BX1500G Misbehavior When Power Is Restored

[timj_apc]

This was originally posted on APC forums on 4/22/2011

---

I have the BX1500G and am running Windows 7 x64 SP1 with Powerchute Personal 3.0 (PP3). I just tested what happens when power goes out while the computer is in sleep mode, and this is what I found:

1. I manually sleep the computer.
2. I manually trip the breaker to the room. (Getting to the wall outlet would require me to pull my desk out, which isn't easy.)
3. The computer has resumed from sleep in the 10 sec or so it takes me to get back to the room.
4. The computer hibernates after 2 minutes per configuration in PP3.
5. I reset the breaker.
6. When I get back, the computer has restarted, despite the BIOS option "Restore on AC Power Loss" being set to "Power Off" and all other wake options being disabled.
7. I use TrueCrypt (TC), so I just wait for a while with the computer at the TC password prompt, which appears right after the BIOS loads, before Windows begins to load. The UPS continues to supply battery power for about a minute.
8. Then the UPS shuts off and turns back on within about a second, transitioning to wall power in the process. This causes the PC to turn off, as well as other connected equipment, such as my cable box, router, cable modem, etc.
9. The PC restarts again, and after I enter the TC password, Windows resumes from hibernation.

This is just horribly wrong, and I confirmed it's real by doing it twice. Items (6), (8), and (9) should not be happening, and I can't explain the extended time on battery power after wall power has been restored described in (7). The UPS passes self-test, and the load is around 25%, with remaining runtime of 20 minutes. I guess if I wasn't using TrueCrypt or had entered the password and allowed Windows to boot, the UPS would have turned off and then back on while Windows was loading or I was using Windows, defeating the purpose of the UPS. It makes no sense at all.

I also tried it with the PC off, and with it on but sitting at the TC prompt. None of this nonsense happened. Of course, the UPS didn't power the PC down, but it resumed wall power instantly, without the UPS turning off and then back on.

Is this a known problem? What to do?

Message was edited by: timj

Message was edited by: timj

[timj_apc]

This was originally posted on APC forums on 4/23/2011

---

To test whether the BIOS "Restore on AC Power Loss" setting is working correctly, I booted to the TC password prompt, and then I unplugged the PC from the UPS. I waited 30 sec and plugged the PC back in, and it did not restart. I also booted into Windows and manually hibernated the system. After it shut down, I unplugged the PC from the UPS, waited 30 sec, and plugged it back in. The PC did not restart then, either. So that's working right.

I can only conclude that in the Windows scenario described in my first message, PP3 is somehow programming the UPS to send a USB signal to restart the PC when power is restored, which is just completely unwanted and improper. I don't see any other explanation for why the PC is restarting.

[BillP]

This reply was originally posted by Angela on APC forums on 4/25/2011

---

this might have to do with the shutdown timeline for these units:


Shutdown time line, software not installed:*

1. UPS goes to battery, the on battery beep sounds

2. The UPS will sound the on battery beep until it reaches the last few minutes of run time. The length of time depends on the load and how old the battery is.

3. When the unit reaches the last few minutes of battery life it will then sound its low battery alarm.

4. Just before the battery is completely exhausted the ups will turn itself off.

5. If the UPS went to battery due to a brown out the unit at this point will be in LVSM until the voltage becomes acceptable again.

PowerChute Personal Edition default shutdown time line:*

1. UPS goes to battery and PCPE starts its preserve battery power counter.

2. When the counter expires it sends a command to the UPS to start counting its turn off delay and then commands the OS to shutdown.

+3. The operating system shuts down and the UPS continues to count its turn off delay. (Once the UPS finishes counting its turn off delay it will reboot and nothing can stop this from happening.)+

4. The UPS cuts power to the outlets then rechecks to see if the incoming power is acceptable. If it is not it waits there until power returns.

5. If the UPS went to battery due to a brown out the unit at this point will be in low voltage sleep mode until the voltage becomes acceptable again.


i read the post quickly but this is what it sounded like to begin with.

[voidstar_apc]

This was originally posted on APC forums on 4/25/2011

---

It sounds like the problem here is that the computer restarted itself from hibernation before the UPS turned itself off and back on. That's odd--I'm curious why. Does it happen exactly when power is restored to the UPS? The up-side is that Truecrypt is nicely suppressing Windows from loading so at least there should be no adverse consequences.

[timj_apc]

This was originally posted on APC forums on 4/25/2011

---

voidstar wrote:
It sounds like the problem here is that the computer restarted itself from hibernation before the UPS turned itself off and back on. That's odd--I'm curious why. Does it happen exactly when power is restored to the UPS? The up-side is that Truecrypt is nicely suppressing Windows from loading so at least there should be no adverse consequences.

Yes, TrueCrypt is saving the Windows installation from any bad consequences due to the unwanted restarting because Windows doesn't get a chance to load thanks to the PC being stuck at the TC password prompt. However, it's still wrong for the UPS to restart the PC (twice!) and power off and restart the other connected equipment. I mean, it takes my cable box 10 minutes to recover, and if I had a DVR, it would interrupt any recording taking place. How the UPS behaves after causing the orderly shutdown of the PC doesn't make any sense to me, and it behaves completely differently and sanely when it does not cause the PC to hibernate. (Though I don't know how the UPS behaves when it shuts down due to running out of battery power - I didn't test that.)

Getting back to the orderly shutdown scenario, after wall power is restored, the computer restarts twice. The first time it restarts, after I reset the breaker, I don't know exactly when it happens, as it takes me 10 sec to get back to the room, but the PC is on when I get there, and since it takes the BIOS a few seconds to load, and I find it at the TrueCrypt prompt, it has to have restarted within the first couple of seconds. The second time, the PC restarts immediately after the UPS turns itself off and then back on. Note that as I described in my second message, the PC doesn't spontaneously restart after losing then regaining power. It can lose power while sitting at the TrueCrypt prompt or after being hibernated from Windows; either way, it stays off when power is restored. It must be the UPS that is causing it to restart, and I want it to stop!

[R2_apc]

This was originally posted on APC forums on 4/25/2011

---

Hi timj, a simple test we can try to see how the computer and UPS are interacting is to manually put the computer into hibernate mode. Once in hibernate mode, with the ups still online and on AC power, unplug the computer and replug it back into the UPS. From here we should be able tell if it is the BIOS giving up issues (as once the computer is in hibernate mode, the ups has no way to communicate with the computer). Hope this helps.

[timj_apc · Accepted solution]

This was originally posted on APC forums on 4/25/2011

---

R2 wrote:
Hi timj, a simple test we can try to see how the computer and UPS are interacting is to manually put the computer into hibernate mode. Once in hibernate mode, with the ups still online and on AC power, unplug the computer and replug it back into the UPS. From here we should be able tell if it is the BIOS giving up issues (as once the computer is in hibernate mode, the ups has no way to communicate with the computer). Hope this helps.

Please read my second message, where I described doing exactly that, and my third where I reiterated what happens.

ETA: Just to emphasize it for a third time, the computer does not restart in the manual hibernation scenario. As I stated earlier, for the "orderly shutdown scenario", when the computer has hibernated due to Powerchute, after wall power is restored, the UPS must be communicating with the PC over USB, which may still be powered even when the PC is off or hibernated, despite the fact that all the power-on triggers (keyboard and such) are disabled. There's nothing in the BIOS to control that, nor is there a motherboard jumper for it on my Asus P7P55D Pro. In any event, the bottom line is that the UPS has no business sending such a signal after the PC has been hibernated and "orderly shut down".

Message was edited by: timj