After reading much, and suffering from power drop-outs, I bought an MGE Pulsar Evolution 1100 rack. I wired it up to my mini, and powered it up.
I found that though the Mac would read the UPS data on power-up, it would not update the status, and seemed to be totally unaware whether the Mains, or the UPS was powering the Mac.
This was a surprise, as all the various advisors insisted that the OSX power management software was fully interfaced to UPSs, and no other software was needed, and indeed warned that UPS software packages would impair the OSX facility.
Further rooting disclosed that I am not the first, by a very long way, to have this problem. Apple is not interested. MGE has now been taken over by APC, and this model is not seriously supported any more.
In desperation, I tried various methods to get the status to update, starting from re-starting the computer, which worked, but is not practical, before trying disconnecting the USB link to the UPS, and reconnecting it.
This is a fiddle, but it does work.
The status is updated when the channel is restored.
The next step then is to devise an automatic system to do what I can achieve poking around in the dark back of my computer.
The channel is normally quiescent after about 5 seconds from power-up, or re-start, so disconnecting has no visible effect on the computer, other that the icon being removed from the top line display.
There is no panic that something has been improperly disconnected.
After re-connecting, after about 5 seconds, the icon is restored, and the new status is displayed.
It seems then that this can be the basis for forcing OSX to update the UPS data.
It is a disgrace that Apple refuses to acknowledge this software fault.
They wash their hands of the Mac Mini Core Duo, and are not interested in Snow Leopard.
I will build a machine to automatically interrupt the UPS USB channel for 1 second every 60 seconds, and report back exactly how to do it, unless of course someone else out there knows better.
Ok, I got the timer unit from Ebay, a little card, about 5cm x 4cm, with some push buttons, 4 digit led display, and a SPDT relay.
I also got a pair of DPDT, with 5v coils, and glued them into a QPDT assembly.
Using a male to female USB cable, cut in half, I installed the QPDT assembly, using the NC contacts to restore the continuity of the cable.
Using the timer relay, to power the coils of the QPDT relay assembly, of 1 second every minute, I broke ion the USB cable between the Mac Mini, and the UPS.
To save time and unnecessary abuse of the batteries, I set the trip capacity to 95%. That is, the computer will shut down in an orderly manner after 5% of power is used.
Placing the timer unit where it could be viewed, as well as the capacity remaining indicator on the monitor screen, I set up my phone to shoot MP4, showing the timer state and the battery state.
This is where you can find the movie, showing it working.
It actually finds the shutdown level on the second scan because I had already done a trial run, and the battery had not been fully recharged.
Here is the movie:
https://app.box.com/s/ezvquc4wb8an5tdonncvvej03dmgtprq
I found that though the Mac would read the UPS data on power-up, it would not update the status, and seemed to be totally unaware whether the Mains, or the UPS was powering the Mac.
This was a surprise, as all the various advisors insisted that the OSX power management software was fully interfaced to UPSs, and no other software was needed, and indeed warned that UPS software packages would impair the OSX facility.
Further rooting disclosed that I am not the first, by a very long way, to have this problem. Apple is not interested. MGE has now been taken over by APC, and this model is not seriously supported any more.
In desperation, I tried various methods to get the status to update, starting from re-starting the computer, which worked, but is not practical, before trying disconnecting the USB link to the UPS, and reconnecting it.
This is a fiddle, but it does work.
The status is updated when the channel is restored.
The next step then is to devise an automatic system to do what I can achieve poking around in the dark back of my computer.
The channel is normally quiescent after about 5 seconds from power-up, or re-start, so disconnecting has no visible effect on the computer, other that the icon being removed from the top line display.
There is no panic that something has been improperly disconnected.
After re-connecting, after about 5 seconds, the icon is restored, and the new status is displayed.
It seems then that this can be the basis for forcing OSX to update the UPS data.
It is a disgrace that Apple refuses to acknowledge this software fault.
They wash their hands of the Mac Mini Core Duo, and are not interested in Snow Leopard.
I will build a machine to automatically interrupt the UPS USB channel for 1 second every 60 seconds, and report back exactly how to do it, unless of course someone else out there knows better.
Ok, I got the timer unit from Ebay, a little card, about 5cm x 4cm, with some push buttons, 4 digit led display, and a SPDT relay.
I also got a pair of DPDT, with 5v coils, and glued them into a QPDT assembly.
Using a male to female USB cable, cut in half, I installed the QPDT assembly, using the NC contacts to restore the continuity of the cable.
Using the timer relay, to power the coils of the QPDT relay assembly, of 1 second every minute, I broke ion the USB cable between the Mac Mini, and the UPS.
To save time and unnecessary abuse of the batteries, I set the trip capacity to 95%. That is, the computer will shut down in an orderly manner after 5% of power is used.
Placing the timer unit where it could be viewed, as well as the capacity remaining indicator on the monitor screen, I set up my phone to shoot MP4, showing the timer state and the battery state.
This is where you can find the movie, showing it working.
It actually finds the shutdown level on the second scan because I had already done a trial run, and the battery had not been fully recharged.
Here is the movie:
https://app.box.com/s/ezvquc4wb8an5tdonncvvej03dmgtprq
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