asterisk users - May 2005 - UPS rating for SOHO asterisk box

Slightly OT, but I think this is of possible interest to many of you,
I need to get a UPS for my asterisk box. They are rated in VA but I
can't quite figure out how that converts to real life.

I have a PIII-800 box with two X100P and one TDM400P plus graphics
adapter, an IDE hard drive etc. Will a small 400VA box be enough for
this?

tia

Hi,

Let me try to answer this one.

Assuming your P3-800 is using a 300watt power supply, then in a full 
load condition, convert to VA, it will be 300/0.6=500VA. So, it is 
greater than your small 400VA box. So, you need a bigger ups. Of course, 
if your power usage is actually much lower than 300watt which in most 
cases it is, then your 400va box may be ok, but then you are taking a risk.

Another thing to consider regarding the ups is the runtime, depending on 
the hours and minutes you want the ups to supply power to your asterisk 
box, you may need to add more batteries to the ups.

cheers

Wilson Pickett wrote:
>Slightly OT, but I think this is of possible interest to many of you,
>I need to get a UPS for my asterisk box. They are rated in VA but I
>can't quite figure out how that converts to real life.
>
>I have a PIII-800 box with two X100P and one TDM400P plus graphics
>adapter, an IDE hard drive etc. Will a small 400VA box be enough for
>this?
>
>tia
>_______________________________________________
>Asterisk-Users mailing list
>Asterisk-Users@lists.digium.com
>http://lists.digium.com/mailman/listinfo/asterisk-users
>To UNSUBSCRIBE or update options visit:
>   http://lists.digium.com/mailman/listinfo/asterisk-users
>
>  
>

> Another thing to consider regarding the ups is the runtime, depending 
> on the hours and minutes you want the ups to supply power to your 
> asterisk box, you may need to add more batteries to the ups.
Regarding this, I have done this hack yesterday:

- Remove the battery from an existing UPS
- Rewire the UPS onto biggest car lead acid battery (12v) you can find.

Et voila! Bigger capacity. Put the batteries in parrallel and you do get 
monstruous UPS capacity... the only trouble with it is that re-charging 
the batteries may take some time.

-- 
Ykoz Un Max - La VoIP en pr?-pay?!
Essayez gratuitement - 5 cr?dits offerts.
---> http://ykoz.net/voip/max <---

On Tue, 2005-05-31 at 13:22 +0400, Jean-Michel Hiver
wrote:
> > Another thing to consider regarding the ups is the runtime, depending 
> > on the hours and minutes you want the ups to supply power to your 
> > asterisk box, you may need to add more batteries to the ups.
> 
> Regarding this, I have done this hack yesterday:
> 
> - Remove the battery from an existing UPS
> - Rewire the UPS onto biggest car lead acid battery (12v) you can find.
> 
> Et voila! Bigger capacity. Put the batteries in parrallel and you do get 
> monstruous UPS capacity... the only trouble with it is that re-charging 
> the batteries may take some time.
And place the battery in a well ventilated environment :)

You could give it a boost with a car charger.

-- 
Dave Cotton <dcotton@linuxautrement.com>

> Another thing to consider regarding the ups is the runtime, depending on
> the hours and minutes you want the ups to supply power to your asterisk
> box, you may need to add more batteries to the ups.
No worry there, since the modems (upstairs) will be unpowered as well. 

Although the asterisk box recovers pretty well from a short power cut,
it is risky to allow these to happen at all. This is why I want the
UPS, not for autonomy.

>I have a PIII-800 box with two X100P and one TDM400P plus graphics
>adapter, an IDE hard drive etc. Will a small 400VA box be enough for
>this?
It's tricky sizing UPS'es to be bang on the money. The rule-of-thumb
calculation for VA is watts/.6 . So, for a 200 watt power supply / .6 is 333
VA. Tricky part is, a 200 watt PSU is max power, which your PC will not draw
all the time. You want to be bang on the money, so you have to determine the
watts of every individual component like this:

(numbers out of my ass)

HDD 		35W
Mobo & CPU	80W
Video		10W
NIC		5W
TDM400	20W
----------------
TOTAL		160W = 266 VA

In my experience, oversizing your UPS gives you a comfortable margin, and
these days, pricing between, say, a 400 to 600 VA is minor, and you get
added runtime as a bonus. But if you want a decent runtime on your box, and
it's of the 200W PSU variety, the 400VA will probably be OK given what you
have stated. 

hth

> -----Original Message-----
> From: asterisk-users-bounces@lists.digium.com 
> [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of 
> Jean-Michel Hiver
> Sent: Tuesday, May 31, 2005 5:22 AM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: Re: [Asterisk-Users] UPS rating for SOHO asterisk box
> 
[...]
> Regarding this, I have done this hack yesterday:
> 
> - Remove the battery from an existing UPS
> - Rewire the UPS onto biggest car lead acid battery (12v) you 
> can find.
> 
> Et voila! Bigger capacity. Put the batteries in parrallel and 
> you do get monstruous UPS capacity... the only trouble with 
> it is that re-charging the batteries may take some time.
[...]

Congratulations....you've just given this part-time small town fire
marshal and 14-year fire service veteran nightmares.

Kids....do NOT try this at home.  The inverters in small UPSes are not
designed to deal with runtimes that exceed the batteries in them.  If
you run this setup well past the time it was designed to run (by adding
3, 4, or more times that battery capacity it was ever designed to have)
that chances of a catastrophic inverter failure (meaning flash, boom,
fire) are very real and very likely.

