BICKER_SER(8)

📦
version 2.8.5 · 12 versions
, in fedora 43, fedora 44

💖 BICKER_SER(8) — the NUT Manual, but make it a group chat 💖

okay bestie, sit down, hydrate, because we're talking about bicker_ser — the driver for Bicker DC UPS units that you talk to over a serial port. that's the manual name, BICKER_SER(8), and yes it's giving "section 8, admin commands" energy. periodt.

✨ NAME ✨

bicker_ser — the driver that lets you chat with a Bicker DC UPS over serial port connections. bestie it literally just talks to your UPS. slay.

🌸 SYNOPSIS 🌸

bicker_ser -h

bicker_ser -a UPS_NAME [OPTIONS]
📌 note, and it matters: this man page only documents the hardware-specific features of the bicker_ser driver. for the whole scoop on the core driver, go read nutupsdrv(8). iykyk.

🎀 SUPPORTED HARDWARE 🎀

bicker_ser supports all Bicker UPSes shipped with the PSZ-1053 extension module, such as UPSIC-1205, UPSIC-2403, DC2412-UPS and DC2412-UPS-LD. that's the whole list, no cap, and it's honestly a cute little lineup. 🦋

🌈 CABLING 🌈

the cable you need is a standard pin-to-pin serial cable with pins 2, 3 and 5 (on the DB9 connector) connected. that's it. three pins. you got this. 💅

💜 EXTRA ARGUMENTS 💜

this driver supports no extra arguments from ups.conf(5). literally none. not a single one. the vibe check came back empty and we respect that. 🙈

⭐ VARIABLES ⭐

depending on the type of your UPS unit, some of the following variables may be changed with upsrw(8). and here's the rule: if the driver can't read a variable from the UPS, it will not be made available. also, whenever it's not explicitly stated otherwise, any variable can be disabled — and when you disable it, the action it performs will not be executed. to disable a variable, set it to an empty value. noted? noted. 🫶

  • ups.delay.shutdown (in seconds, default disabled) — if you activate this and the UPS is in battery mode and the set time has expired, the output will be disabled, and the UPS and the energy storage will be disconnected. it just fully taps out.
  • ups.delay.start (in seconds, default disabled) — if you activate this and a restart condition switches the UPS output off and on again, the set time is the delay between switching on and off. the time should cause a defined off time so that capacities in the application can be discharged. think of it as a little nap window for your hardware. 😴
  • battery.charge.restart (in percent, default disabled) — if you activate this and the UPS is off or restarts, the UPS output will not be released until the energy storage device has the set charge state. in the meantime, the energy storage device is charged. main character energy: it refuses to show up until it's ready. 👑
  • battery.charge.low (in percent, default 20) — if you activate this and the UPS is in battery mode and the battery level drops below the set value, a shutdown command via relay event is signaled. 📉
  • experimental.output.current.low (in mA, default 200) — if you activate this and the UPS is in battery mode and the current drops below the set value, the output of the UPS will shut down and disconnect the energy storage to prevent self-discharge. it's protecting its own peace. 🧚
  • experimental.ups.delay.shutdown.signal (in seconds, default disabled) — if you activate this and the UPS is in battery mode and the set time has elapsed, a shutdown command via relay event is signaled.
  • experimental.ups.delay.shutdown.signal.masked (in seconds, default disabled) — if you activate this and the UPS is in battery mode and the signal at the IN-1 input is high and the set time has expired, a shutdown command via relay event is signaled. yes the name is long, we don't make the rules. 💀
  • experimental.battery.charge.low.empty (in percent, default 20) — this parameter stores the threshold value for the "Battery Empty" signal. currently this setting is only valid for relay signaling. Cannot be disabled. like, that's not optional, bestie.
  • experimental.ups.relay.mode (default 0x01) — this parameter controls the behavior of the relay in case of different events. Cannot be disabled. again: locked in. 🔒

available relay modes, in all their hexadecimal glory:

  • 0x01 — On power fail (normally closed)
  • 0x02 — On power fail (normally opened)
  • 0x03 — Shutdown impulse (1 second)
  • 0x04 — Battery low signal (normally closed)
  • 0x05 — Battery defect signal (normally closed)

🔥 INSTANT COMMANDS 🔥

  • shutdown.return — Turn off the load and return when power is back. iconic behaviour honestly.

😭 KNOWN ISSUES AND BUGS 😭

  • ups.delay.shutdown is not honored — although that delay is properly set when sending the shutdown command, it seems some UPS ignore it and use a fixed 2 seconds delay instead. the way that some UPS just do whatever they want... not them ignoring your carefully configured delay. 💀

💖 AUTHOR 💖

Nicola Fontana <ntd@entidi.it>

🦋 SEE ALSO 🦋

The core driver: 💅

Internet resources: 🌐

okay bestie that's the whole page, we ate and left no crumbs ✨ this was Network UPS Tools 2.8.5, dated 10/07/2026, and that's the BICKER_SER(8) page — go forth and serial-connect responsibly 🎀💜🌸

📦 where this page comes from