New Server Hardware In Place!

[freeze_time311]

Awesome. It just keeps on getting better.

 

[Mike Baker]

More good news. What else is there left to be done Mike?

 

[Mike Bobbitt]

Next up: I have to address the power situation. Right now we're working off of a dead UPS and we probably need 2 decent ones to cover the networking gear and the server itself.

 

[geo]

Mike, when you get the two UPS' make sure you split the server's power needs over the two... that way, if one goes wacky, the other one can carry the can for a bit.

 

[Mike Bobbitt]

Good plan. I'd intended on getting a "small" one exclusively for the networking gear, but it would probably make more sense to spend the few extra bucks to get one that could handle it all if it needed to.

 

[geo]

two mid sized UPS' are better, in the long run.

I did a little booboo once and accidentaly "reset" one UPS.  Fortunately, the othe UPS carried the can for the time it took the other one to get back on line.  A bunch of alarms squealed but, nothing else.

 

[Flip]

Can the dead UPS be repaired?

They usually just need new batteries.

Usually costs almost as much as a new UPS. ;D

If it were in Edmonton I'd be happy to fix it.

 

[geo]

With lower cost of new kit, refurbishing the old UPS prolly isn't worth the trouble... IMHO

 

[Flip]

All depends.....

If the old one is a relatively large or good one - fix it.
If not - recycle.

Newer ones tend to be electronic kindling if you go too low end.

I've seen a few with the sides bulged out and batteries melted
after a single use!

 

[Mike Bobbitt]

No, the old one is a cheap $120 model. I'm fairly new to the whole UPS thing but it seems like you guys are old hats at it... what sort of characteristics shoould I collect from the gear (amps, volts etc.) to determine the right UPS solution? How much should I over-engineer it by?


Thanks
Mike

 

[McG]

Batteries are typically rated in Watt hours, it would be all too easy if UPS used this system because you can determine roughly if it will meet your needs & for how long it will meet your needs.

It seems UPS are typically rated in VoltAmps (Watts), so if you know the wattage your system is using you can determine an appropriate UPS.  But, you will need to buy a UPS with a higher VA rating than your needs because some of the electrical power is used to convert DC to AC.  I can't help with how much larger you need to go, because I don't know that stuff.

Then there is the question of how long it will keep your system alive for.  Where I've looked I've not seen a hours of protection rating, and without a W hr rating I would not know where to start an educated guess from.

Looks like I'm not going to be much help.  I'll let someone else post now.

 

[Flip]

There are two things to consider.

Capacity ( In Amps ) and for how long ( minutes to hours).

The UPS should be rated for 100% of the total load and overated by 100%
for safety.

The other arguement depends on what is required - Are long outages the norm?
The longer the outage - the hotter the batteries will get.

My concern is to avoid the cheapies as they do tend to age poorly and do pose some risk.
Remember - that the batteries will age and the rated capacity will decline.

If the Hardware takes a total of 5 amps - Get a 10 amp UPS
Check the labels or manuals if you have to to get this spec.

The "VA" rating might not be meaningful. - some vendors lie.

PM me with details if you want - some of this stuff can be subjective.



 






Just a few thoughts. ;D

 

[Mike Bobbitt]

Ok, the server is 10 amps. (Told you I got a big one!) The networking gear is 2.3 amps plus two devices don't have input amps listed. They're 120V 17 watt, can we figure it out from that?

Now this is input amps, I assume we don't care about output?

 

[GAP]

Power=I(current) x E (voltage)

I = P/E

I = 17/110 = .16 amp

 

[Flip]

Nice correction there GAP

As usual, my rule of thumb fails.

For a total of 12.5 Amps we're not talking about consumer junk anymore.
15 Amps is most we can use on a 110v line.

One question, what's the actual current drawn - I suspect it's no where near the 10 Amps
on the power supply.  If we go by actual draw times 2 we should be fine. 

 

[Mike Bobbitt]

One question, what's the actual current drawn - I suspect it's no where near the 10 Amps
on the power supply.  If we go by actual draw times 2 we should be fine. 

Umm... not sure how to measure that... does this help: http://www.antec.com/pdf/flyers/TP3flyer.pdf

It's the specs for the power supply in our server. I'm OK getting two units, one for the srever and one for the networking gear if it helps simplify the problem.


Thanks again for all your help!

 

[Flip]

I get 7 Amps as worst case for the 650 Watt power supply.

I used GAPs formula and used 85% as an efficiency factor.

650W/110V= 5.9A

5.9Amps/.85%= 6.9A

6.9 A (server) + 2.5A(other stuff) = 9.4 Amps

We can also  consider CSAs 80% load factor requirement.

9.4A ( rated ) X 80% = 7.52A  Max. legal normal load

All totaled you are unlikely to draw as much as 8 Amps.

I would use one UPS, even though destributing the load would likely cost less.
There is not much point in some things running when some other things are not.

The single industrial size UPS  is likely to be safer and eliminates any possible issues (noise)
between connecting equipment that are effectively on different circuits.

An electrician could measure the current coming out of the wall receptacle with
a clamp-on Ammeter. The clamp goes around the black wire only.   

My rule of thumb can still work!   :

BTW. that works out to 1650 VA for 110V to 1800VA for 120V

 

[Mike Bobbitt]

Awesome, thanks Flip. You have undoubtedly saved me from (at best) an uninformed decision, or (at worse) a completely inappropriate purchase!

 

[Mike Bobbitt]

Darn... a cursory glance says 1500 VA is the price cutoff... You can get a 1500 VA UPS for ~4-600, next up seems to be a 2200 VA for over $1k. I'll keep looking.

 

[Flip]

2200 VA would likely be a 220 volt type. - 1800 VA is our MAX. ( on a 15 amp circuit.)

I'll check around - see what I can find in my world.