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betreger
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Message 70014 - Posted: 7 Jun 2016, 15:13:48 UTC

Today's outrage started at 8:11 PDT. Enjoy being outraged.
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msattler

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Message 70015 - Posted: 7 Jun 2016, 15:35:34 UTC

The kitties are suitably outraged.....

Meowgrowl.
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Message 70017 - Posted: 7 Jun 2016, 17:44:34 UTC - in response to Message 70016.  

Jeff's in early, what's the big deal??

The early bird gets the worm.......
But the kitties were never very fond of worms.

Meow.
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Message 70018 - Posted: 7 Jun 2016, 18:06:05 UTC

Winning after work..
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Cosmic_Ocean
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Message 70021 - Posted: 7 Jun 2016, 18:55:30 UTC

Re: the discussion about power surges and so forth...

Yes, here in the US, it is 120v 60Hz. Actually, I think we're officially 110 or 115v, but everyone just calls it 120. My UPS is reading 121 right now I've seen it as high as 128, but typically somewhere right around 124 is the norm. During the high-heat of the summer (mid-July through mid-September), I've seen the UPS read 101v before. I was pretty sure that was wrong, so I dug my multimeter out and stuck it in a wall socket.. it agreed with 101v.

I went to my neighbor across the street (on a different series of transformers than I am on--as witnessed when my side of the street goes dark, but they don't) and they were also showing 101v. I guess the hydro-electric power plant was having trouble keeping up with demand.

The problem with power going out or coming back on is that it doesn't do it very cleanly. Going out is usually because something bad happened and it does a chain-reaction over the course of about a quarter second and triggers some safeguard. The sudden loss of load causes the supply to spike until the supply is decreased accordingly. So in an area that has.. say.. 50,000 amps worth of load on it, when you suddenly lose 30,000 amps of load, the remaining area that still has power will certainly see a voltage spike.

Similarly, when the power comes back on to an area that went down, all the appliances and everything that needs power all kicks back on, introducing a lot of noise into the system, so instead of a smooth sine wave, you end up with a very jagged and deformed sine wave. It gets worse the more sudden load there is. These days, more and more appliances have a time-delay built-in where they will wait a few seconds before contributing to the load.

That sudden load when power comes back on will not only cause a voltage drop (brown-out), but will also alter the frequency in a way that instead of being a sine wave, it practically becomes a square wave, or a sawtooth, if not increasing or decreasing the frequency itself by +/- 2-10. Most devices can handle a change of frequency under normal circumstances, but dealing with that during a brown-out is typically what fries electronics these days.

(side-note: that is the same reason why when you are using a power tool with a motor in it, if you are using an extension cord, you shouldn't leave most of the cord still rolled-up, even if you only need a couple feet of it. The rolled-up cord will end up doing cross-talk and under the load of the motor, you can actually destroy the windings in the motor due to feeding it anywhere between half and double the frequency it was designed for. I've seen it happen.)

That's the reason why if you use a surge suppressor, you'll still lose electronics when the power comes back on, because it's not a voltage surge--it's the opposite of that, so the suppressor does nothing, because there is nothing to suppress. A UPS fixes that problem, because they are also line-conditioners, and they protect against brown-out and surge.
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Profile Gordon Lowe
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Message 70024 - Posted: 7 Jun 2016, 20:16:19 UTC - in response to Message 70021.  

Cosmic_Ocean, that was a very interesting and informative post. ~Especially about the extension cords.

We have a whole-house generator that starts up when voltage from the power company dips below a certain threshold, and it runs everything automatically until the power company gets things back to normal. The computers still usually switch themselves off, and the lights sometimes dim a little, but I'm guessing/hoping the generator action has some safeguards built-in.
The mind is a weird and mysterious place
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Message 70026 - Posted: 7 Jun 2016, 21:53:10 UTC

Quality generators (especially the kind that do whole-house and auto-switching) have loads of filtering/conditioning/shaping equipment in them. They produce a very clean sine wave. Lower-quality ones (like portable generators) are very noisy (electrically). I have an 1800-watt one that produces such a noisy signal that my UPS refuses to accept it as line voltage. I have a 6500-watt better-quality one (still with no fancy equipment on it) that the UPS will accept, but it will not do pass-through--it still runs the inverter to be a line conditioner, so it doesn't actually start re-charging the batteries, but it's better than nothing.

