[maddy42]

Thanks Bhpians as you guys did help me understand both the technology and the product which would suit my use case. We did make our purchase of a 2kva inverter with 2 tall tubular battery of 150ah 12kv. The generator will be a substitute for emergencies. Its a kirloskar diesel one of 5kv which does its duty. Hopefully coming months should give us a idea of how many hours of generator running was reduced.

The total cost including installation came upto 42k for the system with a trolley. Anyone reading from the kodagu region do let me know if you need help with the name of our installer.

Also with regards to the Solar panel, we have decided to wait it out as our power bill is not too high as we are on the rural line. With solar our lifetime of ROI will probably never be reached solely on our consumption. Bill is usually under 2k.

Maddy

[prithm]

Originally Posted by rdst_1

I came to this conclusion after trying to size a system for my farm where even I would have been running 1.5-2HP motors.

I have water motors ranging from 1 to 2.5 HP in my home. Planning to go for a 3 KVa inverter with 4 120 mAH batteries.

Can they run these motors (any one of them at any given time) while the load on it at that moment will be of 2-3 tubelights and one ceiling fan ?

[rdst_1]

Originally Posted by prithm

I have water motors ranging from 1 to 2.5 HP in my home. Planning to go for a 3 KVa inverter with 4 120 mAH batteries.

Can they run these motors (any one of them at any given time) while the load on it at that moment will be of 2-3 tubelights and one ceiling fan ?

The main question is how long do you need to run these motors.
My 1.5HP motor fills up my 1000L tank in 6-8 minutes.
If one doesn't need to run the motors at least a few hours every day, then it makes no sense to go for an inverter over a generator.

This could be just my opinion, but I feel that the batteries should be utilized fully within the warranty period. Buying expensive deep cycle batteries and then not using them seems to be a waste of money. Buying a cheaper generator (only if an open generator is feasible) and running it as and when necessary seems a better option as they have a much longer life.

As for your question, a 3kVa inverter with 4 120Ah batteries will definitely be able to take the load and run any 1 motor simultaneously.

[Aroy]

Originally Posted by prithm

I have water motors ranging from 1 to 2.5 HP in my home. Planning to go for a 3 KVa inverter with 4 120 mAH batteries.

Can they run these motors (any one of them at any given time) while the load on it at that moment will be of 2-3 tubelights and one ceiling fan ?

If your base load is low - tube lights and refrigerator, then a high capacity inverter will be under utilised, especially if power cuts are less than a few hours at a time. For the cost of 4 x 150AH tubular batteries you can get a fully automatic diesel generator. In such scenarios it is much better to have a small - 5Kva to 7Kva generator for larger loads and a small inverter for normal use. In case of prolonged power cuts you can also use the generator to run the normal load while charging the batteries.

[prithm]

Originally Posted by Aroy

. In such scenarios it is much better to have a small - 5Kva to 7Kva generator for larger loads and a small inverter for normal use.

Originally Posted by rdst_1

The main question is how long do you need to run these motors.
My 1.5HP motor fills up my 1000L tank in 6-8 minutes.
If one doesn't need to run the motors at least a few hours every day, then it makes no sense to go for an inverter over a generator.

Thanks to both of you.

First, I don't have space to keep a generator. Second, it's for my mom & pop. So you know the technical challenge there.

Only one motor will be used to draw & pump water to anytime. Deep discharge cycle is something that might not occur unless otherwise Vardah cyclone decides to return. The political situation in Chennai is worse than ever. Given that summer is at our doorstep, I wanted a long duration backup that can serve it's purpose with least manual intervention.

One question though, how long does it take to fully charge 4 120 mAh batteries ?

Thinking of using 2 200W solar panels (for the space available) as a alternate power source.

[Aroy]

Originally Posted by prithm

Thanks to both of you.

..........
One question though, how long does it take to fully charge 4 120 mAh batteries ?

Thinking of using 2 200W solar panels (for the space available) as a alternate power source.

Charging time depends on the inverter. Batteries are best charged/discharged over a 10 hour period.

Just ensure that you have sufficient inverter capacity to run all the appliances, and not more. Excess capacity, especially where the base load is low will consume a lot of power in standby.

Solar panels are a good investment, especially if you can use the inverter batteries to store the power.

[prithm]

Originally Posted by Aroy

Just ensure that you have sufficient inverter capacity to run all the appliances, and not more.

I m planning for 3.5 kW inverter with support for solar charging too Aroy.

Hope this can support the water motors that I asked earlier about.

[Thad E Ginathom]

Originally Posted by prithm

First, I don't have space to keep a generator. Second, it's for my mom & pop. So you know the technical challenge there.

