Read our response to COVID-19 (Coronavirus)
Request Service
Get a Quote


Home / UPS

Line-interactive vs Online UPS: Which system is right for you?

When selecting an uninterruptible power system (UPS), determining the optimal topology is one of the most important considerations. Because a standby UPS offers only the most basic level of protection, the majority of organizations choose to deploy either a line-interactive or a double-conversion online model. Before making this decision, it is important to understand the differences between the two topologies. Consider the following five key factors:

1. Your power environment. A line-interactive system conditions and regulates AC utility power, shielding connected equipment from five of the nine most common power problems: blackouts, sags, surges, and under- and over-voltage conditions. These models are best suited for applications where utility power is, for the most part, consistently clean. In facilities where the AC line voltage is unstable, distorted or fluctuates wildly, line-interactive UPSs will often resort to their batteries, which can reduce available runtime for an extended outage as well as require frequent battery replacement.

In applications where the power quality is less stable, an online UPS is generally the preferred solution, as it is the only type of UPS that completely isolates connected equipment from raw utility power by converting power from AC to DC and then back to AC. As such, the topology safeguards equipment from all nine common power problems; in addition to those protected by a line-interactive UPS, the online model also remedies electrical line noise, frequency variations, switching transients and harmonic distortion.

Still have questions? Get a response immediately.

Click above to get started or call 240.772.1710 for instant help.

2. The equipment being protected. When determining the optimal UPS topology, it is essential to consider the equipment it will be tasked with protecting. How sensitive are the devices? Are they critical to your organization’s availability and uptime? Knowing these basic requirements will go a long way toward establishing the topology that will best serve the application. Keep in mind that a double-conversion online UPS is the only topology to offer zero transfer time to the battery, making it ideal for sensitive and mission-critical equipment. And because this type of unit safeguards equipment from all nine common power problems, it affords the highest level of protection.

3. Your capacity requirements. How much equipment are you expecting to protect with your UPS? Generally speaking, line-interactive models extend up to around 5000 VA. Above this capacity, the topology has historically been impractical due to its larger size and greater cost. Conversely, double-conversion online models are rarely considered below 750 VA because line-interactive is more practical for smaller loads. However, when it comes to selecting a UPS within the 750 to 5000 VA power range, the functional and economic advantages of each topology aren’t always so clear-cut. Choosing the best topology within this overlap range will depend on the specifics of the installation, as well as weighing all advantages and possible shortfalls.

4. Financial ramifications. When considering the monetary investment required by the two topologies, it is critical to take into account not only the upfront price tag, but also the costs of potential downtime. For mission-critical facilities, the cost of downtime should be paramount in deciding what level of protection is required. Although a line-interactive system may be less expensive, it will not provide the same level of protection as an online system — leaving equipment more vulnerable to damage and the organization more susceptible to downtime.

5. Total cost of ownership. Another financial factor to think through is the ongoing operating and service costs that each topology requires. For instance, a double-conversion online UPS will consume more energy over time than a line-interactive model, which operates with greater efficiency. In addition to higher electricity demands, online models also produce more heat, which translates to a need for extra cooling. While these may seem like nominal charges, they can add up if an organization deploys multiple UPSs across an enterprise, or even when considering the total lifetime energy consumption of one unit. And while line-interactive UPS systems protect connected devices during a complete power outage, they don’t safeguard sensitive equipment against all power anomalies, which can lead to degradation and premature equipment failure. Service requirements can also vary between the two topologies, with certain design aspects that theoretically increase or decrease operating life and reliability.

As you can see, there is no single answer or distinct deduction when deciding between line-interactive and online UPS topologies. If you’re still weighing the pros and cons and trying to determine the optimal solution for your environment, give Unified Power a call. We would be happy to help establish the ideal power protection solution for the unique requirements of your organization and applications.

Need help deciding on a UPS? Get a free site assessment!

Click above to get started or call 240.772.1710 for instant help.

Education, UPS

Knowledge is Power: 5 Key Truths about UPS Systems

Whether you’re considering upgrading your uninterruptible power system (UPS), investigating service options for an existing unit, or simply seeking to bolster your overall power protection proficiency, one thing is certain: knowledge is power. With that in mind, we’ve compiled five important details to add to your power system repertoire:

1. All UPS are not created equal. It is important to recognize that the three primary UPS topologies — standby, line-interactive and online —provide significant differences in performance and varying degrees of protection. A standby system, also referred to as an off-line or passive UPS, delivers the most basic level of security, making it best suited for less critical applications. While the low-cost units supply battery backup during a power outage, they do not buffer equipment against many common damaging power anomalies.

A line-interactive UPS system is designed to shield connected devices from five of the nine most common power problems, including under- and over- voltage conditions. Typically used to safeguard enterprise network and IT applications, a line-interactive UPS provides more protection than standby models, with better power conditioning and regulation that helps prolong battery life.