As for your computers switching-off when you change from mains to generator, that's what a UPS is actually intended for--to bridge the gap until the generator smooths out, or to provide enough time for a graceful shutdown.
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Profile Gordon Lowe
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Message 70027 - Posted: 7 Jun 2016, 21:58:20 UTC - in response to Message 70026.  

As for your computers switching-off when you change from mains to generator, that's what a UPS is actually intended for--to bridge the gap until the generator smooths out, or to provide enough time for a graceful shutdown.


So I should still probably get a UPS for each of my three computers?
The mind is a weird and mysterious place
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Cosmic_Ocean
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Message 70029 - Posted: 8 Jun 2016, 0:48:35 UTC - in response to Message 70027.  

As for your computers switching-off when you change from mains to generator, that's what a UPS is actually intended for--to bridge the gap until the generator smooths out, or to provide enough time for a graceful shutdown.


So I should still probably get a UPS for each of my three computers?

If you really want to. You'll have to size the UPSes accordingly, but if you don't have a multi-GPU cruncher, you can probably get away with one of those brick-type ones that are ~350VA (they look like a brick). They should hold a 300-watt machine for 2-4 minutes, which you'll only need a fraction of to wait for the generator to activate.
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Message 70030 - Posted: 8 Jun 2016, 7:51:18 UTC

That's the problem here.....
I simply have far too much kit online to afford the amount of UPS support to supply them.
I do have some power conditioning online for my modem, router, and monitor, but it did not seem to help this time.

Electricity can be a very strange beastie.
Normally supplied mains voltage is usually pretty predictable.
But when Mother Nature gets involved and starts injecting 'free will' electrons with unknown maximum potential into the system, things go haywire.
These little bits of loose cannon electrons seem to go where they please and do what they will.......

For example, how does a spike get through the 120vac to 12vac wall wort for the modem to destroy it, but leave the wall wort itself intact and functional?

How do those raging electrons get into a computer and take out a GPU whilst leaving it's PSU and everything else seemingly untouched?

How does any of this happen when I have very substantial whole house spike protection installed at the mains box? I mean, surge suppression, noise suppression, voltage gates, clamping diodes, and more ground rods driven than most apartment complexes.

I think it's the Langoliers....
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Jimbocous
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Message 70036 - Posted: 8 Jun 2016, 9:33:22 UTC - in response to Message 70030.  

That's the problem here.....
I simply have far too much kit online to afford the amount of UPS support to supply them.
I do have some power conditioning online for my modem, router, and monitor, but it did not seem to help this time.

Electricity can be a very strange beastie.

Yup.

For example, how does ...
How do ...
How does ...

It's magic! (PFM) Been doing electronics since forever, and that's still my fall-back.

As far as affordable UPS, guess it all comes down to how much back-up you want, and how many boxes you run.
I'm running 4 crunchers (you know the details, I think), and my TV, Stereo and a few other goodies like a lamp, routers and cable modem off a single 2200VA APC that I have a tad over $200 invested in, used off eBay. That does NOT count the batteries, which I reused from my 2000va that smoked. With a 48v string at 73ah, I get about 45 minutes run time on the 2200 at 80% load.

There's several different approaches you can take to UPS:

1) Just enough UPS to keep things safe until the CPU can be shut down (cheap),
2) Enough to get through most outages (moderate), or
3) Batteries 'till the cows come home ($$$$).

Probably not telling you much you don't know, though I'm glad to offer advice and suggestions (for anyone interested). DC power systems were my life for quite a few years, so UPS advice comes easy ... Suppression systems and the like are all fine and great, but we always used to say the best protection out there is a decent set of batteries, and that's still true.
Certainly no shortage of pretty good size UPSs to be had used on eBay, and the smart money buys them without batteries to save shipping costs that will exceed the price of a trip to Batteries Plus for new. And, BTW, there are some pretty decent deals on batteries at eBay and Azon, even counting shipping.
Ridiculous how cheap a lot of this all is. I decided I wanted web access to that 2200 UPS, an old card to do that cost a whopping $20 including shipping.

