When the power goes out, the router or CCTV recorder may stop immediately, and even a short outage can cut the connection or stop recording at an important moment. That’s why many users look for a UPS for the router and cameras, but choosing one doesn’t depend on the VA number alone. The right capacity depends on the devices’ actual load, the number of cameras, the recorder’s consumption, battery condition and how long you want the system to keep running.
What does a UPS do in a router and camera network?
A UPS is a backup power source that usually contains a battery, a charger and an inverter circuit. When there’s power it runs the devices and charges the battery, and when the power goes out it switches to the battery so the connected devices keep working for a set time. The goal isn’t just keeping the screen on, but keeping the router, switch, recorder and cameras running within a load that doesn’t exceed the device’s capacity.
In a surveillance system, keeping the recorder alone running isn’t enough if the cameras or the switch powering them are off. So you should look at the whole system and decide what you want to keep running during an outage.
What’s the difference between VA and W?
A UPS is usually labelled in VA, such as 650VA, 1000VA or 1500VA, while device consumption is measured in watts (W). The two are related but not always equal. So you shouldn’t assume 1000VA automatically means you can run a 1000W load. The actual wattage capacity is set by the manufacturer for each model, and you should refer to the device’s own specs.
When comparing, look for the wattage limit as well as VA, then keep the actual load below the maximum with a comfortable margin. Running a UPS very close to its maximum capacity may shorten runtime and put more strain on the battery and device.
Start by listing the devices that will stay on the UPS
Before buying any UPS, write a list of the devices you need during an outage. In a simple home, the list may be just the router. In a surveillance system it may include a DVR or NVR, a set of cameras, a PoE switch, a router, and maybe a modem or fibre ONT. The screen isn’t always necessary if the goal is to keep recording, so it can be left off the UPS to reduce the load and extend runtime.
Don’t guess each device’s consumption if the power label or adapter is available. Check the label or the manufacturer’s specs. Some adapters list the maximum rather than the actual continuous consumption, so practical measurement with a power meter is more accurate when the required runtime matters.
How do you calculate the approximate load?
Add up the devices’ consumption in watts. If you have a recorder, cameras, a switch and a router, the total load is the sum of their consumption while running. Then add a margin instead of choosing a UPS that runs at the edge. This margin helps because some devices’ consumption varies, the switch load may rise as PoE devices are added, and the battery loses some efficiency with age.
What matters here is that calculating the load tells you whether the UPS can run the system, but it doesn’t give you the runtime on its own. Runtime also depends on battery energy, inverter efficiency, battery condition and temperature.
Why can’t runtime be known from VA alone?
This is one of the most common mistakes. Two 1500VA devices may not give the same runtime if their battery capacity, design efficiency or number of batteries differ. And the same UPS may run for a long time on a small router and much shorter on a full camera system.
So when you want, for example, several hours of runtime, ask for the runtime curve or battery specs, and don’t settle for the label “1500VA”. If the manufacturer provides a runtime table by load, it’s the best reference for comparison. If not, treat any runtime estimate as an approximate figure that needs testing on the actual system.
UPS for the router only
The router and modem usually draw much less than a full camera system, so you can get good runtime with a suitable device even if it isn’t large. But there’s an important point: keeping the router running doesn’t mean the internet continues if the provider’s equipment outside the home is also down. On fibre networks, make sure the ONT or the unit where the service enters the home is on backup power if it’s separate from the router.
If your goal is only to keep the internet and basic connectivity during an outage, don’t connect unnecessary devices to the same UPS. Every extra device reduces battery time.
UPS for security cameras
In surveillance systems you need a broader view. The recorder uses power, the internal hard drive uses power, the cameras need power, and the switch or power supply is part of the load. In a PoE system, the switch itself delivers power to the cameras, so its consumption depends partly on the number of cameras and each port’s power.
If you have a large number of cameras, don’t use the number of cameras alone to judge the UPS size. Ten cameras of one type may consume differently from ten of another, and an analogue system differs from an IP/PoE system. Add up the actual load or ask for a calculation based on the device models.
Should I connect the screen to the UPS?
If the main goal is to keep recording, you usually don’t need the screen during an outage. Leaving the screen off the UPS may save a large part of the load and extend how long the recorder, cameras and router stay on. You can turn the screen on from regular power when needed after the power returns, or use your phone to access the system if the network stays up.
Why does the waveform matter?
There are different UPS output designs; some give a waveform closer to a sine wave, while others use a simplified waveform on battery. Many modern electronic power supplies work with more than one type, but compatibility depends on the device itself. If you have sensitive equipment or special power supplies, check their specs and the UPS specs rather than assuming compatibility.
The battery is the factor that changes over time
Even if the UPS is suitable on the day you buy it, the battery is a consumable. High heat, the number of discharges, depth of discharge and battery age all affect performance. So you may notice after a while that the same system that ran for a certain time now shuts off sooner. This isn’t necessarily a VA capacity problem; the battery may need checking or replacing.
It’s useful to run a periodic test: safely cut the power and watch how long the system keeps running, and make sure the UPS doesn’t sound an overload alarm. Don’t wait for the first long outage to discover the battery no longer gives the required time.
Common mistakes when buying a UPS
- Relying on VA only: you need to know the wattage limit and battery capacity or runtime data.
- Connecting the screen and unnecessary devices: this reduces battery time with no benefit if the goal is to keep recording.
- Forgetting the switch or camera power supply: the recorder will keep running but may get no picture from the cameras.
- Choosing a capacity without a margin: it’s better not to run the UPS at its maximum continuously.
- Expecting a fixed runtime for years: battery performance declines with age and use.
- Neglecting to test the system after installation: the theoretical calculation matters, but real testing confirms the result.
How do you choose a UPS in practical steps?
- Decide which essential devices must run during a power cut.
- Add up their approximate consumption in watts from the specs or by measuring.
- Decide the runtime you actually need: minutes to protect recording, or hours to keep the system running.
- Choose a UPS whose wattage capacity exceeds the load with a suitable margin.
- Check the battery capacity and runtime data if available.
- After installation, test the system under the real load and record the runtime.
- Repeat the test periodically to monitor battery condition.
An example of the right thinking before buying
Instead of saying “I have eight cameras and want 1500VA”, gather more information: what’s the recorder model? Do the cameras run on PoE or a separate power supply? Do you want to run the router too? Is the screen necessary? And how many hours do you want the system to keep running? With this information you can determine a more realistic capacity and choose a battery that suits the required time.
This approach matters especially for shops and offices, because a small difference in load can change runtime significantly. And if the required time is very long, you may need a solution with larger batteries or a different backup power system instead of relying on a small desktop UPS.
Does a UPS also protect against power problems?
Protection functions vary from model to model. Some UPS devices offer regulation or protection against certain surges and dips, but you shouldn’t assume every device offers the same level of protection. Check the model’s official specs, especially if the power is unstable or the equipment is high-value.
Conclusion
Choosing a UPS for your router and cameras starts with the actual load and the required runtime, not the VA number alone. Count every device that needs to keep running, leave unnecessary devices off the load, check the wattage limit and battery capacity, then test the system after installation. If you’d like help determining the right capacity, have your device models, number of cameras, how they’re powered and the required runtime ready, so the calculation is closer to reality.
You can check Shaikh Alkar products or browse Articles for more practical guides on networks, surveillance systems and backup power.
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