Inverter Not Turning On, but supplying power


timepass

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Hello,


My Su-Kam inverter has apparently stopped working. Need some advice on what could be going wrong.

Before going on leaves, I had charged the battery fully, and then disconnected the inverter power connection from the mains. After coming back, I reconnected the power to main line and turned on the inverter.
However, the LED indicator lights on the inverter are not turning on on any signs (charging, inverter, on). The power to inverter connected tubelights and fans is working normal when the mains electricity is available, but as soon as I turn off the mains supply to inverter, they stop working. I also checked the fuse, it is working fine - that is, when I remove the fuse with mains on to the inverter, the tubes and fans stop working and when I put the fuse back, they start working again.

1) Is it a problem with the inverter, or with the battery?

2) Since the indicator lights are also not turning on, seems to be the case of inverter problem. What can I do to perform some basic checks?

3) Since the power is moving from mains via the inverter to the fans and tubes (and the fuse is also fine), is there any issue with inverter supply?

Any help will be greatly appreciated.

Thanks
 
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6pack

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Depends on the type of battery and how old it is. Is it sealed battery? Is it tubular battery?

You should not have disconnected the inverter from the mains since battery will discharge even if it's not connected to anything. Get some battery repair person to check the battery voltage first. If it's not dead, get your inverter checked.
 

timepass

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Hello,

Thanks for the response.

It is a tubular battery. The person who came to check the battery said that it has around 4 Volts remaining and is telling that the battery is dead. Given that he himself is a battery seller, is there anything else that I can check or try to get it working before I give in to the need of costly battery replacement?

Thanks
 
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blr_p

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Before going on leaves, I had charged the battery fully, and then disconnected the inverter power connection from the mains. After coming back, I reconnected the power to main line and turned on the inverter.
How long was it disconnected ? weeks or months
 

puns

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Depends on the type of battery and how old it is. Is it sealed battery? Is it tubular battery?

You should not have disconnected the inverter from the mains since battery will discharge even if it's not connected to anything. Get some battery repair person to check the battery voltage first. If it's not dead, get your inverter checked.
wait, so we are not supposed to shut down inverter from mains if one is away for like a month ?

How old is your battery ? 18 days is less for complete discharge unless we are talking age old one
 

timepass

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wait, so we are not supposed to shut down inverter from mains if one is away for like a month ?



How old is your battery ? 18 days is less for complete discharge unless we are talking age old one
Battery is 135 Ah and around 5 years old. However, it was working perfectly till before going on leaves. Was powering multiple fans and tubes for 3+ hours. So I doubt if it is really dead and that's the whole reason for seeking help.
 

blr_p

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Battery is 135 Ah and around 5 years old. However, it was working perfectly till before going on leaves. Was powering multiple fans and tubes for 3+ hours. So I doubt if it is really dead and that's the whole reason for seeking help.
Lead acid batteries can self-discharge completely any where from a week to a month depending on the age of the battery, the kind of battery and ambient temperature.

That is why its advisable to keep them on the inverter powered on when away as it tops them up.

Let's assume the batteries have discharged if not flat but by a good amount. It does not explain why the inverter won't come on.

I think you need to have the inverter looked at. An internal fuse might have blown for some reason.

You've confirmed the main fuse is working fine.
 

timepass

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Lead acid batteries can self-discharge completely any where from a week to a month depending on the age of the battery, the kind of battery and ambient temperature.

That is why its advisable to keep them on the inverter when away.

Let's assume the batteries have discharged if not flat but by a good amount. It does not explain why the inverter won't come on.

I think you need to have the inverter looked at.
OK, so I should have added this in my previous reply.

I have fully filled up each cell of the battery with distilled water yesterday afternoon, and left it connected with my inverter switch ON (27 hours now). But the inverter LED indicators are not turning ON at all till now.

Around 30 minutes back, my neighbor was kind enough to let me connect my inverter to his working battery, and there my inverter turned on as normal on his working battery. It was charging his battery with mains on to the inverter, and was also supplying power when mains was switched off.

