[Sebring]

Is it a good idea to have both Invertor and generator for home? Is the Generator fuel petrol or Diesel?

[HillMan]

Originally Posted by Sebring

Is it a good idea to have both Invertor and generator for home? Is the Generator fuel petrol or Diesel?

That's an over kill

Popular generators have Kerosene and Diesel. Kerosene ones use petrol to startup.

I'll recommend Su-kam home invertors with Exide tubular battery.

[Aroy]

Originally Posted by Sebring

Is it a good idea to have both Invertor and generator for home? Is the Generator fuel petrol or Diesel?

It depends on the quantum of power cuts. Here are the scenarios

1. If you have a heavy load, say > 3KVA, and the power goes for at least 2 hours at a time then generator is the way to go

2. If you have light load, say < 1KVA and the power does not go for more than 4 hours per day, then inverter is the way to go.

3. This is the toughest case. You have equipment which is critical and even a second of power loss is detrimental (Medical Equipment, Exchanges, Transmitters or just your large entertainment system) then you need sine wave inverters for continuous power and a generator to back it up if the power requirement is large or the cuts longer. Here the primary power back up is the online inverter and the secondary a generator. The inverter will be as large as the total power required - 1,2 .... 100KVA, but the batteries will be sized for 1/2 hour or less, enough time to start the generator.

[coolclouds]

I am looking for an inverter/UPS for home use. It should connect 2 laptops and router ideally with two hours back up. How many AH battery/VA required?

No need to connect other appliances.

Thanks in advance.

[Abes]

Originally Posted by coolclouds

I am looking for an inverter/UPS for home use. It should connect 2 laptops and router ideally with two hours back up. How many AH battery/VA required?

No need to connect other appliances.

Thanks in advance.

Assuming that the laptops are 120W each & the router as 10W, total load is 250W.

Assuming a 0.7 power factor, 360VA inverter would be enough. Go in for the next available size.

For 2 hrs backup, assuming a 25% inverter + battery losses, the WHr required is 625

625Whr ÷ 12V = 52Ah, thats the minimum battery capacity.
Go in for the next available battery capacity, assuming my calculation is right.

Its always a good thing to go in for a capacity considering future requirements & extended black outs.

The laptops does have their own batteries, which should be giving at least 3 hrs backup when new.

[Aroy]

Originally Posted by Abes

Assuming that the laptops are 120W each & the router as 10W, total load is 250W.

Assuming a 0.7 power factor, 360VA inverter would be enough. Go in for the next available size.

For 2 hrs backup, assuming a 25% inverter + battery losses, the WHr required is 625

625Whr ÷ 12V = 52Ah, thats the minimum battery capacity.
Go in for the next available battery capacity, assuming my calculation is right.

Its always a good thing to go in for a capacity considering future requirements & extended black outs.

The laptops does have their own batteries, which should be giving at least 3 hrs backup when new.

Be careful while calculating battery capacity. Normally the capacity decreases with shorter discharge times :

1. Full capacity at 10H discharge
2. 1/2 capacity at 5H discharge
3. 1/4 capacity for 1H discharge.

So for 2 hours use a battery which is at least 3 times the AH required.

[HillMan]

Originally Posted by coolclouds

I am looking for an inverter/UPS for home use. It should connect 2 laptops and router ideally with two hours back up. How many AH battery/VA required?

No need to connect other appliances.

Thanks in advance.

If router is the only appliance connecting into the UPS. Here is an inexpensive solution.

I'll recommend to go with the 600VA UPS that claim around 20mins backup for desktop computers. These cost around 2.5K

It can run a wireless router easily for 2-3hours. It will also save from disconnects due to power fluctuation.

However, you will need battery replacement every 3years. Around Rs.600/- in exchange of old battery.

If you want to connect the laptop as well, then go for a 600VA unit that use wet battery. IMO; Su-Kam is a good choice, you can connect a tube light and fan as well for comfort. Will cost you around 10K.

Here is a good article for capacity planning;
http://www.electroschematics.com/573...up-some-facts/

[audioholic]

Request some help for a generator related issue:

Generator in consideration - Kirloskar Green power- 30kVA - Water cooled - Manual control
Hours run - ~200
Age - 4yrs

We called up an independent service person to just come and take a look at the generator and check if there was any repairs needed just in case. As I told, there was no other problem and we were interested in routine maintenance.

This chap turns up, and calls up me and another owner(we dont have an association) and informs that the ESU(Engine safety Unit) had to be replaced and it would cost 4.5k for the same. He warned that the generator would be damaged if we didnt do so. Being a petrol head , I did not buy this argument and asked him how and why he thinks it should be changed. He gave me lame reasons, that the unit would have been spoilt due to excess cranking, or water entering the circuit, and so on. I put the issue on hold and checked the gen myself. He had disconnected the connection to the fuel solenoid and left it like that. He even informed the security to shut down the generator by moving a lever instead of the key and told it would benefit.

Since he didnt give a proper explanation, I want to know how we should diagnose the issue with the ESU, if any. The generator starts and runs as usual, does not overheat, takes load without problem. Upon all that, it has rarely been used. No indications on the display too. Should I believe his theory?


Our area rarely faces an electrical shutdown. Apart from a minute or two of power cut during the day, we have never witnessed a shutdown from months. Hence, the generator was very very sparingly used. It was being started once in a while just to keep the whole unit primed and the batteries charged.

