[low_bass_makker]

Anyone here used NorthStar batteries ???

They have three series. Red, Silver and Blue. Red for stable grid conditions, Silver for Stable to semi stable conditions and Blue for unstable conditions.

Any pointers or some one using them ???

[carboy]

I have a Microtek 800 VA sine wave inverter (Model 800EB) with Exide IN1500 150A battery. Both are around 4 years old. I bought it when I was in Pune. I think the battery is on it's last legs and I would need to replace it soon. Now in Bombay, power cuts are not frequent, so I want to go for a lesser capacity battery - what's the lowest I can go for (typically I want to run 2 fan, 2 tubes and a 155 W TV) - I think a 80 AH battery should be good enough for a 2 hour backup. Are batteries available in 80 AH capacity & what do they cost?

If I was under proper Bombay electrical supply, I would junked the inverter. But Mulund is under MSEDCL (maharashtra electric supply rather than Bombay), so the occasional power cuts do happen.

Originally Posted by Aroy

The inverter consumes quite a lot of power, most of it at stand by, that is when there is power and the battery is full, but the inverter keeps the battery at a slow charge.

. Normal over all efficiency of an inverter is 80%, so you are loosing 20% power.

. The standby current in an 800VA unit can be as high as 0.5A, so you are loosing 1/8 (KW)*24(Hours)*30(days) = 720/8 ~ 70 units per month

Does the power consumed because of the inverter depend only on the inverter rating or also the battery capacity connected to it?
Also, let's say you are going on vacation - what do you do to switch off the charging. There is an on/off switch on the inverter & there is also a on/off switch on the wall (fixed by the installer) - which is the one to switch off?

[Aroy]

Originally Posted by carboy

Does the power consumed because of the inverter depend only on the inverter rating or also the battery capacity connected to it?
Also, let's say you are going on vacation - what do you do to switch off the charging. There is an on/off switch on the inverter & there is also a on/off switch on the wall (fixed by the installer) - which is the one to switch off?

There are threeo parts to it.
1. The power consumed by the Inverter under no load. This is the power required to run its controller. Can be as low as 50W and as high as 150W.
2. The efficiency of the Inverter under low load. The efficiency approaches 80%+ at full charging load, but tapers off to low 20's under low load.
3. The self discharge of the battery. The higher it is, the more charge it will loose and hence more the inverter has to charge it to top up.

So in effect if you are not going to use the Inverter for some time, you are using up between 50W and 200W for just keeping it on stand by. Best to
. Switch the inverter off.
. Disconnect it from mains.
. Ideally you should also disconnect the battery terminals, so that no current leaks from the battery into the Inverter circuits.

Regarding the minimum battery size. The smallest I have seen in an 800VA Inverter is 80AH. But remember that 80AH capacity is for 20 hours discharge rate. for a 1 hour discharge rate the capacity is derated to about 30AH. What this means is that
. for 20 hours you can have 4A discharge = 4 x 20 x 12 = 1200VA
. for 1 hour you can have 30A discharge = 30 * 1 * 12 = 360VA

[carboy]

Originally Posted by Aroy

. Ideally you should also disconnect the battery terminals, so that no current leaks from the battery into the Inverter circuits.

Does this happen normally? And what are the repurcussions?

Originally Posted by Aroy

Regarding the minimum battery size. The smallest I have seen in an 800VA Inverter is 80AH. But remember that 80AH capacity is for 20 hours discharge rate. for a 1 hour discharge rate the capacity is derated to about 30AH. What this means is that
. for 20 hours you can have 4A discharge = 4 x 20 x 12 = 1200VA
. for 1 hour you can have 30A discharge = 30 * 1 * 12 = 360VA

I really didn't understand this at all!! Can you explain this again for a layman?

[Aroy]

Originally Posted by carboy

Does this happen normally? And what are the repurcussions?

I really didn't understand this at all!! Can you explain this again for a layman?

1. Whenever any circuit is connected to a power source (battery here), the circuit consumes power. So if the battery is connected, the inverter will consume some power (how ever little), draining the battery over time. This can avoided by isolating the battery - switch or disconnect the terminals.

2. When you have a capacity rating of a battery, that capacity is in Ampere-Hour : current x time. The rating is either at 20 hour, 10 hour, 5 hour or 1 hour discharge rate. The capacity reduces as the total discharge time reduces. For example :
. 80AH capacity is for 20 hours discharge, that is 4A/hour for 20 hours
. 30AH capacity is for 1 hour discharge, that is 30A/hour for 1 hour.

The ratio of 30AH and 80AH is the derating factor, which in this example is 30/80 = 0.375 or 37.5%. Depending on battery design the derating factor for 1 hour duty, can vary from 50% to 5% of the full theoretical hour capacity.