So I assume that leaves the battery as a problem (or am I missing something here?).

Does the turning on of the inverter depends upon the connected battery?

Should I keep the battery on my inverter charging (though my inverter is not turning on with battery connected) and for how long (27 hours gone already)? Any acid replacement needed? Or should I give it to battery charging person?

The issue with giving it to charging person is that they are not reliable.....they always come back with "battery is dead and need replacement" as per the feedback from my society members.
 
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blr_p

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I have fully filled up each cell of the battery with distilled water yesterday afternoon, and left it connected with my inverter switch ON (27 hours now). But the inverter LED indicators are not turning ON at all till now.
When you say fully filled how much was the level before filling ? Generally its better to fill only after battery is fully charged. Otherwise at a lower charge there is chance of overflow.

Around 30 minutes back, my neighbor was kind enough to let me connect my inverter to his working battery, and there my inverter turned on as normal on his working battery. It was charging his battery with mains on to the inverter, and was also supplying power when mains was switched off.
So this is curious. The inverter refuses to power on because the battery level is too low ? i'm not sure why this is happening.

So I assume that leaves the battery as a problem (or am I missing something here?)
Can you get hold of a multi-meter and measure the voltage across the terminals of each battery ?

Should I keep the battery on my inverter charging (though my inverter is not turning on with battery connected) and for how long (27 hours gone already)? Any acid replacement needed? Or should I give it to battery charging person?

The issue with giving it to charging person is that they are not reliable.....they always come back with "battery is dead and need replacement" as per the feedback from my society members.
If the inverter does not power on then is it charging the battery. Do the batteries feel warm to the touch during this charging ?

A five yr battery is nearing its end if its a regular C20 and you've been using it regularly with proper maintenance.

How long have your power cuts been on average. Did the batteries have to work hard during those 5 years.

Which brand are they, how long was the warranty minus the pro-rated stuff
 

timepass

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Thanks again @blr_p for the inputs.

When you say fully filled how much was the level before filling ? Generally its better to fill only after battery is fully charged. Otherwise at a lower charge there is chance of overflow.

So this is curious. The inverter refuses to power on because the battery level is too low ? i'm not sure why this is happening.


Can you get hold of a multi-meter and measure the voltage across the terminals of each battery ?


If the inverter does not power on then is it charging the battery. Do the batteries feel warm to the touch during this charging ?

A five yr battery is nearing its end if its a regular C20 and you've been using it regularly with proper maintenance.

How long have your power cuts been on average. Did the batteries have to work hard during those 5 years.

Which brand are they, how long was the warranty minus the pro-rated stuff
2 cells on the left were full, two in the middle were at 75%, while rest 2 at the right were at 50% water level.

Unfortunately, I dont have a multimeter, but the battery person who visited last told that it was around 4 V.... (I couldnt see that reading so dont know if he is telling it right)

No, there is no observable temperature change/warmth in the battery despite it being connected with inverter switch ON for 27 hours.

Power cuts in my area are infrequent... average 1 hour per week. I'll say battery was used without much hardwork on its part :). Though I have been very regular in topping it up with distilled water every 3-4 weeks over the last 5 years of use.

SF Stanqueen battery....18 months + 18 months pro-rata.
 

blr_p

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2 cells on the left were full, two in the middle were at 75%, while rest 2 at the right were at 50% water level.

Unfortunately, I dont have a multimeter, but the battery person who visited last told that it was around 4 V.... (I couldnt see that reading so dont know if he is telling it right)
That reading isn't right. There are 6 cells.

At full discharge, each cell will be 1.75 V so 6 x 1.75 means 10.5 V when measured across terminals
At full charge, depending on the inverter each cell will be 2.2 - 2.4 V so 6 x means 13 - 14V V when measured across terminals.
Inverters can cut off at lower levels to preserve battery life

A reading of less than 10 V means a failed cell or more

When did this battery guy visit last ?

