4 ms·

I have one of these APC Back-UPS 900 (BR900GI) here, and they work perfectly. Fully supported under apcupsd, that device has saved my bacon quite a few times. T

I have one of these APC Back-UPS 900 (BR900GI) here, and they work perfectly. Fully supported under apcupsd, that device has saved my bacon quite a few times. The only thing is that you MUST use the USB cable they provide.

throwawaaarrgh 3y ago
Doesn't that kind of prove they're messed up, if no other USB cable works?
- rincebrain 3y ago
  APC doing horrible things with "standard" cables isn't new, though - they used a nonstandard null modem serial cable back in the day, such that if you tried to connect to the UPS using a standard null modem cable, it'd trigger shutting off the UPS. This isn't to say it's good, just that it's not new.
  - extraduder_ire 3y ago
    Mine has a usb-A to rj45 cable with a ferrite bead on it, as far as I can tell it just wires the four USB wires (no ground) to the pins with spaces in between. I have never understood why they do this. It works perfectly with apcupsd though, even showing up in my desktop power settings as a UPS.
    - mrlonglong 3y ago
      This, 100%.
    - mynameisvlad 3y ago
      They might be repurposing the same chassis for both USB and Ethernet-based UPSes.
      - yanellena 3y ago
        Usually the APC UPS's with a network connection have a separate slot in card which has a network connection and an additional serial connection on it.
  - hackmiester 3y ago
    The pro series literally still has this exact connector today, with the same behavior.
    - fuzzfactor 3y ago
      APC was the only UPS company to have their device drivers natively included with Windows 95. That was before USB was available so they used regular COM port communication, I'm not surprised with that early foothold there was no reason to change and sufficient force to continue ever since. At the time it seemed like the un-necessarily non-standard RS-232 cable was just to create a "profit center" from the cables themselves, along with the non-standard replacement batteries. They sure would have been a lot quicker to market and had lower up-front engineering costs if they had used standard batteries from the beginning. It's good to recognize early when excessively high TCO is the primary feature around which a product (or company) is designed. There can be significant PR effort from the beginning to divert any perception of anti-consumer attitude. Lots of stealth can be involved to muddy the comparison with alternatives which offer normal TCO or well-engineered low-target TCO.
  - ronniefalcon 3y ago
    sysadmin right of passage #4
    - unwind 3y ago
      It's rite of passage [1], apologies if that was a typo or auto-correct etc. [1]: https://en.m.wikipedia.org/wiki/Rite_of_passage https://en.m.wikipedia.org/wiki/Rite_of_passage
      - ronniefalcon 3y ago
        are you a bot or do you do this in your spare time?
  - soneil 3y ago
    That's always drove me nuts because the underlying issue is a great idea, frustrated by its implementation. The serial port serves dual-purpose. Along-side the obvious serial, you can also provide some inputs by grounding certain pins, and some outputs by sinking current from others. This has got me through some unorthodox integrations by having the UPS signal that it's on battery by having these "simple signals" close a contact/relay on the load. It's not quite a full suite of dry contacts, but it's pretty serviceable. The problem is that 9 pins doesn't leave many spare, so to achieve this they've repurposed some. I really wish they'd implemented this as an alternate mode so you'd, for example short tx to rx to change the behaviour - instead of having the 'alternate behaviour' sitting on standard DTR/RTS pins. Getting industrial interfaces at SOHO prices was awesome. The unintended consequences .. less so.
  - csnover 3y ago
    It’s baffling. When APC first added native USB support to their Smart-UPS series, they chose a standard USB-B port. When they introduced “SmartConnect” a few years ago, this port was replaced by a USB-A port which requires a non-compliant USB-A male-to-male cable for monitoring. The only ‘good’ reason I can think of for this change is that someone realised that these new cloud-connected UPSes would be easily bricked by some bad firmware update (since apparently that’s a feature now), and wanted to use USB thumb drives as a recovery mechanism, but I have no idea. I think even though they have a built-in Ethernet port now, one still needs to buy their network management card for non-cloud remote management, so it could just as easily be another attempt at some weird vendor lock-in.
