement services on all major manufacturers’ battery models, but EPA-approved recycling of the old batteries. We also offer battery monitoring systems that include daily reports of your battery plant’s life and notification if a battery failure is detected. Even more, our battery monitoring systems monitor cell voltages, internal resistance and temperature; provide an immediate warning of a specific failing battery; record up to 120 days of battery history to allow for trending analysis; offer remote monitoring capabilities; and help you budget for a battery replacement before it becomes an emergency situation.
Learn More About UPS Battery Testing Services From Unified Power
Unified Power is the premier national critical power service provider. In addition to our comprehensive battery service offering, we provide UPS and generator maintenance and repair services, turnkey electrical solutions, DC plant services and more. Contact us today for more information!