yes and no. btw very creative users use a USV as DC-to-AC-converter or charge batteries (2x12V = 24V system voltage) with solar, it seems to work even without batteries installed in the APC USV for example to power a lower power washing machine

a well done high quality USV definately increases the likelyhood of the connected hardware to survive power surges and lows but direct or indirect lightning strike might overwhelm the protection components inside the USV or trigger a disconnect not fast enough (?)

it is recommended to disconnect router and PC during severe storms (unplug also data cables!)

but who will remember that? also in areas of frequent lightning strikes, this might be very cumbersame (unplug, replug, unplug, replug)

so what possibilities are there? (according to GPT-OSS 120B)

full house protection: (costly) Install a whole‑house surge protector at the service panel• Use metal‑oxide varistor (MOV) or gas‑tube protectors rated for lightning‑level transients• Consider lightning arrestors on incoming lines

what the user would need is: Online (double‑conversion) UPS with built‑in high‑capacity surge protector (≥ 20 kA) + point‑of‑use SPD

To achieve high-capacity surge protection, especially for sensitive or industrial applications, the most reliable approach is to combine an online double conversion UPS with dedicated surge protective devices (SPDs). These SPDs include:

  • Type 1 SPD installed at the service entrance to protect against high-energy surges from lightning.

  • Type 2 SPD installed at the UPS input to protect it from switching surges and utility transients.

  • Sometimes Type 3 SPD near sensitive loads for additional protection.

layered protection ensures both continuous power and robust surge suppression. Integrated surge protection in UPS units often uses metal oxide varistors (MOVs) that handle only minor surges (a few hundred joules), which is insufficient for high-capacity surge demands. So for environments with frequent or large surges, dedicated SPDs compliant with IEC 61643-11, rated for tens of kiloamperes of surge current and low residual voltage, should be used alongside the UPS.

In summary, an online double conversion UPS combined with high-capacity SPDs in a cascade setup provides the best solution for uninterrupted power and comprehensive surge protection for high-demand applications like data centers, healthcare, and industrial automation

Key points for optimal indirect lightning protection:

  • Use an online double conversion UPS for clean, stable power and basic built-in surge filtering.

  • Supplement it with high-capacity Type 1 SPDs (class I) at the main electrical service entrance to handle direct lightning currents.

  • Add Type 2 SPDs (class II) at the UPS input to protect against residual surges and switching surges.

  • Optionally include Type 3 SPDs (class III) near sensitive loads for fine protection.

  • Ensure equipotential bonding throughout the electrical system to avoid sparking from differences in potential.

  • Follow standards such as IEC 62305-4 for the zone concept and IEC 61643-11 for surge protection device classifications

(src, src of src)

for basic overall protection: which USV model from which vendor?

  • GPT-OSS 120B:
    • APC (Schneider Electric)
      • model Back‑UPS Pro 1500 VA (BR1500G)
      • Power rating 1500 VA / 865 W
      • Surge‑protection rating 13 kA (IEC 61643‑11 Class II)
      • Battery runtime (≈ 150 W load) ~ 12 min
  • perplexity.ai:
    • Tripp Lite 1000VA Smart Online UPS (model SU1000RTXLCD2U), known for reliable double-conversion power, extended run options, and rackmount design.
    • Vertiv Liebert GXT5 series (e.g., GXT5-2000LVRT2UXL), Energy Star certified with strong surge handling and colored LCD for monitoring.
    • Eaton 9PX series, offering advanced battery management (ABM), high efficiency, and flexible battery options including lithium-ion.
      • Among these, Eaton 9PX stands out for combining robust power conditioning, energy efficiency, and advanced battery life extension technology, making it a top recommendation for basic yet reliable overall UPS protection incorporating surge suppression capabilities. However, for full surge and indirect lightning protection, dedicated external SPDs should still be installed alongside the UPS.
    • CyberPower CP1500PFCLCD, a popular model with high power factor and sine wave output suitable for sensitive electronics.
    • Maruson 1000VA Online UPS, a cost-effective double-conversion backup solution.
  • what else was found:

also very important question: which ones have good gnu linux debian support? (trigger proper OS shutdown after x min of power failure)

in case of a power failure, it would be optimal for a software to be running on PC or workstation or server (or any device that uses filesystems) to display an alert with a countdown, after which the device automatically starts a /scripts/proper-shutdown.sh script, which then should power down the filesystem-using-device.

but then filesystems and databases should be so robust as to handle unproper shutdowns (most are but not all).