- rcxdude 3y ago
  The connector on the back is essentially a non-standard serial connector, and the USB cable is a USB-serial adaptor. You can probably make another work, but only by making an adaptor cable yourself. They have some models where the USB-serial adaptor is integrated into the unit, which is generally a bit easier to use and a more typical approach. (Generally, such a protocol is a better option from a compatibility point of view: it's usually fairly easy to reverse engineer. It would be interesting to sniff what the windows software is doing to work out what protocol or behaviour difference is responsible)
  - consp 3y ago
    The fun part is that there are at least two different, non standard, DB9 serial configurations.
    - ssl-3 3y ago
      The more-fun part is that using the wrong one can instruct an APC UPS to shut down immediately. (I'm not convinced that anyone has ever been behind the wheel of the ship that is called APC.)
    - mr_person 3y ago
      I have lost 3 different usb-to-serial adapters to an old server room APC, probably for this reason
- deleted 3y ago
  [deleted]
tempest_ 3y ago
I just bought batteries for a 20 year old UPS, still chugs along, network interface is base 10!
- StillBored 3y ago
  I had a 20 year old APC start misbehaving on me a few months back, and new batteries didn't fix it. After messing up the repair on the first one, a second one started doing the exact same thing, and I immediately took it apart and, now an expert on how not to fix them and what the root cause was, I swapped every cap on the board that my ESR meter claimed was bad. It's now back in operation, and while I was testing it, I realized it's so inefficient that about 10% of its max rating is just going up in heat. The replacement for the first one, I assumed, would be much more efficient, and it is, but it's still dumping about 7% of its energy into heating the transformer. OTOH, the older UPS behaves much better with apcupsd, going so far as giving me the firmware versions, battery replacement times, better power monitoring/etc. While the new one works its missing most of what the older UPS could do (although its not a APC). So, i'm sorta on the fence about just using "backup generators" from Amazon/etc because one of the ones I have has about 5x the capacity of the new UPS and seems to be able to switch without the computer plugging into it having an issue. Plus, its power waste is less than 1%.
  - tempest_ 3y ago
    It is an Smart-UPS 2200 manufactured 10/16/01 The batteries are definitely worth more than the unit is at this point. A backup generator for me is not an option but this is mostly just to keep internet and a couple machines going in the event of a power failure. One day maybe the used lithium ion one will pop up and I will swap it out.
    - StillBored 3y ago
      If you don't actually need the ~2 kw peak power output, there are a bunch of off brand 100-200W power stations with 50-150Wh batteries that aren't much more new than a new battery load for that old UPS (ex: random hit, flashfish 40800mAh Solar Generator - $129, powkey 200W $100). Although the Wh ratings are suspect on may of them, and they aren't online/line-ineractive (which is why they are more efficient) so you lose the power conditioning since they are effectively offline UPS's. I see people dumping old jackery, ecoflow, models for 1/3 of retail on craigslist/etc somewhat regularly although those tend to be larger models. Its a bit of a mystery to me why some of them aren't advertised as having UPS functions if they have fast switch times, which many of them do since they don't have physical relays. My old line interactive UPSs are all physical relays which click when they switch over, the assumption is that the energy in the transformer is sufficient to cover the switching time, but of course they do brown out a bit when near their current limits.
iforgotpassword 3y ago
I've had an AMD based home server a decade ago. Connected an HP printer, and it would frequently cause disconnect and reconnect events in dmesg, sometimes ending up in some error state when Linux would just give up trying to identify the device. After trying different ports and cables I eventually, out of desperation, threw in an unpowered old USB 2.0 hub and lo and behold, the connection to the printer was rock solid.