Later, ...
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msattler

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Message 70037 - Posted: 8 Jun 2016, 9:40:31 UTC

I have to be toast for the night, otherewie I shall be toaste in morning.

\meow for now.
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Message 70038 - Posted: 8 Jun 2016, 9:52:57 UTC - in response to Message 70037.  

I have to be toast for the night, otherewie I shall be toaste in morning.

\meow for now.

+1
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Profile Jord
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Message 70066 - Posted: 8 Jun 2016, 23:27:19 UTC

Mark is on a 2 month vacation, starting today.
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Cosmic_Ocean
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Message 70069 - Posted: 9 Jun 2016, 5:58:06 UTC - in response to Message 70036.  

[...]Certainly no shortage of pretty good size UPSs to be had used on eBay, and the smart money buys them without batteries to save shipping costs that will exceed the price of a trip to Batteries Plus for new. And, BTW, there are some pretty decent deals on batteries at eBay and Azon, even counting shipping.
Ridiculous how cheap a lot of this all is. I decided I wanted web access to that 2200 UPS, an old card to do that cost a whopping $20 including shipping.

Later, ...

I agree with this. About 7 years ago (wow.. has it really been THAT long..? whoa) when I was working at my local technical/vocational college, I was tasked with digging through the server closet for the entire IT-course department as well as all the racks in the Linux and Cisco classrooms and finding equipment that doesn't work, figure out why it doesn't work, and then decide if it should be fixed or written-off.

At the end of my week-long investigation, I came across about 15 servers that were.. easily approaching 10 years old (at that point in time): single-core, two CPU socket 4U Xeons. I don't even want to know what the power consumption of those behemoths were, but the 4x36gb 15k RPM SCSI RAID-10 was the only thing that might have been worthwhile for migrating into a more modern machine.

Skipping past all of the other stuff that got put into a massive pile in an unused classroom for campus IT dept to pick up and remove from inventory and write-off.. I had two Tripp-Lite 1400VA 4U rackmount UPSes, and three 3000VA APC 4U UPSes--two of which were 120vAC 30A (with a twist-lock plug), and one was 240vAC, with a twist-lock as well. All five were absolutely dead as a doornail, and after being plugged-in for three days, a multi-meter on the batteries was still reading near-zero.

There were no inventory tags on them. So I contacted the campus IT dept. and gave them the make, model, and serial to see if they had any records of them. I got an email 30 minutes later saying none of them showed up in the system anywhere--not even in the "previously discarded" database table.

I asked my boss if he wanted me to just dumpster them, and he said I couldn't because of "hazmat" (lead in the batteries). So I removed all the batteries (8 each in the 3000VA units, 3 each in the Tripp-Lite units) and put them all in the trunk of my car and took them to the scrap metal recycler on the way home and got 28 cents/pound for the lead in them.

Came back the next day, asked if they could go in the dumpster now that the hazmat has been taken care of.. he decided that we should get battery kits for them. But the budget was limited, so he could only afford one of the 3000VA units at the time. I recommended the site that I use out of Texas (can get the 8 batteries for a 3000VA unit for under US$200 shipped).

After a month of the stripped units sitting on the floor in my office, he told me that I could just take the two Tripp-Lites home. Which I did. Got batteries for those (went with 12AH instead of the 7AH that came out of them) and they served me quite well.

I really wanted a 3000VA unit though, so I looked on ebay, and a battery-less chassis can be had for under $250, and then the battery kit for ~$200, and you have a 3000VA UPS for under $500--when the retail list price on an APC 3000VA unit is..*looks it up*..Between $1100-1600 brand new these days... but 7 years ago when I was looking this up.. a 3000VA unit was about $3500. But even today, that's still a good deal.

I have, in total, 6300VA in 4 UPSes (1300, 1400x2, 2200) that I didn't pay for at all, except to put new batteries in them. They were all given to me. Fine by me.


tl;dr.. ebay is totally the way to go to get UPS carcasses. And old-ish servers for cheap.
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Message 70070 - Posted: 9 Jun 2016, 6:18:32 UTC - in response to Message 70069.  

I agree with this. About 7 years ago ... I was tasked with digging through the server closet for the entire IT-course department as well as all the racks in the Linux and Cisco classrooms and finding equipment that doesn't work, figure out why it doesn't work, and then decide if it should be fixed or written-off.