Getting a present voltage reading will take out a lot of guess work. Given the inverter comes on with your neighbours battery it seems like your battery is on its last legs. The inverter seems fine.


No, there is no observable temperature change/warmth in the battery despite it being connected with inverter switch ON for 27 hours.
Without any voltage or current measurements it seems like the battery isn't accepting a charge.

Power cuts in my area are infrequent... average 1 hour per week. I'll say battery was used without much hardwork on its part :). Though I have been very regular in topping it up with distilled water every 3-4 weeks over the last 5 years of use.

SF Stanqueen battery....18 months + 18 months pro-rata.
It didn't get much of a workout that is why you got good life considering you are two years beyond warranty.
 

timepass

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When did this battery guy visit last ?
Yesterday afternoon.

So, How should I proceed here here?
Should I keep it connected with inverter for few more hours/days? Or give it to the battery charging guy, or go for a replacement?
 

blr_p

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Yesterday afternoon.

So, How should I proceed here here?
Should I keep it connected with inverter for few more hours/days?
No, because ts not clear its getting charged

Or give it to the battery charging guy,
Let the battery guy have a look at it and tell him to show you what the voltage is.

Whether he has a specific kind of charger that could revive the battery in case its voltage is too low

It seems like the inverter refuses to do anything if battery voltage drops below a certain point.

If he can get the battery voltage up then maybe your inverter can maintain the battery for a little longer

You said it still gives good backup, when was the last time the inverter came on and you got to see a 3h back up ?

or go for a replacement?
Hold off on this for now until you get more info.
 

adder

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You need to charge the battery using a 12v lead acid battery charger, once the voltage reaches more then 10.5v ,( it could start with ever lower detection voltage which we don't know), the inverter would detect the battery and should continue to work, albiet with poor battery life since your battery is old.

You could also use a battery cable and connect it to a two wheeler and kick start the engine, which should start chagring the battery, just enough to raise the voltage to above 10.5v. But since you dont have a multimeter nor a charger. Its best to ask a battery dealer to charge the battery.

If the battery is dead you can desulphate the battery but the results are mostly not worth it, considering indian battery dealers poor knowledge on this. They will mostly ask you to go for a new battery.
 
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6pack

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wait, so we are not supposed to shut down inverter from mains if one is away for like a month ?
Yes. Most inverters have an on/off switch or bypass switch on them. That switch was made for this very purpose where people need to go on vacation or for troubleshooting the inverter.

If we put that switch in off position, the inverter just trickle charges the battery and does not give power to connected devices during power failure. When there is normal mains electric supply, it gives power to connected devices.
 

timepass

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Thanks a lot everyone for the inputs over the last few days. I finally had the inverter-battery setup checked with a "borrowed" multimeter. It was showing 4V only. After having it charged by the battery person for more than 14 hours, it still did not bump up the voltage to the required 12+ Volts. In the meantime, connecting another fully charged battery instantly turned on the inverter setup. So looks like the age old battery is really dead and I need to go for a new one.

Now to summarize for the benefit of all (please correct anything if misinterpreted) based on whatever I learnt from this form (and other places):

  • 1) While going on vacation, keep the mains supply to the inverter-battery setup in ON position. However, turn off the inverter switch which will keep the battery charge up-to-the-mark, but will not drain the battery in case of power cuts. (inputs from @6pack)
  • 2) Top-up the battery with distilled water only (no acid or any other material to be used) based on the water level indicators of the cells.
  • 3) Dont let the battery terminals be corroded - keep them lubricated with petroleum jelly or vaseline
  • 4) Lots of videos are available on YouTube showing a dead battery regaining life after adding baking soda or epsum salt (sendha namak). But it is a very dangerous practice. Additionally, even when it does increase the voltage of the dead battery, it lasts only 2-3 months and again gets dead.

