Ups dc output problem.....

May 2, 2012 at 05:56:44
Specs: Windows XP
I will try to explain my problem as short as possible.

I was using a UPS which always get into trouble. I went to local UPS service guy, who suggested to change the board(PCB). so, i accpected and he change to new PICI6f676 PCB. Every thing works fine...but i am not getting backup.

with Exide 100ah battery i get 90minutes backup for 1 computer with crt monitor.

I had doubt on the i removed the UPS and borrowed inverter from my uncles house and checked with the battery....i get 8hrs backup for 1 computer with crt monitor.

To my knowledge the problem is in the UPS....because i checked how much current UPS is dragging from the battery in DC mode.

The Output Current difference In Amps between the 2 kits i checked.

In Inverter - 1system, 1tubelight, 1 fan = 1.9 to 2.00 Amps

In UPS(PICI6F676) - 1system, 1tubelight, 1 fan = 8 to 9Amps

with noload the ups is taking 1.5Amps from the battery. So, the problem is the output current from the DC. how to fix this... please help me...

for u r information the charger unit works very fine.

See More: Ups dc output problem.....

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May 2, 2012 at 07:10:20
Inverter / Home UPS ( Eco Model )
PICI6F676 based design

12V 300VA to 800 VA PCB

Range Available : - 300VA, 600VA, 800VA / 12V system.

Battery Charging Current :- 8 / 11 ± 0.5 Amp. DC.

Your comparison isn't valid unless your uncle's inverter has the same max rating - 800VA

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May 2, 2012 at 07:41:03
my uncle inverter is 650v. My question is when no load why the energy is consumed from the battery. Unless i shutdown the UPS in DC mode...the energy is consumed at the rate of 1.5Amps with no load.

with no load that is very important point....its PCB problem or transformer problem...who knows...

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May 2, 2012 at 16:00:35
I think you don't know enough to safely repair this.
A UPS may have voltages way in excess of the line voltage. Capacitors used in them can kill you.

Just buy a new one.

Hang up and live.

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May 2, 2012 at 20:05:31
Due to the relatively low cost of UPS' they do not pay to repair except maybe replacing the battery if you can get a decent price (aftermarket) maybe once in the life of the UPS. Other repairs are not worth the time and expense (or the risks mentioned by jefro). Just purchase a new one. If you liked the brand, its quality and service life, stay with the same brand, if not then try another. If you need longer run times then look for a larger rated one.

You have to be a little bit crazy to keep you from going insane.

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May 3, 2012 at 08:06:56
Inverter / Home UPS ( Eco Model )
PICI6F676 based design



Jumper Selections for :- Inv / UPS Mode, Normal /High charging, Batt. Voltage boost.

Does yours have those options ?

Does your Uncle's inverter have similar options ?


"with Exide 100ah battery"
sounds like you're using a car (vehicle) battery, which has a much higher ah rating than a typical pre-packaged UPS meant for a computer system has.

In any case, it would take a lot longer to re-charge a battery with that capacity to it's full capacity after it has been deeply discharged than it would for a battery found in a typical pre-packaged UPS meant for a computer system, and it's going to require current from whatever is charging it during that time.

Typical vehicle batteries aren't designed to stand up to being deeply discharged. If you are going to use a high capacity battery, you should use one that IS designed to stand up to being deeply discharged without being damaged, e.g. one meant for use with an electric boat motor, or meant for use as a second battery for a recreational vehicle.

"I had doubt on the battery"

How old is it ?

Batteries can develop internal shorts, caused by conductive crap that has accumulated under the plates inside the battery that is touching the bottom of the plates (if you move the battery or tilt it from horizontal, or if the vehicle it's in physically jars the battery while moving, that crap may not cause proplems sometimes, cause problems other times), or by physical damage inside the battery otherwise, e.g. cracking of the plates, and that's more likely the older the battery is, the more physical jarring it's been exposed to.

Symptoms I've seen of an internally shorted vehicle battery.

When you use the battery with a vehicle, the greatest amount of current is drawn from the battery while you are starting the vehicle.

One battery produced electrical arcing sounds at the battery that came from within the battery while that large amount of current was being drawn from it, but made no sounds after the vehicle was running.

The battery may get HOT rather than just warm when it is being charged.

The (lead acid) battery may not read 12.6 volts after it has been charged and has sat for a while with no load on it - it has a lower voltage.

Or - the battery may NOT read 12.6 volts immeditely after or a a short time after shutting off the engine - it has a lower voltage.

When there's a situation that has discharged the battery, the voltage reading of the battery may drop a lot faster than it does for a good battery. E.g. someone left a car door open overnight, which resulted in the interior light staying on all that time. The voltage was 10.x volts the next morning, rather than higher than that.

My most recent experioence -
When the vehicle is running, the voltage reading is a lot lower than it should be, when there's nothing wrong with the charging system, in comparison to the same vehicle with a battery that has nothing wrong with it.
When I replaced the ~ 6 year old battery with a new one, the voltage reading while the same vehicle was running was up to 2 volts higher right after having started the vehicle, and 1 volt or more higher after that.
The car had been misbehaving because the voltage while the car was running was lower than the minimum required for the car's main control circuit board at the circuit board.

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May 11, 2012 at 21:23:46
I was answering this topic but it has disappeared.....

Auto and manual switch off the main power to inverter line

Update - this topic appears to have more or less the same text:
Inverter Switching difference problem

WHY haven't you responded at all to response 5 in this topic ??

A properly working UPS for a computer system DOES NOT Restart the computer when the AC power is lost ! - the computer continues to work.

UPS = Uninterruptible Power Supply
" will provide near-instantaneous protection from input power interruptions, by supplying energy stored in batteries or a flywheel."

Inverter / Home UPS ( Eco Model )
PICI6F676 based design

If that's your inverter model, READ THE MANUAL for it !

Click on the Manual tab on that page.

It has two modes - Inverter mode, and UPS mode !

You must have a jumper on the board set a certain way for the inverter to be in UPS mode.

There's also info in the manual about how you can change something to change the charging rate .

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May 11, 2012 at 22:07:39
Mr. Tubesandwires thanks for respond.
I showed the ups to a service engineer. he told that the transformer did not match the circuit board....and as to change the transformer.
As the same time he is not conforming the problem....and i don't want to waste money(i don't have money) for the transformer without conforming the problem i left the problem and started using computer with the inverter.
once again thanks for your reply...

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