Home Inverter Consuming too much power

T

timepass

Beginner
Hello,
Around 1 year back, My total electricity consumption per month was 4 to 4.5 units per day.
Somehow, it increased to 6.5 to 7 units per day over the last 6 months without any new electric fitments or uses.
So I got into trial & error checks by keeping 1 appliance off each day and observing.

I observed that my 600 VA inverter (Su-kam brand, mfg year 2010, installed in 2011, so now serving since 14 yrs) connected to a Exide tubular battery (6-7 yrs old) was suspicious.
Inverter setting is at INV (not UPS), Normal Charge NC (not HC).

We rarely have power cuts at my place, so battery power is rarely used. It is connected to 2 fans, 2 LED tubelights (18w), 2 LED bulbs (9W) & a Desktop PC (CUPU & monitor). During power cuts, maximum only Desktop PC + 2 fans + 1 LED tube is used. That too very very rarely.

I observed that even though main supply power was there, the inverter's fan was turning on & off frequently. (Now, I don't know if it is normal for inverter's fan to run like this, but I observed it recently so mentioning. Inverter is placed in a small almirah at the top, so I never observed it regularly in the past.)

I disconnected both battery & inverter completely, & kept them aside exactly for 48 hrs (2 full days - 10AM to 10 AM).
At the time of immediately after disconnect, Battery terminals was showing 13.25 Volts (checked using digital multimeter) .
After 24 hrs., they were showing similar 13.23 Volts.
After another 24 hrs (total 48 hrs of disconnect), they were still at 13.23V. So battery does not seems to be a problem.

During 48 hrs, using sand paper I cleaned up the copper lugs at the end of red & black wires coming out of inverter & which connect to positive & negative of battery, and they turned bright & shiny.
I also opened the inverter cover, & checked for any loose wire connections & everything was found to be intact.

Interestingly, during these 48 hrs with battery-inverter disconnected, the total electricity unit consumption was back to 4.5 units per day.

After 48 hrs, I connected back the whole inverter & battery setup.
Immediately after connection:
- The battery terminals were reading 14.3 Volts.
- The inverter fan keep stopping & running randomly, even when the main power supply was there.
- The power consumption is now back to 6.5 - 7 units per day (with no power cuts, so battery supply was not used at all)

My questions, if any experienced experts can help

1) Generally, with no power cuts, how many units will the inverter setup (above configuration) usually consume per day?
2) Is it normal to have 2 - 2.5 units consumed by inverter setup (with no power cuts) or is it abnormally high?
3) If it is high, then is my inverter a problem? Is the battery a problem? Or both?
3) Any other checks that I can perform to confirm the extra 2-2.5 units per day consumption?

Thanks
 
Can you test your battery capacity? Is it running as long as it is supposed to? When you attach a load to it (as in have something running off the battery) what is the voltage? See if that drops a lot compared to idle.
Charging float voltage is 13.5v. Maybe your battery is going bad and your inverter is turning on once in a while to charge it back up.
 
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karanwk said:
Can you test your battery capacity? Is it running as long as it is supposed to? When you attach a load to it (as in have something running off the battery) what is the voltage? See if that drops a lot compared to idle.
Charging float voltage is 13.5v. Maybe your battery is going bad and your inverter is turning on once in a while to charge it back up.
Click to expand...
@karanwk - thanks for the response.
Recently, have charged the battery fully. Then turned off main supply to observe how long it works with 2 fans, Desktop PC and 1 LED 18W tubelight.
It ran fine for 2 hrs, which is when I turned on the power supply again. (it means it had capacity to continue beyond those 2 hrs.)
 
The consumption does sound very high.
Does your inverter have a bypass?
Do you have a multimeter with a clamp? If you can check the amps going in vs the amps going out. (math in my head says maybe .4amps on the 220v ac?) Is it a continuous drain or just turns on when the inverter kicks on and off?
Can you also see what the incoming voltage is when the inverter kicks on? maybe there is a voltage fluctuation and so the inverter is disconnecting the mains and kicking on?

Possible issues i can think of:
1)the inverter is charging the battery because its dropping in voltage with time.
2)the inverter is disconnecting the mains and powering off the battery because its either a voltage fluctuation in the incoming power to your house. Or over time, some electronics are gone bad and instead of tripping at say 180v, its tripping at 210v
 
karanwk said:
The consumption does sound very high.
Does your inverter have a bypass?
Do you have a multimeter with a clamp? If you can check the amps going in vs the amps going out. (math in my head says maybe .4amps on the 220v ac?) Is it a continuous drain or just turns on when the inverter kicks on and off?
Can you also see what the incoming voltage is when the inverter kicks on? maybe there is a voltage fluctuation and so the inverter is disconnecting the mains and kicking on?

Possible issues i can think of:
1)the inverter is charging the battery because its dropping in voltage with time.
2)the inverter is disconnecting the mains and powering off the battery because its either a voltage fluctuation in the incoming power to your house. Or over time, some electronics are gone bad and instead of tripping at say 180v, its tripping at 210v
Click to expand...
Thanks again @karanwk.
These are useful insights. Allow me some time to check these and I'll update ASAP.
 
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