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On Monday, 12 September 2022 06:57:58 BST Dale wrote: |
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> William Kenworthy wrote: |
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> > If your using nut, it has to be setup - and should be regularly tested |
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> > to make sure it works. |
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> > |
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> > BillK |
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> |
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> I think upsmon is part of nut. I keep forgetting that since the service |
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> is ups something. Thing is, I've never quite figured out how to test it |
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> without unplugging and running down the batteries. I do have everything |
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> configured and have ever since I built this puter. I did the same on |
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> previous puter and UPS. Pretty sure it will work. When power blinks |
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> etc, it does notice it and logs it in messages file. Also, the upsc |
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> command outputs the info correctly when run. |
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> |
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> I wish I could send a command to the UPS to fake a power failure, wait |
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> say one minute and then it tell puter to shutdown all on its own. If it |
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> does it correctly, it should work in the event of a actual power failure |
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> and not run down my batteries either. I try to keep the batteries |
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> topped off at all times since we do on occasion have some crazy driver |
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> not watching where he/she is going and hits a power pole. Doesn't do |
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> the pole any good and the car seems to not enjoy it either. :/ |
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> Sometimes the driver is no longer caring about it. |
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> |
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> I actually wish I had a much larger external battery. Thing is, I'm |
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> concerned about the charging bit. The charging section in a UPS isn't |
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> really that powerful since it mostly just keeps the batteries topped |
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> off. I have 7Amp/hr batteries and I think it takes like 7 or 8 hours to |
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> charge from almost dead. I'd guess it is at most a 1 to 1.5 amp |
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> charging circuit. |
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Many UPSs containing two batteries connected in series always end up with one |
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battery less charged than the other. This is because although the current |
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which flows through the circuit is the same, due to Ohm's Law the voltage |
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drops across each battery as the resistance decreases along the circuit. |
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Therefore the first battery never gets fully charged. The opposite happens |
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with a discharge cycle. |
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|
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Once every three months or every time I experience a noticeably prolonged |
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power cut, I shutdown the loads, take the UPS off line, disconnect the |
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batteries and top up each battery's charge with a car battery charger. Then I |
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replace them but make sure I reverse their positions. I have found this is |
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the best way to maximise their service life. |
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|
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I also use the car battery charger to top up single battery UPSs, but I only |
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do this twice a year. I have found the charge these single batteries need is |
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comparably shorter. |
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|
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> If you know of a command to test without running down batteries, I have |
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> a Cyberpower UPS and I'm certainly interested. It's only a decade or so |
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> old so has quite a few features. There may be a way to do this but I've |
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> yet to find it. |
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> |
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> Thanks. |
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> |
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> Dale |
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> |
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> :-) :-) |
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|
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Check the NUT command set and options, in particular upsmon. You'll probably |
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want to try issuing a 'forced shutdown' command 'upsmon -c fsd', which won't |
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wait for the batteries to discharge first, like it does with upssched. Before |
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you try this, best sync your disks first and remount them read only just in |
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case. |
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There may be some UPS specific test function too, this very much depends on |
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the UPS and driver. You can check what variables a UPS has and how to tweak |
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them to cause a shutdown by running 'upsrw -l', if any of the exposed UPS |
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variable are tweakable. |
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