Classroom battery backup?

[pete]

I'd like something that can give 5-10 minutes of runtime to a room of <35 computers (some with CRTS) so that kids can save their work when the power goes titsup. All network kit between client machines and servers is on battery backup.

The previous site manager and I talked around a plan involving a chunky UPS feeding sockets (labelled, with 3 round pins) on the computer room conduit, but we never got as far as a test phase and weren't sure on the safety and legal aspects of ups-fed sockets (specifically, the breakers in the fusebox can't do their job).

Has anyone seen a unit or installer that can set this up safely, or am I in strictly custom job territory. Do any of your schools have generators or battery rooms?

And yes, power cuts happen often enough round here that it probably is worth the money.

[plexer]

In that case I'd speak to a specialist contractor about your wishes and get them to recommend something.

I think they only safe way we could recommend doing this DIY would be a desktop ups per 3 - 4 machines depending on the capacity?

Ben

[GrumbleDook]

I am just wondering about the need for this ...

If the student is working on a file from their home area and they are regularily saving it (or using auto save) then the most they will lose is about 10 mins of work.

I would struggle to justify the expense just for 10 mins of work.

If we are talking about large files pulled down from the server (eg videos for editing) then it is a maybe ... but since these are *large* files (2GB+) then 5 mins on battery might not be enough anyway ...

I believe in redundancy but sometimes the cost is too high and it can be used for other things ...

[Geoff]

Yes, done this in a previous job. Basically you'd have the entire building on an Industrial scale UPS system. You can then further extend this concept and grab a diesel generator if you wish. This will allow you to continue working for several hours if you need to.

You'll need to contact a specialist company, also expect to spend somewhere between £100,000 and £250,000 for a room or £1,000,000+ for an entire building.

[CyberNerd]

for that sort of money, invest in a thin client system - if the client crashes (and the server is kept up by UPS) then the session can be restored and work is saved (Citrix and LTSP does this, not sure about RDP)

[pete]

@Ben
Yeah - tried that, the kids mess about with them because they beep.

@Grumbledook
We had 4 power cuts yesterday, 2 were within 5 minutes of each other. One was in the next lesson and we had one that lasted 1/2 an hour.

It's not just the 10 minutes of work lost, it's classroom time: time spent getting the machines back on, settling the students down and getting them logged in and working again. In winter it's something of a gamble whether we'll have a whole day without a power cut of some magnitude.

[plexer]

Surely your power company should be doing something about this then?

We're not in the dar ages anymore they should be able to provide you with a sensible solution. I see this as their problem to sort out not yours to have to fix.

Ben

[CyberNerd]

We had 4 power cuts yesterday, 2 were within 5 minutes of each other. One was in the next lesson and we had one that lasted 1/2 an hour.

That does sound bad. Another case of management ordering the installation of more equipment without the thought of infrastructure?. Maybe you need to get electricians in for a rewire.

[Geoff]

I think it would be better to try and solve the root cause of the problem rather than papering over the cracks. Have you discussed the reliability of your sites power supply with your power company?

[GrumbleDook]

Definitely *DO NOT* go for a UPS system with that level of fault on your power needs ... yes, you will get the kids to save work and shut down but the batteries will not charge back up in time for the 3rd cut of the day ... and you lose the work anyway.

Invest the money on infrastructure ... or a lawyer to sue the power company / electricians.

If all else fails, invest it in a generator that works on reusable energy and you can sell electricity back to the power company. A sizeable investment but better than a temporary solution like UPSes.

[pete]

Re Power Supply diagnostics

Internal Wiring / Supply:
It's not our internal wiring causing the problem, while it is a bit old there is sufficent juice available to power all kit at all times.

Power Infrastructure:
We are in a bowl at the very end of 3 distribution chains which supply different parts of the town. Much of this supply is overground and on a windy day you can see blue sparks along the main road where the wires blow together.

Central Networks (the infrastructure provider) are aware that the power supply to the whole town is a "known issue", but don't seem to be doing a hell of a lot about it. We are currently in touch with the local council to see what action they have taken, because we need a "bigger than one school" stick" to beat Central Networks with.

@Geoff
Thanks for the figures, we can't afford backup then.

Needless to say, this has been ongoing for some time and I'm sick of it.

[Ric_]

@pete: I think that CyberNerd has hit the nail on the head... thin client may be the way to go.... but I would say that

[Geoff]

If all else fails, invest it in a generator that works on reusable energy and you can sell electricity back to the power company. A sizeable investment but better than a temporary solution like UPSes.

6th formers + exercise bikes?

[pete]

@Ric
Aye, we already have 50 thin clients and I'm looking to replace any "general purpose" machines with thin clients as they die.

I'm aware Citrix can handle a lot more peripheral-wise than RDP, but how does it handle PIC programmers (30-ish kids all using at once, via serial ports or usb-serial converters) or data logging kit(also serial)?

[john]

We have an office block on UPS, its sockets are half UPS half normal power, computers are on the UPS ones, printers, copiers, scanners, fax etc on normal so they dont waste the UPS. Although last time we had a large powercut, I put the kettle on the UPS as we were all dying for a brew and the servers had been shut down as there UPS had run out so the big office one was not being useful anyway by that point so we thought what the heck, I tell ya I was the most popular person in school having power

It has about 10 computers on it and lasts for about 5hrs, its a main control unit and about 5 extended batteries on it. Cannot remember the cost but was no where near the 100K mark I think it was probably nearer the 15K area