| T O P I C R E V I E W |
| REANZI |
Posted - Jul 28 2011 : 03:36:28 AM
Hello there,I'm having problem to get the suggested IC, LM 301A,can you give me any alternative to that?Also can I use any other regulator instead of LM350, if yes which one?
I'm very happy to join you.
Please when ready send me a link via my e-mail. |
| 12 L A T E S T R E P L I E S (Newest First) |
| Aaron Cake |
Posted - Jan 11 2012 : 10:29:25 AM
quote:
Originally posted by pebe
Aaron, cculd you please explain your reasoning.
If the battery only has to supply current for a one-hour supply interruption during any period of one month, why does the charging circuit have to supply enough current to run the inverter?
An online UPS has not switchover, unlike a standby/offline UPS that quickly switches it's output to an inverter with a relay. So the online UPS must always power the load via it's inverter, meaning that that input switching supply must be capable of providing the full current the inverter needs in addition to a little more to charge the batteries.
I'm just assuming that's how they are set up, I have not looked it up. I guess it could also have a 1:1 transformer with another primary. Ordinarily the load is run directly from mains via the transformer, but as soon as mains drops the inverter kicks in and drives the second primary. There would be essentially no switchover time and the second primary could be used as a secondary during mains operation to charge the batteries. Maybe that's how it's done.
Doesn't seem worth it to build a UPS though. Cheap small ones are $50 at the office supply store. |
| JUAN DELA CRUZ |
Posted - Jan 08 2012 : 11:17:01 AM
So, I think its better to aply your charger in a OFFLINE UPS where the inverter is powered by mains and at the same time automatically charge the batteries and when it fails the batterries stops charging and then powered the inverter. 8-) |
| pebe |
Posted - Jan 07 2012 : 11:32:18 AM
quote:
Originally posted by Aaron Cake
An online UPS needs a charging circuit which can supply the amount of current that it takes to run the inverter. Since the automatic battery charger circuit does about 3A maximum, it won't work for this application........
Aaron, cculd you please explain your reasoning.
If the battery only has to supply current for a one-hour supply interruption during any period of one month, why does the charging circuit have to supply enough current to run the inverter? |
| Aaron Cake |
Posted - Jan 07 2012 : 10:26:41 AM
quote:
Originally posted by JUAN DELA CRUZ
HAPPY NEW YEAR! 
Are you referring to a deep cycle battery?
I will make a Online UPS.. do you think aaron's automatic charger can be use in my application?
Thanks.
An online UPS needs a charging circuit which can supply the amount of current that it takes to run the inverter. Since the automatic battery charger circuit does about 3A maximum, it won't work for this application. I have not taken one apart but I suspect most online UPSs have a very beefy switching supply at the input, which steps the voltage down to battery voltage, which powers the inverter. The batteries are likely in parallel with the output of that switching supply and the voltage of the switching supply is carefully adjusted to avoid overcharging the battery.
Online UPSs are even today, about twice the price of regular UPSs. Mainly because they have twice the parts. Unless your equipment is particularly sensitive a regular old standby UPS is fine. They switch over almost instantaneously. 99% of the time that's what I'm installing. |
| audioguru |
Posted - Jan 06 2012 : 2:16:03 PM
Hi Juan,
I have never used and never made a lead-acid battery charger. My electricity is extremely reliable because it was designed to be reliable with a few backups. The battery in my car is nearly 6 years old and still works fine because all it does is start my car engine for a few seconds each day.
I never looked at Aaron's automatic battery charger. |
| JUAN DELA CRUZ |
Posted - Jan 06 2012 : 08:20:55 AM
quote:
Originally posted by audioguru
Hi Juan,
A car battery is not used in a UPS or inverter, a deep discharge battery is used instead. A car battery is designed to start a car with a very high current for only a few seconds then be immediately recharged and is ruined if it discharges too much.
Hello audioguru,
HAPPY NEW YEAR!
Are you referring to a deep cycle battery?
I will make a Online UPS.. do you think aaron's automatic charger can be use in my application?
Thanks. |
| audioguru |
Posted - Jan 05 2012 : 2:09:32 PM
Hi Juan,
A car battery is not used in a UPS or inverter, a deep discharge battery is used instead. A car battery is designed to start a car with a very high current for only a few seconds then be immediately recharged and is ruined if it discharges too much. |
| JUAN DELA CRUZ |
Posted - Jan 05 2012 : 05:26:50 AM
@Aaron,
Happy New Year! =)
Can your automatic charger can be use in a Online Type UPS? ..With the car battery and a Power Inverter is the Load.
|
| Aaron Cake |
Posted - Jan 02 2012 : 10:10:28 AM
Yes. Once the voltage of a lead acid battery matches that set by the pot, the charger cuts out. |
| farahalid |
Posted - Jan 01 2012 : 3:14:05 PM
what means by automatic battery charger???? that the charger can cut off the supply when the battery full???? |
| Aaron Cake |
Posted - Jul 30 2011 : 10:46:59 AM
Use the automatic battery charger at http://www.aaroncake.net/circuits/charger2.asp instead. It's a better circuit and doesn't use an op-amp. |
| audioguru |
Posted - Jul 28 2011 : 07:56:47 AM
quote:
Originally posted by REANZI
I'm having problem to get the suggested IC, LM 301A,can you give me any alternative to that? Also can I use any other regulator instead of LM350, if yes which one?
Please when ready send me a link via my e-mail.
Both parts are very common and are made by many manufacturers so there are no replacements.
If you were here in Canada then you can buy them at Digikey who has 3953 LM301A opamps in the DIL case (and many more in a surface-mount case) and they have more than 23,000 LM350 ICs in stock. If I order before 8:00PM then they are delivered to me the next morning. |