throwawaaarrgh 3y ago

Doesn't that kind of prove they're messed up, if no other USB cable works?

rincebrain 3y ago
APC doing horrible things with "standard" cables isn't new, though - they used a nonstandard null modem serial cable back in the day, such that if you tried to connect to the UPS using a standard null modem cable, it'd trigger shutting off the UPS. This isn't to say it's good, just that it's not new.
- extraduder_ire 3y ago
  Mine has a usb-A to rj45 cable with a ferrite bead on it, as far as I can tell it just wires the four USB wires (no ground) to the pins with spaces in between. I have never understood why they do this. It works perfectly with apcupsd though, even showing up in my desktop power settings as a UPS.
  - mrlonglong 3y ago
    This, 100%.
  - mynameisvlad 3y ago
    They might be repurposing the same chassis for both USB and Ethernet-based UPSes.
    - yanellena 3y ago
      Usually the APC UPS's with a network connection have a separate slot in card which has a network connection and an additional serial connection on it.
- hackmiester 3y ago
  The pro series literally still has this exact connector today, with the same behavior.
  - fuzzfactor 3y ago
    APC was the only UPS company to have their device drivers natively included with Windows 95. That was before USB was available so they used regular COM port communication, I'm not surprised with that early foothold there was no reason to change and sufficient force to continue ever since. At the time it seemed like the un-necessarily non-standard RS-232 cable was just to create a "profit center" from the cables themselves, along with the non-standard replacement batteries. They sure would have been a lot quicker to market and had lower up-front engineering costs if they had used standard batteries from the beginning. It's good to recognize early when excessively high TCO is the primary feature around which a product (or company) is designed. There can be significant PR effort from the beginning to divert any perception of anti-consumer attitude. Lots of stealth can be involved to muddy the comparison with alternatives which offer normal TCO or well-engineered low-target TCO.
- ronniefalcon 3y ago
  sysadmin right of passage #4
  - unwind 3y ago
    It's rite of passage [1], apologies if that was a typo or auto-correct etc. [1]: https://en.m.wikipedia.org/wiki/Rite_of_passage https://en.m.wikipedia.org/wiki/Rite_of_passage
    - ronniefalcon 3y ago
      are you a bot or do you do this in your spare time?
- soneil 3y ago
  That's always drove me nuts because the underlying issue is a great idea, frustrated by its implementation. The serial port serves dual-purpose. Along-side the obvious serial, you can also provide some inputs by grounding certain pins, and some outputs by sinking current from others. This has got me through some unorthodox integrations by having the UPS signal that it's on battery by having these "simple signals" close a contact/relay on the load. It's not quite a full suite of dry contacts, but it's pretty serviceable. The problem is that 9 pins doesn't leave many spare, so to achieve this they've repurposed some. I really wish they'd implemented this as an alternate mode so you'd, for example short tx to rx to change the behaviour - instead of having the 'alternate behaviour' sitting on standard DTR/RTS pins. Getting industrial interfaces at SOHO prices was awesome. The unintended consequences .. less so.
- csnover 3y ago
  It’s baffling. When APC first added native USB support to their Smart-UPS series, they chose a standard USB-B port. When they introduced “SmartConnect” a few years ago, this port was replaced by a USB-A port which requires a non-compliant USB-A male-to-male cable for monitoring. The only ‘good’ reason I can think of for this change is that someone realised that these new cloud-connected UPSes would be easily bricked by some bad firmware update (since apparently that’s a feature now), and wanted to use USB thumb drives as a recovery mechanism, but I have no idea. I think even though they have a built-in Ethernet port now, one still needs to buy their network management card for non-cloud remote management, so it could just as easily be another attempt at some weird vendor lock-in.
rcxdude 3y ago
The connector on the back is essentially a non-standard serial connector, and the USB cable is a USB-serial adaptor. You can probably make another work, but only by making an adaptor cable yourself. They have some models where the USB-serial adaptor is integrated into the unit, which is generally a bit easier to use and a more typical approach. (Generally, such a protocol is a better option from a compatibility point of view: it's usually fairly easy to reverse engineer. It would be interesting to sniff what the windows software is doing to work out what protocol or behaviour difference is responsible)
- consp 3y ago
  The fun part is that there are at least two different, non standard, DB9 serial configurations.
  - ssl-3 3y ago
    The more-fun part is that using the wrong one can instruct an APC UPS to shut down immediately. (I'm not convinced that anyone has ever been behind the wheel of the ship that is called APC.)
  - mr_person 3y ago
    I have lost 3 different usb-to-serial adapters to an old server room APC, probably for this reason
deleted 3y ago
[deleted]

tempest_ 3y ago

I just bought batteries for a 20 year old UPS, still chugs along, network interface is base 10!

StillBored 3y ago
I had a 20 year old APC start misbehaving on me a few months back, and new batteries didn't fix it. After messing up the repair on the first one, a second one started doing the exact same thing, and I immediately took it apart and, now an expert on how not to fix them and what the root cause was, I swapped every cap on the board that my ESR meter claimed was bad. It's now back in operation, and while I was testing it, I realized it's so inefficient that about 10% of its max rating is just going up in heat. The replacement for the first one, I assumed, would be much more efficient, and it is, but it's still dumping about 7% of its energy into heating the transformer. OTOH, the older UPS behaves much better with apcupsd, going so far as giving me the firmware versions, battery replacement times, better power monitoring/etc. While the new one works its missing most of what the older UPS could do (although its not a APC). So, i'm sorta on the fence about just using "backup generators" from Amazon/etc because one of the ones I have has about 5x the capacity of the new UPS and seems to be able to switch without the computer plugging into it having an issue. Plus, its power waste is less than 1%.
- tempest_ 3y ago
  It is an Smart-UPS 2200 manufactured 10/16/01 The batteries are definitely worth more than the unit is at this point. A backup generator for me is not an option but this is mostly just to keep internet and a couple machines going in the event of a power failure. One day maybe the used lithium ion one will pop up and I will swap it out.
  - StillBored 3y ago
    If you don't actually need the ~2 kw peak power output, there are a bunch of off brand 100-200W power stations with 50-150Wh batteries that aren't much more new than a new battery load for that old UPS (ex: random hit, flashfish 40800mAh Solar Generator - $129, powkey 200W $100). Although the Wh ratings are suspect on may of them, and they aren't online/line-ineractive (which is why they are more efficient) so you lose the power conditioning since they are effectively offline UPS's. I see people dumping old jackery, ecoflow, models for 1/3 of retail on craigslist/etc somewhat regularly although those tend to be larger models. Its a bit of a mystery to me why some of them aren't advertised as having UPS functions if they have fast switch times, which many of them do since they don't have physical relays. My old line interactive UPSs are all physical relays which click when they switch over, the assumption is that the energy in the transformer is sufficient to cover the switching time, but of course they do brown out a bit when near their current limits.

iforgotpassword 3y ago

I've had an AMD based home server a decade ago. Connected an HP printer, and it would frequently cause disconnect and reconnect events in dmesg, sometimes ending up in some error state when Linux would just give up trying to identify the device. After trying different ports and cables I eventually, out of desperation, threw in an unpowered old USB 2.0 hub and lo and behold, the connection to the printer was rock solid.