Daryl

Living in the Caribbean, this is a big issue for us. I would avoid the
little SOHO UPS units, they will not last very long. Always over rate your
UPS and I would not play with external batteries, it is more trouble than it
is worth. You can buy refurbushed 3U rack mount UPS on Ebay for little
money, usually telco grade and about 1500 VA.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=44963&item=5202751352
&rd=1&ssPageName=WDVW

Chris Mason
www.anguillaguide.com
Tel:  (305) 704-7249 Fax: (815)301-9759  
> -----Original Message-----
> From: asterisk-users-bounces@lists.digium.com 
> [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of 
> Wilson Pickett
> Sent: Tuesday, May 31, 2005 4:01 AM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: [Asterisk-Users] UPS rating for SOHO asterisk box
> 
> Slightly OT, but I think this is of possible interest to many 
> of you, I need to get a UPS for my asterisk box. They are 
> rated in VA but I can't quite figure out how that converts to 
> real life.
> 
> I have a PIII-800 box with two X100P and one TDM400P plus 
> graphics adapter, an IDE hard drive etc. Will a small 400VA 
> box be enough for this?
> 
> tia
> _______________________________________________
> Asterisk-Users mailing list
> Asterisk-Users@lists.digium.com
> http://lists.digium.com/mailman/listinfo/asterisk-users
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users
> 
>

Hello, 

APC has a nice selector tool on their website. 

http://www.apc.com/tools/ups_selector/index.cfm

It asks several questions to recommend an APC solution. it even gives
you a percentage of the capacity of the ups systems capacity. 
> -------- Original Message --------
> From: Wilson Pickett <spamsucks2005@gmail.com>
> Date: Tue, May 31, 2005 3:00 am
> 
> Slightly OT, but I think this is of possible interest to many of you,
> I need to get a UPS for my asterisk box. They are rated in VA but I
> can't quite figure out how that converts to real life.
> 
> I have a PIII-800 box with two X100P and one TDM400P plus graphics
> adapter, an IDE hard drive etc. Will a small 400VA box be enough for
> this?
> 
> tia

> >I have many sites that have a 35amp Charger with 2 x 400ah 900CCA deep
cycle
> >batteries (10 year warranty), and 1000VA inverters.
> >  
> >
> Those deep cycles batteries look quite appropriate... in which kind of 
> store do you get them?
In the US just about any store that sells batteries including Sears,
InterState Batteries, most automotive parts stores, etc, etc. Just 
ask them.

You see a lot of the deep cycle batteries used in fishing boats where
they power electric trolling motors.

> -----Original Message-----
> From: asterisk-users-bounces@lists.digium.com 
> [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of 
> Terry H. Gilsenan
> Sent: Wednesday, June 01, 2005 5:05 AM
> To: 'Asterisk Users Mailing List - Non-Commercial Discussion'
> Subject: RE: [Asterisk-Users] UPS rating for SOHO asterisk box
> 
> 
> I have many sites that have a 35amp Charger with 2 x 400ah 
> 900CCA deep cycle batteries (10 year warranty), and 1000VA inverters.
> 
> The combination makes for perfect power and about 2.5 days 
> run time with my network kit whish consists of several Dlink 
> wifi access points, 1 xbox (hacked into a router/firewall) 
> and a vsat system.
> 
> Total cost for the power kit AUD$1400 all up, and not a 
> single second of downtime in over a year.
[...]

Yep....you can (somewhat) build your own UPS with peoperly rated
equipment.  As a matter of fact, most telco installations don't have
"monolithic" UPS's (like you'll see in most larger
datacenters....you
know..the big box that says Liebert on it), they use racks of batteries
with separate charging circuits.  Most of the equipment runs directly
off of the battery voltage, but you will find places with some inverters
as well.  Of course, the room is properly designed (spaced,
non-combustible racks, fire detection and supression systems, etc.) and,
in most jurisdictions they also have to carry one or more operational
permits (current Internation Fire Code requires permitting for stationar
lead-acid battery systems exceeding 50 gallons liquid capacity). 
> On the flipside, I have seen a ups flare when the transformer 
> overheated and melted the varnish, nasty!
I've seen completely unmodified (although not properly maintained) UPSes
as large as 5000 Va completely melt down to the point where they
destroyed their own chassis, damaged the rack they were sitting in, and
activated the clean-agent supression system in the rooms they were in.
This was actually a big problem with one of my customers....they hadn't
been maintaining their UPSes....the "replace battery" lights had been
lit for months (they had all been purchased at about the same time).
Within a span of about 3 months, 4 of them melted down similarly.  A
quick call to APC revealed that the batteries in these units were rated
for about 12 monts less than they had actually been in service, and a
simple battery replacement would have prevented the problem (the chassis
was rated for something like 3 sets of batteries...whatever the lifespan
of the batteries was....3 years I believe).

So, don't do stupid things with high voltage, like modifying equipment
that wasn't meant to be modified, using undersized equipment, failing to
properly vent batteries, or storing your contraption on or near
combustibles.  It's just NOT worth the risk.  Take it from someone who's
pulled his share of bodies (of both the live and dead varities) out of
buildings.  I've seen way too many fires started by electrical system or
device "modifications" similar to those described in previous posts.
And most people who do things like this just never consider the life
safety risk involved until its way too late.

I'll get off my soap-box now and get back on topic.

Daryl