In summary, battery-inverter is a deadly combo of electricity, acid and hazardous chemicals. Max one should do is check the voltages and leave it at that.
AVOID playing around and mixing-and-matching based on DIY tips. Better to spend money, then to take risk with your home electricity connections, or your vehicle's power system.

Again, please correct or add-on to any of the points if is deemed incorrect.

Thanks again for all the vital inputs to the concerned members.

PS: one more question @6pack - for a week long vacation, is it better to completely disconnect the inverter cables connecting to the battery terminals? It will leave the battery completely isolated (i.e. connected to nothing), so there will be no chance of charge leakage. Or will the charge still diminish?
 

blr_p

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It was showing 4V only. After having it charged by the battery person for more than 14 hours, it still did not bump up the voltage to the required 12+ Volts.
This is the part that mystifies me. You said you charged the batteries up completely before going on vacation. Batteries were fine they accepted the charge yet a mere 18 days later that terminal voltage dropped to 4V.

Battery is 135 Ah and around 5 years old. However, it was working perfectly till before going on leaves. Was powering multiple fans and tubes for 3+ hours. So I doubt if it is really dead and that's the whole reason for seeking help.
How long ago was it giving you 3h backup ?


In the meantime, connecting another fully charged battery instantly turned on the inverter setup. So looks like the age old battery is really dead and I need to go for a new one.
You can consider tubulars These are taller batteries and will require less frequent topping up. But will cost more. To be frank getting 5 years out of the Stan Queen 450 is not bad.

3) Dont let the battery terminals be corroded - keep them lubricated with petroleum jelly or vaseline
Petroleum jelly, yes.

Vaseline NO! take note 6pack

Why ? there are different kinds of petroleum jelly. The key differentiator is the melting point.

Vaseline melts at body temperature. This means on a battery terminal it will over a period of weeks just melt and flow away so every 6 months you will have to re-apply it. Wrong use case for vaseline.

What you want instead is a petroleum jelly that melts at a higher temperature. This way you apply it and its there for the lifetime of the battery. On your battery terminals and not coating the walls of the battery case.


Melting point around 100 degrees C, no way is this going anywhere, it will be there for years


This dielectric grease has a meting point over 250 degrees C. Maybe over kill and for the price not worth it.


4) Lots of videos are available on YouTube showing a dead battery regaining life after adding baking soda or epsum salt (sendha namak). But it is a very dangerous practice. Additionally, even when it does increase the voltage of the dead battery, it lasts only 2-3 months and again gets dead.
What i've learned out of this post is inverters of the variety bought by the public are very stripped down in terms of functionality. They offer the bare minimum for the princely sum of Rs.5k. If battery voltages are too low the inverter will reject them. A more specialised charger i kinda think could bring the battery back but if you cannot get one then new batteries are on your horizon.

Power cuts in my area are infrequent... average 1 hour per week. I'll say battery was used without much hardwork on its part :). Though I have been very regular in topping it up with distilled water every 3-4 weeks over the last 5 years of use.

SF Stanqueen battery....18 months + 18 months pro-rata.
Let's say your batteries work once a week. So that's 52 times a year.

The stan queen i would estimate is good for any where between 200 - 400 cycles at 80% discharge.

You are around the 250-300 cycle mark. Had you not disconnected the batteries maybe they might have lasted a little longer ? maybe, maybe not

Thing is you've been doing this in the past too and there was no trouble. So as the battery gets older the self-discharge rate increases and once below a certain point a regular inverter will no longer be able to charge it back again.
 
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technofast

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I have a unique problem with the microtek inverter. Off-late when ever there is a voltage drop the power to the inverter gets disconnected and the inverter starts working through battery mode. I have to manually switch off the inverter switch. Once I do this the power supply to the inverter is restored. What might be the problem?
 

blr_p

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2 cells on the left were full, two in the middle were at 75%, while rest 2 at the right were at 50% water level.
Can somebody shed some light here as in what to do to remedy the differential in levels here ?

One terminal is getting hotter and the adjacent cell as well.