It looks like you are going to solve your problem without a generator, but just thought I'd mention the Honda EU70is generator. It takes up very little space and is easier to start and stop than a car. It is not what I'd call portable, as, although it is easy to wheel, it is not easy to lift. We bought it to support a 2hp pump, but as a bonus we can power an AC during those May power cuts.

If the EU30 would be power enough... that is quite tiny by comparison.

The political situation in Chennai is worse than ever. Given that summer is at our doorstep, I wanted a long duration backup that can serve it's purpose with least manual intervention.

One-hour power cuts, late morning, seem to be getting regular!

Thinking of using 2 200W solar panels (for the space available) as a alternate power source.

Still wishing for solar... maybe next year!

[prithm]

Originally Posted by Thad E Ginathom

It looks like you are going to solve your problem without a generator, but just thought I'd mention the Honda EU70is generator. ....
One-hour power cuts, late morning, seem to be getting regular!
Still wishing for solar... maybe next year!

True I agree & I did check as a last resort back up solution. The issue that I immediately identified was that to run these small generators you need open space or should be ideally kept in open air to allow exhaust fumes to escape. Though I do have open space, this generator will then be exposed to heat, sun, bugs, snakes.

Given that parents will not be able to do anything to maintain it & worst unable to switch between inverter & gen, I searched for other options & landed with higher capacity inverter. As you said it's already one hour power cut, and it gets only worst as summer approaches.

Since water motor, fridge, fan & Tubelight are the essential ones, I opted to stretch my budget till 3.5 kW. Solar panel is for reducing the dependency on grid & as back up power supply for the worse of the days like what we experienced in December 2016.

Inverter guys told me to go for 4 - 8 panel array, but I can survive with half of that. & Don't need full support. What might take 2-3 hours with full 8 panel array to charge, will take 8 hours. But that's fine given the cost & space requirement.

[Thad E Ginathom]

Originally Posted by prithm

True I agree & I did check as a last resort back up solution. The issue that I immediately identified was that to run these small generators you need open space or should be ideally kept in open air to allow exhaust fumes to escape. Though I do have open space, this generator will then be exposed to heat, sun, bugs, snakes.

Very true. And it is an expensive small thing to keep out in the open.

Ours actually sits in an almost enclosed side passageway. It's exhaust points towards the gate, which I open (and move it closer) when I run the machine. I also taped up the nearby window.

I have told the story of our generator before (perhaps several times!) but the 2hp pump that it was bought to support is our flood-prevention pump. It works so well that we barely get any standing water in the garden at all, let alone water worryingly approaching the house. And, unlike the petrol-powered pump, it requires no attention, checking or fuss. And my wife said, "This is wonderful: but heavy rain means power cuts, so lets protect ourselves against that."

Given that parents will not be able to do anything to maintain it & worst unable to switch between inverter & gen,

It's a single-switch changeover: they probably could. But you have chosen your appropriate solution

I searched for other options & landed with higher capacity inverter. As you said it's already one hour power cut, and it gets only worst as summer approaches.

Since water motor, fridge, fan & Tubelight are the essential ones, I opted to stretch my budget till 3.5 kW. Solar panel is for reducing the dependency on grid & as back up power supply for the worse of the days like what we experienced in December 2016.

If it had not been for what we see as a very real dependency on that pump in extreme weather (so real that my wife even suggested keeping a spare, and it is not cheap!) I would have gone for solar with that generator money. I'd rather have solar power every day than be pouring petrol money into the generator even just when its needed. But we had had that need.

[prithm]

Originally Posted by Thad E Ginathom

Ours actually sits in an almost enclosed side passageway. It's exhaust points towards the gate, which I open (and move it closer) when I run the machine. I also taped up the nearby window.

How do you maintain this Thad ? Like, do you follow any monthly or bimonthly drill to keep the gen running ? I was told by the generator sales team that generators should not be wet stored and have to be used to their full capacity biweekly.

Originally Posted by Thad E Ginathom

It's a single-switch changeover: they probably could. But you have chosen your appropriate solution.

I did not know it was this easy. What is this switch called ? Is it like the phase change turn switch ?

Originally Posted by Thad E Ginathom

I'd rather have solar power every day than be pouring petrol money into the generator even just when its needed. But we had had that need.

Yes. Solar is the only fail back that we have got in our state and abundant. The solar accessories now days are fully compatible with already existing inverter set up, and the only catch is the wattage of panels and space availability to host that array. If you have lot of open space and don't mind keeping big panels with great wiring and plumbing, you can live life worry free during extreme climates. The best part is that we can build custom solutions as per our need since there are multitude of options available now at just click of a button. I need not step out of my house for anything in this regard.

