Ups Upgrade

[luckey007]

My living area is notorious for frequent blackouts and I do hope to fix a security camera system I wanted a UPS that can last for long.

What I did:

1.Asked My favorite techie friend about my idea. After the discussion his answer was it can be done if I can find a solution to the heat.

2.Search the Youtube & blogs. Youtube had several videos. Almost all of them from USA and the question raised was can I use the Chinese UPS circuit as they are using their old UPSs.

3.Accidently met a man who makes inverters in small scale and he told me that "Sir, relay 5k thiena circuit eka rath wenawa wediyi, relay 2k thiena eka rathwenne ne.Ekak thienawanam wede lesiyenma karatheki". When I check my circuit boad onece in the home I found that my board has only 2 relays. And it was the biggest green light. If one of you reading this post know the reason behind this please let me know. The guy who told me this knows only that middle 2 relays are over heating.

Then I started my project...

[luckey007]

My UPS circuit board...Note 2 relays...

I can't UPLOAD images. says image shack is not allowed. friends HELP

Edited February 12, 2015 by luckey007

[Rumesh88]

I am unable to understand what exactly your problem is. Do you intend to power up your whole house load with the UPS or only essential loads like CCTV? What is the capacity of your UPS (800VA, 1kVA, etc?)?

[Jor-el]

Use imgur

[bycap]

I'm confused what you say here. any way if the frequent blackout is the main concern I suggest you to use a back up generator. generally a generator needs few minutes to warm up to provide the requested power. If you cant tolerate that short time too, use a UPS system for that period. having a UPS system is costly than a generator I think.

[maersk]

I also tried once, but not very successful. Technically you can do it with modifications but after those modifications you'll have a badly design Inverter with lot of limitations. Why not use a proper inverter with suitable battery capacity?

If you need extra back up power only for you CCTV system go for a larger UPS. My 8 ch sys run for about 30 mins with smallest (600 VA) UPS without its monitor.

Answer to you question about heating - both UPS as well as Inverters generate heat but since UPS is designed for shorter operation it is designed to withstand that much heat only. Usually in a inverter there are cooling fan/fans with heat sinks apart from PCB design to handle more heat for longer periods.

[luckey007]

I am unable to understand what exactly your problem is. Do you intend to power up your whole house load with the UPS or only essential loads like CCTV? What is the capacity of your UPS (800VA, 1kVA, etc?)?

Only essential loads. CCTV, Router,Phone chargers..... I am afraid that servant deliberately off the power and say "Maththiya, ada dawasema light thibune ne".

[luckey007]

Use imgur

Thanks

[The Don]

IE Tech sells fairly good quality inverters which can be used in conjunction with motor batteries. I think the power produced is good enough for computer applications.

I've noted most of the time the issue with UPS are batteries not the circuitry themselves. Sadly the quality of items imported to SL has really deteriorated. My old Fenton UPS lasted a decade with the original battery working for good 7 years with diminishing capacity. The two batteries replaced since lasted about a year and a half each, at which point the inverter also gave up. I replaced that with a UPS from an IE subsidiary Vence, of which the battery promptly gave up after just over a year (so no warranty). It now has a new battery and if this thing also kicks the bucket that soon, I'm going to bring one down with me from the UK at about twice the price and hope for the best!

[Rumesh88]

Only essential loads. CCTV, Router,Phone chargers..... I am afraid that servant deliberately off the power and say "Maththiya, ada dawasema light thibune ne".

Well if that's the case you need to plan for something like a 6-8 hour backup time on your essential loads. This is not possible with simple UPS units even with modifications. However, if your essential loads can be made to run on 12V DC, then you can use a 12V deep cycle lead acid battery (not automotive batteries, they will not last long) of appropriate capacity (this depends on the total load and expected back up time) together with a charging system. An additional advantage is that you can even use a solar panel to supplement the charge from mains power.

[The Don]

Well if that's the case you need to plan for something like a 6-8 hour backup time on your essential loads. This is not possible with simple UPS units even with modifications. However, if your essential loads can be made to run on 12V DC, then you can use a 12V deep cycle lead acid battery (not automotive batteries, they will not last long) of appropriate capacity (this depends on the total load and expected back up time) together with a charging system. An additional advantage is that you can even use a solar panel to supplement the charge from mains power.

Rumesh, explain deep cycle lead acid batteries please.

[Rumesh88]

Rumesh, explain deep cycle lead acid batteries please.

Both deep cycle and automotive batteries have the same chemistry but automotive batteries are physically optimized for high cold cranking amp (CCA) but less reserve amps. The deep cycle batteries are other way round. One main design criteria is the plate thickness and the number of plates in a cell. Deep cycle batteries have thicker solid plates whereas an automotive battery would have plates made of spongy lead. The AGM (absorbed glass mat) batteries found in UPS units are deep cycle batteries but they have a very small charging window (sensitivity to temperature, over-charging etc). Then there are gel type deep cycle batteries and of course the normal freely ventilated or flooded deep cycle batteries. The lead acid batteries found in electric fork lifts, golf carts and solar applications are all deep cycle batteries. While the life expectancy of an automotive battery is like 2-5 years the deep cycle batteries are expected to operate over 8 years. I have come across Hitachi batteries operating in fixed applications for more than 15 years with 75% of their design capacity still in tact. Another difference is the specific gravity of acid solution used and the total acid volume. In an automotive battery the acid sp.gr is 1.26 to 1.28 but in a deep cycle battery battery this can be like 1.24. So for the same battery capacity you need a higher acid volume in a deep cycle battery (It is the total number of acid moles among other things that decide the reserve capacity - for those who remember their chemistry).

