Practical and H&S implications of using battery racks?

[pete]

As I've mentioned before we have rubbish power.

The power went off yesterday for 3/4 hr, then for 10 minutes and then again from 10pm last night until 9.30 this morning. Depending on what happens today, the school might be closed until the current problem (damp in substation / cabling) is fixed.

I had to wait for the UPS' to have sufficient charge before I could restart the network (enough power to restart on battery and safely power off on battery of necessary).

The "getting power company to do something" is still an ongoing thing. We need to beef up the server rooms battery backup and I was wondering whether it would be more sensible just to use battery racks, since they're easier to expand.

Has anyone got this setup and (assuming everything was installed by a qualified electrician) what are the practical and health & safety implications of having battery rack in the server room.

We'd be using gel cells preferably, but maybe truck / tractor batteries.

[CyberNerd]

but maybe truck / tractor batteries.

These can give off Hydrogen gas when charging.

[DMcCoy]

They might explode? Thats an issue I would have thought.

Are they designed for prolonged high drain use? Temperature limits? Surge protection? Overload protection? Voltage regulation? Emergency shutdown (See overload :P)?

Look at some Enterprise UPS equipment. Get it wrong and you could fry the lot (or kill someone).

[pete]

The reason we were looking at wet cells was better performance / longer life than gel cells. A bit of research has turned up a better gel cell that uses fibreglass matting to prevent the bubbles. It doesn't mention whether the hydrogen issue is dealt with. Since it has valves, I'm guessing not.

The server room does have exceptionally good airflow (2x redundant air-con units), but I'm not sure whether that's sufficient. I assume vent systems to deal with flammable gas are a specialist item?

The cells would be designed for the job - I use "truck battery" loosely and everything would be done to code - we don't mess about where the servers are concerned.

Re: enterprise UPS equipment. Normally it _is_ a UPS wired up to battery trays or a big cabinet with battery trays inside with the UPS electronics.

Battery trays just seem more sensible in terms of expandability.

[Geoff]

What about a diesel generator?

[Irazmus]

Or a wind turbine?

[localzuk]

What about a diesel generator?

This is what I'd be looking at if our power was that bad. Have a generator that auto-kicks in when the power goes down (with UPS's to take the strain until it kicks in).

[DMcCoy]

The reason we were looking at wet cells was better performance / longer life than gel cells. A bit of research has turned up a better gel cell that uses fibreglass matting to prevent the bubbles. It doesn't mention whether the hydrogen issue is dealt with. Since it has valves, I'm guessing not.

The server room does have exceptionally good airflow (2x redundant air-con units), but I'm not sure whether that's sufficient. I assume vent systems to deal with flammable gas are a specialist item?

The cells would be designed for the job - I use "truck battery" loosely and everything would be done to code - we don't mess about where the servers are concerned.

Re: enterprise UPS equipment. Normally it _is_ a UPS wired up to battery trays or a big cabinet with battery trays inside with the UPS electronics.

Battery trays just seem more sensible in terms of expandability.

Is the aircon going to be on during a power cut?

My server room heats up very fast when the air con is off.

[DMcCoy]

Oh, my aircon unit takes 90 amps to start, so you will need big power if you do want to run them :P

[Andrew_C]

Air Con is no use in this context for a more fundamental reason. The vast majority of units siply re-circulate chilled air. This will not clear any gas.

[Ric_]

Surely, during a power cut, there will be no PCs that require the servers

[djm968]

Move the servers to rack space in a hosted environment and let them deal with the power issues!

[pete]

@All
Yes, I realise that we're close to the "Sod it, lets turn everything off and go to the pub" stage of the game and we're reaching the point that we've done all we sensibly can.

This isn't a "make a super-redundant zero downtime solution", it's a "what's the best way of ensuring we have a bit more juice?" question.

@Geoff
We've considered a generator, but the server room is on the first floor and in the middle of the school buildings with either classrooms or the carpark around it. I'm not sure where we'd put it.

@Wind turbine
We already have one actually, powers some stuff in physics. (not enough output for a server room).

@aircon
Server room stays cool enough for about 3/4 hr without aircon.

@hydrogen + aircon
I didn't think it would work. We have a battery rack for emergency lights somewhere, I'll have to see how that's set up.

@Ric
Yes, but servers are like old people....... Bloody sims server was sulking about its array when it came back up. Nothing wrong with the disks and it shut down cleanly on battery - still had to rebuild the array once I'd convinced it the disk was good.

[Ric_]

@Ric
Yes, but servers are like old people....... Bloody sims server was sulking about its array when it came back up. Nothing wrong with the disks and it shut down cleanly on battery - still had to rebuild the array once I'd convinced it the disk was good.

Perhaps you could set different timeouts for the shutdown of diffeetn servers. Newer servers could be shutdown after only a couple of mins, leaving more juice for the older servers to run longer.

It might also be worth replacing the old servers with new ones that use ULV processors, therefore requiring less juice in th first place.

[john]

Have a look at the MGE/APS Solutions (MGE and APC Merged over half term) you get some great units there. You buy battery modules and the MG ones seem to last forever without going wrong or leaking unlike the APC ones that in the larger ones always seem to end up splitting or leaking. You can get them into the 100's of KVs so plenty for a school comms room.