A few weeks back the security guards were shuffled and the new guy had never started the gen. Suddenly we faced a power cut and the generator failed to crank. The battery seemed to have lost its juice over prolonged non usage. There is this piston which needs to be manually pumped in case the generator doesnt start and we did that. After that, the generator came to life. However it took a while before the battery regained its charge. After shutting down, it wouldnt restart so we jumpstarted the engine and let it run for an hour. The battery was fully charged then and the generator would run as usual.

I just want to ensure that nothing is really wrong and take that person to task. Have contacted the authorized service personnel and will let them check too. But I dont want to get ripped off unnecessarily.

[Aroy]

Originally Posted by audioholic

Request some help for a generator related issue:

Generator in consideration - Kirloskar Green power- 30kVA - Water cooled - Manual control
Hours run - ~200
Age - 4yrs

We called up an independent service person to just come and take a look at the generator and check if there was any repairs needed just in case. As I told, there was no other problem and we were interested in routine maintenance.

This chap turns up, and calls up me and another owner(we dont have an association) and informs that the ESU(Engine safety Unit) had to be replaced and it would cost 4.5k for the same. He warned that the generator would be damaged if we didnt do so. Being a petrol head , I did not buy this argument and asked him how and why he thinks it should be changed. He gave me lame reasons, that the unit would have been spoilt due to excess cranking, or water entering the circuit, and so on. I put the issue on hold and checked the gen myself. He had disconnected the connection to the fuel solenoid and left it like that. He even informed the security to shut down the generator by moving a lever instead of the key and told it would benefit.

Since he didnt give a proper explanation, I want to know how we should diagnose the issue with the ESU, if any. The generator starts and runs as usual, does not overheat, takes load without problem. Upon all that, it has rarely been used. No indications on the display too. Should I believe his theory?


Our area rarely faces an electrical shutdown. Apart from a minute or two of power cut during the day, we have never witnessed a shutdown from months. Hence, the generator was very very sparingly used. It was being started once in a while just to keep the whole unit primed and the batteries charged.

A few weeks back the security guards were shuffled and the new guy had never started the gen. Suddenly we faced a power cut and the generator failed to crank. The battery seemed to have lost its juice over prolonged non usage. There is this piston which needs to be manually pumped in case the generator doesnt start and we did that. After that, the generator came to life. However it took a while before the battery regained its charge. After shutting down, it wouldnt restart so we jumpstarted the engine and let it run for an hour. The battery was fully charged then and the generator would run as usual.

I just want to ensure that nothing is really wrong and take that person to task. Have contacted the authorized service personnel and will let them check too. But I dont want to get ripped off unnecessarily.

It is best to ask the authorised service. From what I know, a generator has a maintenance schedule based on hours of usage and the number of starts. This data is available from the generator manufacturer.

In case your battery runs down, why not invest in a battery charger. It would cost less than 1K and save on fuel you use for charging the battery. Any battery shop would be able to advise you on the charger required.

[audioholic]

Originally Posted by Aroy

It is best to ask the authorised service. From what I know, a generator has a maintenance schedule based on hours of usage and the number of starts. This data is available from the generator manufacturer.

In case your battery runs down, why not invest in a battery charger. It would cost less than 1K and save on fuel you use for charging the battery. Any battery shop would be able to advise you on the charger required.

Thanks for the idea. Will check with the shop for a battery charger.

The generator has always been maintained as per schedule, whether used or not, every six months.

[anupmathur]

Originally Posted by audioholic

.....
Since he didnt give a proper explanation, I want to know how we should diagnose the issue with the ESU, if any. ....

I very much doubt there is a problem with the so-called ESU.
There is really no way that you can check it except by actually creating a situation that it is designed to protect against and seeing whether it works! Too risky for anyone other than qualified maintenance crew to do this test.

These units are usually designed to protect against one or all of the following faults: Low oil pressure, high coolant temperature and last, very important, engine over speed condition.

Aroy has already suggested the best solution to keep the batteries charged. Buy a trickle charger.

[Simhi]

Friends, help me decide which brand and model of inverter to buy in Pune

I am looking for new inverter (not battery as the current Exide IN1350 Plus - 135AH is working fine for the last 3 years).
I talked to few people/dealers and have short-listed following brands
1. APC
2. Luminous
3. Sukam
4. Genus

I am looking for a full sine wave inverter in the range of 850 to 900VA.
One of the main criteria would be service backup in Pune (one of the reasons Microtek did not make to the list - bad experience faced by a friend)

Also, please let me know if you are aware of genuine dealers.

[diyguy]

Been using APC about 7+ years. I have two. One is a square wave and the other is a sine wave (2 years old). Service has been good when I needed it. They also gave me a replacement for my square wave about 4 years ago with a two year AMC costing 3500rs. I would blindly go with APC anyday and do recommend my friends to purchase this brand too. I have a couple of PC UPS from APC too.

[Simhi]

Thanks diyguy. I would have preferred to go with APC. But poor response from the company. No reply to email queries or submission of form on their site. Also, the dealer information on their site for Pune seems to be wrong. Also, did not find many dealers backing it. Finally after talking to multiple dealers settled for Su-kam 850VA Pure Sine wave Shiny model. Multiple Exide dealers seems to be dealer to Su-kam. Not sure if Exide and Su-kam have any tie-ups. Anyways, let's see how this model performs. The model has a UPS mode in which it works as PC UPS. I am yet to test the functionality though.

[null]

Exide has its own range of inverters now (for last 2 years I hear) and have read a few +ve reviews about them. Why not include them into the list as it has a UPS mode/normal mode(almost all home UPS/Inverters have it nowadays). May be your battery supplier can assist in procuring the inverter as well?
Link: http://www.exidereachout.com/product...-home-ups.aspx