gunther_01
Premium
join:2004-03-29
Saybrook, IL
| Battery charging for UPS back-up
What are you guys using for custom battery back-ups for your equipment. I have a site I need 24 volts for, and our normal UPS flavor isn't working long enough... For those times when the company unplugs us for the weekend and such 
Pretty much, what brand or kind of "charging" methods have some of you used? I hope to have a 3 stage charger, but they seem to be about an arm and a leg. I already have the batteries coming. I just need to figure out the charging method or device to get. |
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CMack
join:2004-07-30
canada
| We are about to deploy one of these with 4 batteries, will keep our site up for 20 hours (we hope), more bats, longer runtime. |
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gunther_01
Premium
join:2004-03-29
Saybrook, IL
| reply to gunther_01
Little smaller scale here. Like a 60 Watt 24 Volt load for the single device in use at the site. I bet I could get a week or two from the 4 batteries I think you are refering to 
Iota makes some good stuff. But I am trying to find a different (read, less expensive) method to charge/float a couple 18Ah batteries |
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CMack
join:2004-07-30
canada | reply to gunther_01
Try this then, we use these as well, very good and stable.
»www.magnumenergy.com/MMSseries.htm |
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viperm
Carpe Diem
Premium
join:2002-07-09
Winchester, CA
| reply to gunther_01
Okay are you trying to charge batteries then use those battteries to power A/C bricks? Or are you only using it to charge batteies then your 12/24 volt devices are hooked right to the batteries without power bricks etc.
--
ComTrain Certified Tower Climber. American Tower Certified approved contractor. Wireless consultants. |
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gunther_01
Premium
join:2004-03-29
Saybrook, IL
| reply to gunther_01
Sorry, this is a full DC system I am trying to build. Batteries, charging/float. We currently have a UPS there. It isn't enough (4 hour) for some of these random and fairly common outages. So I figure I will build a DC setup and just run the Metro off of that. Should last longer without all the AC-DC-AC-DC switching and what not. I know it will. I just need a method to charge them.
I have found some variable voltage PS's. The best I can tell I just need to get a good one with decent amperage for the bulk charge, and one that I can also set voltage on. With Probably a diode in the mix to prevent back voltage to the PS from the batteries. |
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viperm
Carpe Diem
Premium
join:2002-07-09
Winchester, CA
1 edit | reply to gunther_01
Try these guts we have used there stuff in the past for A/C to DC and from DC to DC power conversiton.
There are one of the leaders in power stuff not sure if its econoimcal enough for you but I am sure you can call them and tell them what you are looking for and price points.
They have always been helpful with us..
»www.xantrex.com/
Maybe something like this?
»www.xantrex.com/web/id/72/p/1/pt···duct.asp
--
ComTrain Certified Tower Climber. American Tower Certified approved contractor. Wireless consultants. |
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CMack
join:2004-07-30
canada | reply to gunther_01
I confirm Xantrex works, we used to use them on smaller sites but changed them out as we got larger. |
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AMD Phreak
Premium
join:2003-12-14
| reply to gunther_01
I'll say this about any power plant that one builds:
Spend as much money as you can on the power plant. No power equals no equipment.
Case in point, a data center I was at recently, remodeled not too long ago. 70% or so of the remodel cost was in the power plant.
--
"No job is so important, and no service is so urgent that we cannot take the time to perform our work safely."
-- AT&T, Your World, Destroyed.
--Safety One Tower Rescue Certified
--LLigetfa:"Wimax is like teenage sex. Everyone talks about doing it." |
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gunther_01
Premium
join:2004-03-29
Saybrook, IL
| reply to gunther_01
I'm really kind of surprised no one is doing this it seems. But I will keep digging around forums for more brands. I have read up on xantrex they make killer inverters. Our power Co. uses them in their work trucks I just think $200-$300 is a lot for a battery charger. This site only has 12 customers on it. So a $400-$500 UPS is a bit out of line. But it may come to that.
This power "issue" at that location is out of line also |
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Gerard780
Premium
join:2002-01-25
Simpsonville, KY
| I've used »www.samlexamerica.com/products/p···sID=8003 at some sites with good results. This is a $200+ charger though.
I think this one might fit your needs/budget though. »www.samlexamerica.com/products/p···sID=8059
Gerard |
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gunther_01
Premium
join:2004-03-29
Saybrook, IL
| You are THE MAN! Perfect.  |
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nunya
SEE ROCK CITY 475 MILES
Premium,MVM
join:2000-12-23
O Fallon, MO
clubs:
 ·AT&T CallVantage
| reply to gunther_01
I'll second the Samlex. It's the only low cost supply / charger I've ever been able to find.
You're right, if you can keep conversion steps out, it's much more efficient.
--
Looks like Reverend Wright got his wish - God Damn America. |
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trc120
join:2006-02-01
Mosier, OR
| reply to gunther_01
said by gunther_01  :You are THE MAN! Perfect. While the above will work as I am doing the same with 12V, keep in mind this charger does not look like it is specifically designed to have a load like this one: »www.chargingchargers.com/charger···415.html
Something like this will incorporate a low voltage disconnect, but you could accomplish the same thing for less by adding a solar charge controller to a 24V power supply. »www.wlanparts.com/product/TP-UPS···9AH.html
Todd
--
www.MoWiNet.com - Maximizing the Distance |
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switchman
join:1999-11-06
Grand Prairie, TX
 ·RoadRunner Cable
| reply to gunther_01
said by gunther_01 : I hope to have a 3 stage charger On the issue of 2-stage vs 3-stage, the following site recommends a 2-stage if you have a load on the battery. It makes sense if you think about it.
»www.donrowe.com/battery_charger/···ent.html
The choice is between a two or three-stage charger, depending upon its use:
If there are permanent or transient loads on the battery during charging, a two-stage charger has the advantage because its circuits cannot be “fooled” into pushing a higher “absorption" voltage than required for charging.
Without loads during charging, the three-stage charger has the advantage because it provides a more complete recharge. A two-stage charger provides a constant current until the battery reaches its rated capacity and then switches to a “float” voltage. The current then reduces as necessary to maintain the battery at the float voltage. The charger can be connected to the battery indefinitely. A two-stage charger is recommended in most instances since it is the most versatile and can be permanently connected to attenuate the characteristic discharge of unused batteries. A load can be put on the battery or batteries without altering its ability to keep the battery at optimal charge.
A three-stage charger is the most complete charger. It charges the battery at a constant current until the battery voltage reaches a slightly elevated level. The battery is maintained at this voltage while the charging current diminishes to a low value, and then the battery is switched to the float voltage where it can be maintained indefinitely. However, the charger cannot differentiate between a current going to a load on the battery, or being absorbed by the battery, so it can overcharge a battery supplying current to a load. A two-stage charger is preferred for “loaded” batteries and a three-stage for idle or “unloaded” batteries during recharging. Samlex chargers which offer 3 stage charging can be switched to 2 stage if required by simply Adjusting a dip switch. |
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gunther_01
Premium
join:2004-03-29
Saybrook, IL
| reply to gunther_01
In this particular case, the "load" is less then .5 AMP. If the Samlex manual and graphs are accurate, the charger will be floating all the time. But may kick up if the batteries start to fall off a bit. I would guess it will be weeks if not longer before they do that though. And this charger I hope will not mind any. I suppose if it melts down, or burns up my batteries I will find out fairly soon.
But at 18Ahr. I should get anywhere from 36 hours to 60 (might be .3 Amp) hours of run time out of this deal. Which is just great for this crazy location. The power there sucks.
Thank you guys for the info. I will try and send some pics if I get it done next week. |
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