Before you replace it open it up and reseat and retighten all the
connections (especially the battery terminals).
--
John Hasler
john@sugarbit.com
Elmwood, WI USA

--- PyGate Linux v1.5.16
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

At Sun, 14 Jun 2026 10:13:32 -0400 Eben King <eben@gmx.us> wrote:

On 6/14/26 10:07, John Hasler wrote:

Before you replace it open it up and reseat and retighten all the connections (especially the battery terminals).

Did that. I disconnected them all, checked the battery voltages (13.4
and something else reasonable), and checked the 60A fuse between them.
It's a weird fault, that it goes instantly from completely normal to bad.

Does it still work as a "dumb" UPS? If so, one possible temp solution is to
get an "old" dialup modem. Plug the modem's power brick into the *mains*, and connect the modem's TTY connection to a RS232 <=> USB adapter and then you can get powerd and have it monitor the ModemReady signal. The modem will assert ModemReady so long as it has power. ModemReady will drop when there is a power failure. (I suspect that this is probably not really a viable option. Back in the day, when PCs still had RS232 ports and dialup modems were common and cheap -- having an old 2400BAUD one lying about when you replaced it with a 9600 or 19.2K one would be common. These days are probably rare and PCs no longer have RS232 ports...)




--
Robert Heller -- Cell: 413-658-7953 GV: 978-633-5364
Deepwoods Software -- Custom Software Services
http://www.deepsoft.com/ -- Linux Administration Services
heller@deepsoft.com -- Webhosting Services


--- PyGate Linux v1.5.16
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Sun, Jun 14, 2026 at 12:42?PM Eben King <eben@gmx.us> wrote:

On 6/14/26 10:07, John Hasler wrote:

Before you replace it open it up and reseat and retighten all the connections (especially the battery terminals).

Did that. I disconnected them all, checked the battery voltages (13.4
and something else reasonable), and checked the 60A fuse between them.
It's a weird fault, that it goes instantly from completely normal to bad.

I don't think it goes from normal to bad. The smart UPSes estimate
battery health or life and then shutdown after annoying you with
beeping. I usually encounter it after replacing a bad battery with a
new one. The UPS acts as if the old battery is still installed.

Maybe reset the battery health or calibration that estimates health?
Use something like upsrw from <https://networkupstools.org/>. Or
search for "ups reset battery calibration linux".

Jeff

--- PyGate Linux v1.5.16
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

At Sun, 14 Jun 2026 14:48:50 -0400 Eben King <eben@gmx.us> wrote:

On 6/14/26 12:39, Robert Heller wrote:

At Sun, 14 Jun 2026 10:13:32 -0400 Eben King <eben@gmx.us> wrote:

On 6/14/26 10:07, John Hasler wrote:

Before you replace it open it up and reseat and retighten all the
connections (especially the battery terminals).

Did that. I disconnected them all, checked the battery voltages (13.4
and something else reasonable), and checked the 60A fuse between them.
It's a weird fault, that it goes instantly from completely normal to bad.

Does it still work as a "dumb" UPS?

You know, I haven't checked that. I would just need to unplug the USB
and reboot the UPS, correct?

If so, one possible temp solution is to
get an "old" dialup modem.

I actually do have two external modems, one 14.4 and one 33.6. I'm
fairly sure that at least one of them works. Just gotta find them...

Plug the modem's power brick into the *mains*, and
connect the modem's TTY connection to a RS232 <=USB adapter and then you can
get powerd and have it monitor the ModemReady signal.

Wait, I'm not clear on the connections.

UPS -> modem through RS-232

No, the modem is NOT plugged into the UPS, it is pluged into the wall (house/building mains). The modem is NOT on the UPS. The idea is that when there is a power failure, the modem goes off. While there is power to the modem it asserts its "ModemReady" (DSR, pin 6 on the 25-pin or pin 6 on the 9-pin connector: ioctl's TIOCMGET command, then bit TIOCM_DSR [man ioctl_tty(2)]).

then what does powerd do?

powerd is an (old) package that contains a general purpose deamon that can be configured to test something, such as a RS232 signal line and if the signal changes to a specificed state initiates a system shutdown (invokes "/sbin/shutdown -h <some time delay>"). I don't know if it still exists.

The modem will assert

ModemReady so long as it has power. ModemReady will drop when there is a power
failure. (I suspect that this is probably not really a viable option.

Yeah. If it just tells me when there's a power failure, the beeping
would tell me. Unless you're saying that powerd could kick off processes?

Yes. ACPUPSD does this.

These days are probably rare and PCs no longer have RS232 ports...)

I might have to use a USB -> RS232 adapter. The previous UPS had only regular serial and I used one of those, and when the boot procedure
initted the USB ports it sent something down the serial cable (BREAK?)
which caused the UPS to power off. Not ideal.

APC's "SmartUPS" communicate over the RS232 (older models) or USB (current models) a whole host of information about the UPS to the computer. The acpupsd package understands that communication and does various things, like broadcast messages about power failures and communication issues with the UPS, etc. The acpupsd daemon will also start a computer suchdown if the UPS indicates a
power failure. The acpupsd daemon will also act as a "server" to allow other computers on the UPS to know about the power failure so that "slave" acpupsd daemons can shutdown other computers that share the UPS.





--
Robert Heller -- Cell: 413-658-7953 GV: 978-633-5364
Deepwoods Software -- Custom Software Services
http://www.deepsoft.com/ -- Linux Administration Services
heller@deepsoft.com -- Webhosting Services


--- PyGate Linux v1.5.16
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Mon, 15 Jun 2026 14:35:24 -0400
Eben King <eben@gmx.us> wrote:

This time I ordered a surge suppressor too,
because that's how I think this one died. I live near Tampa.fl.us;
lotsa lightning here.

That's generally what lightning eats. Even if a suppressor appears to
be working after a strike, it can be damaged and not do its job next
time. I've had a phone answering machine confused after a strike but
came back on rebooting. A later strike killed it. I had an even earlier machine, one with a cassette for recording, killed on the first one.

We are much more likely to see lightning down the phone line than on the
mains. Not for much longer of course, the copper is going this year or
next.

--
Joe

--- PyGate Linux v1.5.16
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)