Finally, the online or double-conversion topology delivers continuous protection against all nine common power problems, supplying consistent power quality regardless of incoming instabilities. Online UPSs are the optimal choice for critical applications or those involving highly sensitive equipment, such as data centers, communications hubs and other mission-critical installations where continuous, clean power is a business-critical requirement.

2. A UPS won’t necessarily include power conditioning. While either device can offer various forms of power filtering, the primary distinction between the two is that a UPS system has a battery, while a power conditioner does not. In addition to providing battery backup, some UPSs also combine power filtering into a single unit; however, the UPS must be either line-interactive or online topology and include true sine wave output. However, if your UPS doesn’t incorporate the necessary level of power conditioning, it is possible to add a separate power conditioner to the unit.

Need help deciding on a UPS? Get a free site assessment!

Click above to get started or call 240.772.1710 for instant help.

3. No matter how well you care for your UPS, certain components will eventually fail. While some UPS systems may last 15 or more years, there are several principal components that are subject to failure far earlier; most notably, the batteries, fans and capacitors. The majority of UPS batteries have an expected lifespan of three to five years under ambient conditions, but can fail much faster in environments that exceed a temperature of 77°F, or where recurrent power problems cause them to cycle frequently. Fans have a typical lifespan of six to seven years, and most capacitors will last seven to 10 years before needing to be replaced. To avoid unexpected downtime or damage to critical equipment, make sure you understand the lifecycle and maintenance requirements of these key UPS components.

4. Regular preventive maintenance is essential. Routine preventive maintenance has been shown to be one of the most successful and cost-effective ways to ensure the longevity — and reliability — of your UPS system. This proactive maintenance approach monitors ongoing UPS health through regular checkups, helping to ensure that the system will continue to operate at peak performance. In addition to batteries, capacitors and fans, a UPS’s semi-conductors, wiring, resistors and breakers all require regular attention in order to achieve optimal performance and efficiency. Without scheduled preventive maintenance, there is no way to mitigate the possibility of part and component failures, leaving equipment vulnerable to downtime and premature failure.

5. Maximizing UPS efficiency can lower your energy costs. Did you know that even small boosts to UPS efficiency can result in thousands of dollars in savings? That’s because high-efficiency UPS models achieve more real power while lowering power and cooling requirements— an especially important factor considering utility costs are long-term, ongoing expenses. While actual savings depend on utility rates, the size of the UPS system and the load supported, increasing efficiency by as little as 1 percent can translate to tens of thousands of dollars in annual savings. And the Department of Energy estimates that a 15,000-square-foot data center operating at 100W/square foot would pocket $90,000 per year just by increasing the efficiency of its UPS from 90 to 95 percent.

While these key factors are intended to bolster your overall UPS system knowledge, we at Unified Power also understand that UPS’s can be complex devices.

Still have questions? Get a response immediately.

Click above to get started or call 240.772.1710 for instant help.

Education, UPS

Five Critical Steps To UPS Deployment

Deploying an uninterruptible power system (UPS) is an increasingly important decision for today’s organizations, regardless of the size or sector. Relied upon to provide continuous, clean power to a connected load — as well as battery backup in the event of a power outage —UPSs are imperative to achieving uptime and business continuity. As a result, it’s important to put some thought before procuring a new solution. Because UPSs are specialized systems that must be seamlessly integrated with other equipment, it’s best to detail a thorough plan upfront. This will help facilitate a smooth deployment from start to finish, ultimately optimizing the lifespan of your unit.

Here are five factors to take into account:

1. Select the right partner. First and foremost, it is important to work with a true UPS expert who can help guide you through the entire decision-making process. Make sure the company has a solid reputation and specializes in UPS and power-related equipment.

2. Conduct a site survey. Prior to choosing a UPS, it is wise to complete a site survey. Doing so ensures that all power requirements have been taken into account prior to installation, as well as other considerations such as room layout, available space, temperature and humidity control. Once the assessment is complete, you will be better prepared to select the optimal UPS — as well as any supplemental equipment such as PDUs or surge suppressors — to meet your unique needs and environment.

Need help deciding on a UPS? Get a free site assessment!

Click above to get started or call 240.772.1710 for instant help.

3. Determine the ideal UPS for your environment. UPSs come in a wide variety of shapes and sizes, and there are numerous questions to ask when selecting the best model for your organization. For instance, how critical are the loads being protected? What is your desired runtime? How reliable is the incoming utility power? Do you expect significant load growth in the coming years? And perhaps most important, what would the effects be if your company were to endure unexpected downtime?

For some installations, a single UPS may provide sufficient protection, while other applications require redundancy. Scalable, modular systems can benefit organizations that anticipate future growth in load demand. Many times, a certified pre-owned UPS will provide lower total cost of ownership (TCO) than a brand new unit. A qualified partner can be especially valuable to assist you in determining precisely what you need in a power protection solution.

4. Install the system. Once the UPS model has been selected, subsequent project management and commissioning are key to a successful installation. Confirm with your partner the timeline for delivery, any risks associated with the project, and if a planned power outage is required during installation.  

