21/07/2004 @23:21:56 ^02:22:10
1845 <Spark> matt says go and do something with your life because your updates are boring
Oh no!! And this is a really long boring update about stupid hardware shit, whatever shall we do.
IT'S JUST A BOX WITH SOME ELECTRONICS AND A HUGE BATTERY IN IT
Powercuts occur on average about once or twice a year here, ranging from dropouts lasting half a second to several-hour losses. As such I always meant to get some sort of power protection but cost and various other things always made me put it off, stupidly. Even the last powercut, the effects of which were apparently pretty severe, was an entire month ago. But finally something has been done.
Last week I took delivery of an APC SmartUPS. It's a pretty old model with a serial connection. I got the 620VA version because I wanted one that's powerful enough to run two computers a cable modem and a big monitor. It surprised me when it arrived, it was a lot smaller than I was expecting but it was really, really heavy. The battery sparked at me when I connected it up inside the unit like the instructions said, but I was expecting it.
Two IEC320 plug to IEC320 socket leads were supplied, the intention being you get your old computer's power cable with whatever strange plug your country has on one end and an IEC320 socket on the other and use that to power the UPS. Then you put the plugs on the end of the supplied cables into the sockets on the UPS and the sockets on the other end of the cables into the plugs on the back of your computer. I guess this would be better with diagrams but I'm not going to make any.
Note on terminology: plugs have pins (sometimes called male) and sockets have holes (and are sometimes called female) You might think the plug is the thing on the end of a cable and the socket is the thing on the box you put the cable into, but no. Somewhat embarrassingly it took me an awful long time to find a good way to remember which is which. This might explain a lot.
Anyway having two IEC power cables (that is, a power cable with an IEC plug on one end and an IEC socket on the other) I could put the two computers on UPS power but I still needed some way to power the cable modem and the monitor. The monitor could be powered off another IEC cable but the cable modem runs off one of those DC transformers so it needs a regular socket to plug into. So having talked to Iain it was time for a bit of DIY...
It turns out you can go to an electronics shop and procure an unwired IEC plug, an unwired 4-way trailing socket and a length of regular mains cable. These can then be joined together. It's just like wiring regular plugs only more fiddly, especially in the case of the IEC plug which is about half the size of a normal British mains plug. I spent all afternoon putting this thing together and I was quite pleased when I tested it and it worked. Also it means I have a spare 4-way adaptor because I preferred to make a completely new device rather than fuck up an old one; and it's black, unlike all the others which are white, so I can tell which one is on battery backup. Not that it matters much as its right under the table and inaccessible without considerable effort.
While shopping I also purchased a small length of Ethernet cable because the UPS has sockets for network surge suppression. Instead of plugging your modem's ethernet wire straight into your computer you plug it into the UPS then put a wire from the corresponding socket on the UPS to the computer. This was probably unnecessary as firstly any power surge would reach the cable modem before it hits the UPS's power surge suppression and secondly as far as I'm aware it's a fibre optic cable, it runs on light, not electricity like a phone wire, so how exactly are you going to get a power surge? Oh well, it was more for completeness than anything else.
So finally today I rearranged all the cables, put in my specially made 4-way adaptor, plugged everything in, and turned it all on. Happily nothing exploded, even when I plugged the Risc PC and its monitor in as well and thus had three computers, two monitors and the cable modem running off the UPS (and I simulated a power loss and it coped) I am going to say this has so far been a worthwhile endeavour, although it could still all fail so don't go bringing this up as a counterexample when I say I fail at everything I do.
Okay, you want reasons: well firstly I haven't set up any kind of UPS monitoring software on the computers, because caco (the server) doesn't have a free serial port and putting it on baron (the desktop) seems highly illogical. That means I can't tell how long the UPS will last if the power drops out and I still have to shut everything down manually. Secondly, the UPS overload indicator comes on for a fraction of a second when the monitor turns on, but I think that's just a transient and can safely be ignored provided I don't turn the monitor on and off repeatedly. Thirdly and perhaps most importantly I suspect that my wiring job isn't quite up to scratch and especially the wired IEC plug is a shade loose. I suspect this because when I first plugged it into the UPS and turned the UPS on I had to tap the plug to get the light on the 4-way adaptor that indicates it is powered, to come on.
Oh well. Let's just hope it's been worth all the trouble, I guess. We'll know the next time the power fucks up