Only problem is the last two or three months of every year (read that as "God Knows What Might Happen This Year" months) when monsoon clouds play havoc. I have never felt so helpless like what I experienced in Dec 2016. Total chaos and absolute abandonment. Corruption and Heartless behavior of failed public machinery. That is when I decided on self sufficiency rather than living on faith.

[Aroy]

Originally Posted by prithm

....

I did not know it was this easy. What is this switch called ? Is it like the phase change turn switch ?

Bare generators are quite inexpensive. What jacks up the cost for small generators is the controls. There are a few options
1. Totally Manual
Bare generator, manual start with a change over switch. You pull a string or a crank to start. Once started use the change over switch to connect the generator to household circuit and at the same time take the mains out. When the mains power comes, use the switch to change over. Manually stop the generator.

2. Semi automatic
Generator with a self starter. You press the starter button to start and then use the change over switch to switch the power source. Rest is same as 1).

3. Fully automatic
Self starter with AMF (automatic mains fail) Panel. The panel detects when the mains fails. Waits for a preset time (usually user settable) and switches the power source and after that starts the generator. When power returns, the AMF again waits for a preset time and switches the source and then switches the generator off.

The only impediment of having a fully automatic solution is the cost.
. A self starter with a battery will add anywhere between 10K and 30K.
. AMF panels add anywhere between 40K and 90K.
. Acoustic enclosure another 10K

When the generator is small, say 5KVA, the bare generator can be as low as 30K, while a 25KVA generator will about 2.5L. So in case of smaller sets the controls cost much more than the basic generator. Though nothing prevent you from having a fully automatic 5KVA generator, but a search of internet pegs the cost above 1.5L.

https://www.indiamart.com/proddetail...050764462.html
https://www.indiamart.com/proddetail...536859391.html
http://www.koelgreen.com/5-kva-125-kva
http://www.dgsets.net/kirloskar-diesel-generators.html

[prithm]

Originally Posted by Aroy

When the generator is small, say 5KVA, the bare generator can be as low as 30K, while a 25KVA generator will about 2.5L. So in case of smaller sets the controls cost much more than the basic generator. Though nothing prevent you from having a fully automatic 5KVA generator, but a search of internet pegs the cost above 1.5L.

So much for tiny puny generator !!! I was considering something like Honda 2.8kVa cause it looked like something that I can trust my parents to operate... but the price.my goodness.

So, what if I get a turn key start up type generator than the autostart ones... are the prices close enough. Are they safe to charge inverter batteries ?

[Thad E Ginathom]

Originally Posted by prithm

How do you maintain this Thad ? Like, do you follow any monthly or bimonthly drill to keep the gen running ? I was told by the generator sales team that generators should not be wet stored and have to be used to their full capacity biweekly.

We were told we should run it once a week. Just like my car may, occasionally, not run for a week or two, I don't think it is a big deal. When I do run it, I run it for 30-60 minutes and give it some load like an AC. It's important not to just start and stop it: just like a car, that would lead to a flat battery. Manual starting is provided, just in case, but I haven't actually tried it and I don't have strong arms!

Otherwise, service annually --- just like a car.

Here are the generator controls. The red thing is the ignition switch, the push button starts the machine.

I did not know it was this easy. What is this switch called ? Is it like the phase change turn switch ?

Here is the changeover switch. This really needs to be set up by a proffessional to ensure that the generator power is absolutely isolated from the EB mains. First, for the safety of the EB guys, we should not be feeding power into their lines when their power is down, second because the generator power is shared across the three phases.

The only thing is that everything is potentially powered. The responsibility to not overload the generator is ours alone. So we have to be a little bit technical. But most people can grasp it in practice, and hey, I don't understand it in much depth!

If we are doing flood work, then I switch off breakers to other pumps, and, of course, I don't run any AC. Even the 2hp pump does not max out the generator, but the starting surge is considerable., and, in a storm it is going on and off regularly as its pit fills.

Convenience machine! Power cut just as we wanted to eat, so we turned it on to run the microwave

[prithm]

Originally Posted by Thad E Ginathom

Here are the generator controls. The red thing is the ignition switch, the push button starts the machine.
....
Here is the changeover switch. This really needs to be set up by a proffessional to ensure that the generator power is absolutely isolated from the EB mains. First, for the safety of the EB guys, we should not be feeding power into their lines when their power is down, second because the generator power is shared across the three phases.
.....
Convenience machine! Power cut just as we wanted to eat, so we turned it on to run the microwave

Thanks a ton Thad. You are my another Yoda Grand Master next to R2D2 in this forum.

Nice pics and it is the same genset that I was talking about earlier with Aroy. Looks pretty neat and small factor is the USP. I have no choice but to construct a small storage area under the stairwell to terrace and house this along with all the 4 batteries. I am really really worried it being outside (even though enclosed).

Let me do this project and will update you one by one as I progress.