I hope I have been able to explain this properly.

What is important to note is that when you calculate the time your inverter can give you power, you have to incorporate
1. Efficiency of the inverter, converting DC to AC, where you can safely assume 80%.
2. Derating factor for the time the inverter will deliver power. For normal home use where power is required for maximum 5 hours, a derating of 50% suffices. For large installations, without generator back up you design for 10 hours of backup, so derating will be 80%. For computer UPS where 1/2 hour time suffices, a derating of 70% may be required.

Also note the maximum battery life for lead acid batteries is at the rated 20 hour discharge rate. The higher discharge rate the shorter the battery life.

[cooljai]

Checked with a couple of dealers in Bangalore and none of them are supplying Exide IT500's. They say its in short supply as the stocks are getting diverted to Chennai/TN.
Is there someone here who knows a reliable supplier in Bangalore (Near Kammanahalli) who can give a good price for the battery as well as the inverter (Preferably APC)?

[anujmishra]

Originally Posted by cooljai

Is there someone here who knows a reliable supplier in Bangalore (Near Kammanahalli) who can give a good price for the battery as well as the inverter (Preferably APC)?

APC is worst inverter in my terms and way expensive. Till recently they were selling Square Wave inverter for the price more than Sukam Sine Wave inverter.

Why are you so inclined towards APC? There are other very good brands like Sukam, Microtek, TruePower, VGuard etc.

Regarding battery, I would not advice you to go to Exide. These Exides are prone to early failure. You can find Amaron, Amco, Sukam battery etc. for longer and trouble free life. My 2 cents. Decision is in your hand.

[gopikb]

Originally Posted by anujmishra

Why are you so inclined towards APC? There are other very good brands like Sukam, Microtek, TruePower

I can second that. I have been using a sukam 800VA inverter since the last 7 years and it has been serving us well. For battery i have exide inva tubular battery which comes with 5 year warranty. Been ok since the last 3 years

[esteem_lover]

Guys, I have been quoted the following, please let me know

APC 850VA - Rs.7,500
AMCO 180 Ah - Rs.14,500 (2 years replacement warranty + 1 year service warranty)

Total, after a small discount - Rs. 21.5k. Is this a fair deal ? We have 10-12 hour power cuts everyday.

[cooljai]

@esteem_lover
If its APC BI850Sine, your quote seems to be on the higher side.
I had quotes starting from 5800 to 6500.

[geeash]

Guys what's the difference between exide Invatubular and invared battery. It500 is out of stock in chennai. My dealer is suggesting invared 150ah saying only difference is warranty my batteries died out I want to get one as soon as possible. Can someone help me

[aks_karthik]

Yesterday I have installed Inverter in my house.

Inverter : Sukam Falcon 800VA/12V(2 Years Warranty) - Home Solutions | UPS - Pure Sine Wave | Falcon
Battery : Base Tuff Tubular BT 15000 (2+2 Years Warranty) - http://basebatteries.com/Product-Des...Tuff (Tubular)

I have bought it from my friend who is the dealer, So i got the whole things for 17K including Transport and Electrician.

[racer_m]

Originally Posted by aks_karthik

Yesterday I have installed Inverter in my house.

Inverter : Sukam Falcon 800VA/12V(2 Years Warranty) - Home Solutions | UPS - Pure Sine Wave | Falcon
Battery : Base Tuff Tubular BT 15000 (2+2 Years Warranty) - http://basebatteries.com/Product-Des...Tuff (Tubular)

I have bought it from my friend who is the dealer, So i got the whole things for 17K including Transport and Electrician.

I got a quote of 14K all inclusive with fitting for
Sukam Shiny 650VA/12V(2 yrs warranty)
Sukam Conquerer 1500BT Tubular (150AH) battery (48 months Warranty)

Want to know if Sukam Batteries are good or should I choose Exide, Base or Amaron?

[aks_karthik]

Originally Posted by racer_m

I got a quote of 14K all inclusive with fitting for
Sukam Shiny 650VA/12V(2 yrs warranty)
Sukam Conquerer 1500BT Tubular (150AH) battery (48 months Warranty)

Want to know if Sukam Batteries are good or should I choose Exide, Base or Amaron?

I don't think, there's a big difference with Battery provided some extra care and service monthly.
BUt heard Exide is good for Inverters but too costly compare to other brands.

[moralfibre]

Has anyone here used Autobat batteries? I have never heard of this Made in Pune brand. All inverter dealers I called so far are swearing by it. They have a 2 year free replacement warranty and a +3 year prorata replacement warranty with the battery.
I am happy with brands like Exide / Amaron, etc.