I hear you. I really do miss working in that world; the "junk" I used to pull out of the dumpster pile was amazing. I still have a case of 1 gig SCSI HDs down in the basement. Impressive for their time, now just boat anchors ...
Can't decide if I want to go for another UPS right now or not. There's another 2200XL on Ebay right now for under $200 including shipping. But I don't really need it .... Sigh
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Message 70073 - Posted: 9 Jun 2016, 7:04:24 UTC

Since we're jawing about UPSs, it's always fun contemplating the various battery voltages. For example, my 2000 that smoked and the 2200 I replaced it with both use 48v battery strings, something that as an old phone guy I'm just fine with. In fact, the first string I had on the old 2000 was off a decomissioned Nortel PBX.
Seems to me, if I remember right, that the APC 1000 and 1500's use a 24v string, and the stuff smaller than 1000 uses a 12v string?
Strangest one I've seen is an old Toshiba UPS, 1400va, that uses a 60 volt string. Yep, 5x12v in series. No idea if it works; damned if I'll get 5 batteries just to see if the silly thing will power up.
I was talking about cheap cards for the APC boxes, meant to expand on that a bit. What I was referring to is the AP9606, which can usually be found on eBay for around $20 including shipping. Not super useful, in that it can't be used with PowerChute s/w to shut down multiple CPUs as one would hope and as the newer cards will do.
But for that price, you can Telnet in and do basic setup, FTP in firmware update if needed and HTTP a really nice config/status/maintenance menu system to basically do it all.
If you get one, there is one fly in the ointment you need to know. Hopefully, the seller has left the admin password at default. If not, life can get fun. There is a procedure for resetting to factory default. It is known for not always (or often, ever?) working. Failing that, you get a hex editor, ftp the config file and go looking for the password. My luck, naturally, was that I needed to do so. Took about 20 minutes to figure it all out, but I did get success in the end.
Anyway, good grins all around ...
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Message 70078 - Posted: 9 Jun 2016, 18:34:34 UTC

Those 4U 3000VA units that I was hoping to bring home.. those were 96vDC inside. 8 batteries in series.

Newer units (I'd say pretty much anything after about 2005(?)) have smart-charging circuitry though, so you can't usually get away with adding too much AH rating to them. Like I said about those TrippLites.. I pulled the original 7AH batteries out of them and put 12AH ones in to replace them. I would get about 30 minutes at about half-load on those before it was down to just one out of five LEDs for battery remaining, and then the alarm would sound again.

I know with much older units, they didn't care about the batteries, as long as they were the proper voltage. I've heard of people building a shelf outside the window to put 3-8 marine deep-cycle batteries out there, and although it would take 2-5 days for them to get fully charged, even at 100% load on the UPS, you could run for like.. 18 hours.

But more modern charging circuits won't charge for more than 24 hours, and are able to detect if you have too much AH rating, and will just flat-out refuse to charge or use those type of batteries. But you can usually get away with doubling the AH's.
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ReiAyanami
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Message 70079 - Posted: 9 Jun 2016, 19:41:27 UTC
Last modified: 9 Jun 2016, 19:50:34 UTC

Uh-oh, Is SETI down? or just me?

Edit: Was just me...
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Message 70101 - Posted: 11 Jun 2016, 8:40:16 UTC - in response to Message 70100.  
Last modified: 11 Jun 2016, 8:48:06 UTC

Seems to me, if I remember right, that the APC 1000 and 1500's use a 24v string, and the stuff smaller than 1000 uses a 12v string?

All I know is that the Powerchute Management Console tells me that the battery on the APC1000 is at 27.27VDC, internal temp 93.6F.

OK, so that would be a 24v string, as I suspected. If you're interested, the float voltage math is:

2 batteries x 6 cells/batt = 12 cells
27.27 v float / 12 cells = 2.2725 volts per cell, just a tad higher than the recommended 2.25 vpc recommended by most manufactures.

Mine's currently:
4 batteries, 24 cells, running a float of 54.55 v float / 24 cells = 2.2729 vpc.

edit: Internal temp 19.3c, 66.74f. Missed it on first glance.
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