The Eaton 3S 700 UPS powers critical devices when the grid doesn’t. Power surges are no longer a disaster.

The Eaton 3S 700 FR UPS (136 euros plus VAT) keeps your office’s critical infrastructure running when the power goes out. The device has a dual function: On the one hand, it is a UPS (Uninterruptible power supply)On the other hand, it protects devices from electric shocks.

Our test device has a rated output of 700 VA / 420 watts and is equipped with two rows of four sockets each. A practical symbol next to each line shows what to expect: One of the four sockets only offers protection against surges, the other four are also connected to a UPS battery. In the event of a power outage, the devices connected to it will continue to work for a while thanks to the built-in battery.

Handy size

Last year we started working with the Eaton 3S Mini UPS: a small and handy device that, in our opinion, is intended above all as part of a larger ecosystem. A small UPS doesn’t go far. The Eaton 3S 700 is not small, but it offers many useful and sometimes vital functions.

First, let’s look at surge protection. This ensures that power surges do not damage the devices connected to the UPS. This can save you a lot of headaches in the event of a lightning strike, for example. In such a case, electricity can also travel through the telecom cabling and still destroy devices. The Eaton 3S 700 also offers a solution here: two RJ11 ports on the front allow the cables to be routed through the surge protection. The eight available sockets offer the same protection.

The Eaton 3S 700 is of course primarily a UPS and one with a relatively large battery. You can use four sockets to connect devices that should not (immediately) fail in the event of a power outage. Think of a desktop computer, a server, or a router. We tested the device in an office environment and connected a Synology NAS along with the office router. We plugged some other devices into the surge protector, including a printer.

Installation and connections

The installation was quite easy. The UPS feels sturdy but is not overly heavy. The thing isn’t very small, but overall it’s relatively compact. We were able to place our copy anywhere, but Eaton also provides the necessary openings on the back to hang the device on the wall. An included brochure informs you, among other things, that you should not place the UPS on its side. There is only one thing you can do wrong: By default, the Eaton 3S 700 is switched off and the UPS sockets do not work. Press the front button to activate the UPS. A light at the top tells you when this was successful.

On the front of the UPS there is a USB Type B port next to the RJ11 ports. This is an antique connector that you may recognize from printer cables from back in the day. The Eaton 3S 700 can communicate with compatible devices via this port. We connect the UPS to a regular USB Type-A port on the Synology NAS using the USB cable.

Eaton is a big name in the UPS world and protecting a NAS with a UPS is a common scenario. Therefore, we are happy, but not surprised, that the Synology device recognizes the UPS immediately. In the server interface we see the battery charge level and the estimated number of autonomy seconds. Of course, what you see here depends on the device you are communicating with via the UPS.

Useful communication

The USB cable provides one of the most important functions of your UPS protected ecosystem. If the power outage lasts so long that the device’s battery runs out, our NAS will detect that the end is near and will automatically shut down in a safe manner. Different devices can serve as UPS servers and relay the same signal to other devices.

This is necessary because the Eaton 3S 700 has one offline UPS is. The device itself is not connected to the network and can only communicate via the USB-B port. Given the size of this device, we don’t think this is a major hurdle.

The UPS itself indicates what is happening via the front LED and a beep. When the battery is in use, the LED flashes green and an acoustic signal sounds every five seconds. This interval changes to two seconds when the battery is low. The message will then say to shut down your devices. The beep is clearly audible.

autonomy

How long the device’s battery lasts depends entirely on what you connect to the UPS. In demanding devices, the battery reaches a critical point after just a few minutes. If you choose a lightweight server and router, you can expect ten minutes or even more. In any case, you always have enough time to safely shut down sensitive devices. During our testing, we got more than twenty minutes of UPS charging with the NAS, router, and modem connected.

In the event of a short power outage, we can continue working on a network drive on the server via the local network, as the corresponding infrastructure is kept active by the UPS.

The surge protection works via a fuse, which you can also operate on the front of the device. We did not test this functionality for this review.

There’s one detail we haven’t mentioned yet: There are two USB Type-A ports on the top of the Eaton 3S 700 that deliver 2A of power. This allows you to (slowly) charge devices such as your smartphone. It is also possible to connect a device such as a Chromecast or a picture frame to the UPS.

Diploma

The Eaton 3S 700 is an ideal safety net for your critical office infrastructure. A handful of important devices, such as a small server, can be provided with backup power so that these devices can always be shut down safely. This prevents data loss and allows you to continue working even in the event of a short power outage. A practical extra are the four additional sockets with surge protection. Not only do you save on a power supply, but you also protect valuable material.

Communication via the USB port enables extended functionality, which is very useful for the intended use of this UPS. Online functionality is missing, but we don’t really miss it. In a larger office with multiple UPS units, something like this could theoretically be useful. The Eaton 3S 700 is also high quality, compact and easy to use. We recommend this device to any company with a NAS or employees who do important work at a desktop workstation.