5. Sign up for service. While most UPSs feature a standard factory warranty, the majority of policies don’t include routine preventive maintenance (PM). However, because regular checkups have been proven to be one of the most effective ways to avert UPS failure, a service plan is a crucial step to protecting your investment. Make sure you engage with a service provider that provides highly skilled technicians, prompt emergency response service, and a well-stocked warehouse to ensure quick access to replacement parts.

Installing a UPS solution goes a long way toward safeguarding your organization against potentially devastating downtime, equipment damage and data loss. To avoid snags along the way, make sure you form a solid game plan before you deploy a new solution.

Still have questions? Get a response immediately.

Click above to get started or call 240.772.1710 for instant help.


How Long Will A UPS Last?

When Aristotle articulated that, “The whole is greater than the sum of its parts,” he obviously wasn’t referring to uninterruptible power systems (UPSs) — but he could have been. The famous quote, which suggests that individual parts connected together to form one entity are more valuable than if the parts remained separate, can certainly be applied to backup power solutions. Yet ironically, when trying to determine the lifespan of a UPS, it is those individual parts that must be closely considered.

Just how long will the average UPS operate and when are you at risk for failure? It’s a common question whose answer depends on a number of different variables, including the batteries, fans and capacitors. While some UPS systems can last 15 or more years before needing to be replaced, these primary components are subject to failure far earlier. To avoid downtime or damage to critical equipment, make sure you understand the lifecycle and maintenance requirements of a UPS’s key components. A little knowledge of your UPS’s primary parts will go a long way toward extending its lifespan.

1. Batteries — The heart of any UPS system, batteries are electrochemical energy storage devices that convert chemical energy into the electrical energy UPSs use to operate. Because the chemicals deplete over time, even UPS batteries that are well cared for will still need to be replaced. Most batteries have an expected lifespan of three to five years under ambient conditions. However, they can fail much faster in environments such as those that exceed an ambient temperature of 77°F, or where recurrent power problems cause batteries to cycle frequently. Battery life can also be significantly reduced if an organization doesn’t engage in regular service and maintenance. To learn more about the factors that influence UPS battery life, please check out our earlier blog on this topic.

Need help deciding on a UPS? Get a free site assessment!

Click above to get started or call 240.772.1710 for instant help.

2. Fans —One of the few UPS components that is mechanical in nature, a fan will wear out over time and eventually need to be replaced, usually between seven and ten years . Like other components, a UPS fan’s lifespan can vary on factors that include temperature, humidity, particulates, clogged air filters and how much rated power capacity the UPS is operating under. Avoid fan failures with proactive replacements.

3. Capacitors —Responsible for smoothing and filtering voltage fluctuations, capacitors typically need to be replaced every seven to 10 years. However, under unfavorable circumstances, they may operate for a much shorter time. Don’t wait until your UPS capacitors reach the end of their rated service life to start preparing for their replacement. Instead, request replacement quotes when they approach seven years old to ensure you are prepared, and take the time to read service reports closely. If there are any impending signs of failure, take steps to replace the capacitors immediately. For more information on capacitors, please refer to our previous blog on this component.

While the sum of a UPS’s parts represents the key to its successful operation, it is the individual parts that will determine how long the unit will last. Understanding the life cycle of key components will help you better assess the longevity of your UPS. Sometimes other factors will influence the best time to upgrade your unit. In our next blog, we will explore several considerations when replacing your UPS solution.

Still have questions? Get a response immediately.

Click above to get started or call 240.772.1710 for instant help.

Capacitors, UPS

UPS Capacitor Replacement: When, Why, How? (Video)

While much attention has been given to the importance of regularly replacing uninterruptible power system (UPS) batteries, there is also a lesser-known, often-overlooked component that cannot be ignored: the capacitors. After batteries, capacitors rank among the most common UPS elements susceptible to failure. Proactive attention to these components can extend the life of the UPS system and optimize the protection of your critical equipment.

Unified Power is the largest independent provider of mission critical power services in the United States. From battery preventive maintenance to battery capacity testing, UPS preventive maintenance and more, we can service any of your needs. Have a specific question about your specific power needs? Learn about all the power protection services we offer.

1 2 3 6 7
show blocks helper

Filter by Brand

Filter by Configuration


Filter by Amps

Filter by Phase

Filter by Power Rating (kVA)

Filter by Voltage

Privacy Settings
We use cookies to enhance your experience while using our website. If you are using our Services via a browser you can restrict, block or remove cookies through your web browser settings. We also use content and scripts from third parties that may use tracking technologies. You can selectively provide your consent below to allow such third party embeds. For complete information about the cookies we use, data we collect and how we process them, please check our Privacy Policy
Consent to display content from Youtube
Consent to display content from Vimeo
Google Maps
Consent to display content from Google
Consent to display content from Spotify
Sound Cloud
Consent to display content from Sound
Quick Quote
Or call (240) 772-1710 for immediate help.
Quick Quote
Cart Overview