Edited February 13, 2015 by Rumesh88

[luckey007]

My bad. I have already bought an automotive battery. I saw about deep cell battery in those videos. But thought that they are not readily available and expensive in sri lanka and top of them assumed there is no significant difference. Anyway the battery has a 2 year warranty and hope it will run at least 2 years.What to do.

[Rumesh88]

My bad. I have already bought an automotive battery. I saw about deep cell battery in those videos. But thought that they are not readily available and expensive in sri lanka and top of them assumed there is no significant difference. Anyway the battery has a 2 year warranty and hope it will run at least 2 years.What to do.

Do not worry now that you purchased the battery cos there is a price advantage. If you haven't filled up the battery (assuming your battery is freely ventilated type not a sealed one) with acid, what you can do is to fill with acid (Sp gr 1.28) to the bottom level mark and fill the rest with distilled(deionized) water. That should give you a specific gravity of around 1.24. These are bit of a maka bass or rule of thumb methods but should work in practice. If your battery has a three color indicator (red, green and white thing) and if you fill up with sp.gr 1.24 acid you may get white (need charging) indicated even when your battery is fully charged. If all is done now forget these and just make sure the acid level is always at the top level and does not go down appreciably (by let's say 5mm) within the first 6 month usage. If it goes down frequently (if you need to fill up every month), that means your charging system is over charging the battery which would result in excessive oxygen generation thus causing premature oxidation of plates. Target for a service life of at least four years.

Edited February 16, 2015 by Rumesh88

[luckey007]

Do not worry now that you purchased the battery cos there is a price advantage. If you haven't filled up the battery (assuming your battery is freely ventilated type not a sealed one) with acid, what you can do is to fill with acid (Sp gr 1.28) to the bottom level mark and fill the rest with distilled(deionized) water. That should give you a specific gravity of around 1.24. These are bit of a maka bass or rule of thumb methods but should work in practice. If your battery has a three color indicator (red, green and white thing) and if you fill up with sp.gr 1.24 acid you may get white (need charging) indicated even when your battery is fully charged. If all is done now forget these and just make sure the acid level is always at the top level and does not go down appreciably (by let's say 5mm) within the first 6 month usage. If it goes down frequently (if you need to fill up every month), that means your charging system is over charging the battery which would result in excessive oxygen generation thus causing premature oxidation of plates. Target for a service life of at least four years.

Thanks, Thanks a lot for sharing your knowledge. The battery is already filled[Low maintanance type of battery.]Shall I remove some acid and fill with distilled water?Is it okay to do it with a syringe?

And I am unable to upload the pictures even using imgur. Please help.

[Rumesh88]

Thanks, Thanks a lot for sharing your knowledge. The battery is already filled[Low maintanance type of battery.]Shall I remove some acid and fill with distilled water?Is it okay to do it with a syringe?

And I am unable to upload the pictures even using imgur. Please help.

No. Don't worry about it now. It is not going to make much of a difference and it is not a big deal. It is in fact not the cost that matters here but the reliability. After using a auto battery that cost you in Rs. 10K region for 4 years in a UPS, you should be able to make up your mind to dispose it. But in the meantime you certainly do not want your UPS to under perform after a couple of years do you? Now that you have the battery concentrate in maintaining it so that it would give you a reliable service over its life period. So better to pay attention to your charging system. Make sure the battery is floated (ie when it is idle and fully charged) at around 13.4 to 13.6 volts and it is not exposed to high ambient temperatures. Ideal method to maintain a battery is to float around above voltage with a compensation for temperature changes and then to perform an equalizing charging procedure periodically. But these things are a bit of an overkill in your situation.

[luckey007]

Dear Rumesh, The battery of a Hybrid[eg:Prius] and a EV[eg:Leaf] fall in to deep cycle category? Or are they different?

[Rumesh88]

Dear Rumesh, The battery of a Hybrid[eg:Prius] and a EV[eg:Leaf] fall in to deep cycle category? Or are they different?

Hybrid and EV batteries are not lead acid but NiMH or Li-ion batteries. Their charging characteristics are different from those of lead acid batteries and are meant for repeated charge and discharge cycles just like the battery in your mobile. However those batteries are not suitable for stationary applications for they are expensive compared to lead-acid ones and also they are not suitable for keeping on float charge over a long period. Above vehicles have a AGM type 12V lead-acid battery too to power up accessories. But this 12V battery is too expensive to be of any practical use in application like yours.

Edited February 19, 2015 by Rumesh88