  • APC
    • model: Back‑UPS Pro 1500 VA (BR1500G)
      • apcupsd
      • shutdown: apcupsd daemon (configurable UPSDELAY for minutes)
        • Very mature driver; easy to configure SHUTDOWNCMD.
    • model: Smart‑UPS 1500 VA (SMT1500C)
      • NUT (usbhid-ups) – also supported by apcupsd (limited)
      • nut (upsmon) + systemd integration
        • Higher‑end, but still cheap; NUT provides fine‑grained alerts.
  • CyberPower
    • model: CP1500PFCLCD
      • NUT (usbhid-ups)
      • nut (upsmon) – can call /sbin/shutdown -h now after delay
      • USB HID interface; works reliably on Debian 12+.
  • Eaton
    • model: 5S 1500VA (5S1500LCD)
      • NUT (usbhid-ups)
      • nut + systemd ExecStopPost for graceful shutdown
      • Good build quality; HID‑compliant
  • Tripp Lite
    • model: SMART1500LCD
    • Simple LCD, HID protocol

WARNING! the software part is UNTESTED maybe GPT-OSS 120B made up something X-D (any vendor that wants to send this user a USV for testing with GNU Linux Debian? 😀 no?)

apcupsd:


su - root; # become root
apt update && install apcupsd
vim  /etc/apcupsd/apcupsd.conf

UPSCABLE usb
UPSTYPE usb
DEVICE ONBATTERYDELAY 5 # seconds before “on battery” state is reported
BATTERYLEVEL 20 # % remaining before shutdown starts
MINUTES 5 # shut down after 5 min on battery
SHUTDOWNCMD "/sbin/shutdown -h now"

systemctl enable apcupsd
systemctl start apcupsd

## UPSes with solid Debian‑compatible shutdown support

### How to set up automatic shutdown (example with `apcupsd`)

1. **Install the daemon**

“`bash
sudo apt-get update
sudo apt-get install apcupsd
“`

2. **Edit `/etc/apcupsd/apcupsd.conf`**

“`conf
UPSCABLE usb
UPSTYPE usb
DEVICE
ONBATTERYDELAY 5 # seconds before “on battery” state is reported
BATTERYLEVEL 20 # % remaining before shutdown starts
MINUTES 5 # shut down after 5 min on battery
SHUTDOWNCMD “/sbin/shutdown -h now”
“`

3. **Enable and start the service**

“`bash
sudo systemctl enable apcupsd
sudo systemctl start apcupsd
“`

The daemon monitors the UPS via USB, and when the battery level falls below the configured threshold (or the runtime drops below `MINUTES`), it runs the `SHUTDOWNCMD`.

### Using **NUT** (Network UPS Tools)

1. **Install**

“`bash
sudo apt-get install nut nut-client
“`

2. **Configure `/etc/nut/ups.conf`** (example for a CyberPower UPS)

“`conf
[cyberpower]
driver = usbhid-ups
port = auto
desc = “CyberPower CP1500PFCLCD”
“`

3. **Set monitoring in `/etc/nut/upsmon.conf`**

“`conf
MONITOR cyberpower@localhost 1 upsmon secret password master
SHUTDOWNCMD “/sbin/shutdown -h now”
FINALDELAY 5
“`

4. **Enable services**

“`bash
sudo systemctl enable nut-driver.service nut-monitor.service
sudo systemctl start nut-driver.service nut-monitor.service
“`

Both `apcupsd` and `NUT` integrate with `systemd`, so the shutdown will be clean and respect the delay you set (e.g., 5 minutes). Choose the driver that matches your UPS brand; for APC the native `apcupsd` is simplest, while all other listed models work reliably with `NUT`.

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