Planing to install a budget solar panel system at my home

[rahulkp1986]

hello friends
Here i have my MPPT+Solar panel+ battery+Sine wave inverter.
Im planing to connect my solar panel to the MPPT and the battery is charged by the MPPT. Now my planing is that, when ever there is enough sun light I need to run my house in solar panel. and the system switches to my grid when the battery charge goes below 60%. and this remaining charge can be used to deal any blackout happening in the night.

so in this method, i should connect my inverter directly to my battery. and the charging circuit in the inverter is deactivated, so that there is no charging from the grid. now i need my MPPT to activate a relay which disconnects the grid supply to my inverter and inverter runs on solar when the battery charge is above 60%. things go good till here. Here comes my doubts.

As i have gone through some MPPT.. it has a stable current, so when i switch to solar system, my home uses around 500W, and needs around 20 A for inverting (24V system) I have installed a 1000W panel system which can give 30 A but since the charging current to battery is very low.. my battery would run out very fast

Other method is to connect my inverter to MPPT load side. but at this time, i need two inverters in my home, one for solar and one for grid black outs

is there any method so that i can have the setup with one one inverter ?

[inetdog]

Your inverter(s) need to be connected directly (via a fuse, of course) to the battery. Do not use the LOAD terminals of a CC, since they are intended for very small loads only.

Your problem is more complicated because your inverter is also a charger.

[Raul]

Have a look at filax( transfer switch)
They made by victron .

[rahulkp1986]

Your inverter(s) need to be connected directly (via a fuse, of course) to the battery. Do not use the LOAD terminals of a CC, since they are intended for very small loads only.

Your problem is more complicated because your inverter is also a charger.

but im disabling charging from my inverter, main objective is to make use of the solar power ..

[rahulkp1986]

[QUOTE=inetdog;164170]Your inverter(s) need to be connected directly (via a fuse, of course) to the battery. Do not use the LOAD terminals of a CC, since they are intended for very small loads only.

ok So consider that i connected my inverter directly to my battery and its a bright sunny day, so my home will run on solar pannel, but the MPPT will only provide the carging current to the battery? and my battery might drain off very fas right?

[inetdog]

Your inverter(s) need to be connected directly (via a fuse, of course) to the battery. Do not use the LOAD terminals of a CC, since they are intended for very small loads only.

ok So consider that i connected my inverter directly to my battery and its a bright sunny day, so my home will run on solar pannel, but the MPPT will only provide the carging current to the battery? and my battery might drain off very fas right?

The current from the MPPT charger will go to the battery and to the inverter input. If the MPPT produces more current than is going to the inverter, the batteries charge.
If the MPPT produces less current than the inverter is taking, the difference comes from the batteries. Which individual electrons end up on which path is not really relevant.

It only gets complicated when you have both Grid power and PV power and are trying to allocate their use in a particular way.

[rahulkp1986]

The current from the MPPT charger will go to the battery and to the inverter input. If the MPPT produces more current than is going to the inverter, the batteries charge.
If the MPPT produces less current than the inverter is taking, the difference comes from the batteries. Which individual electrons end up on which path is not really relevant.

It only gets complicated when you have both Grid power and PV power and are trying to allocate their use in a particular way.

this was a great reply, thanks for the reply
Now regarding the design. MPPT in ebay says 10A,20A,40A ets..and it has 3 terminals,
1) Solar panel input
2) Battery charging
3) Load

where does this 10/20/40 ampere implies? on the load terminal? or on the battery charging terminal? bcoz the load terminal has nothing to do with inverter b coz we are connecting inverter to battery

im planing to install 250W pannel and my load is only 150W so i guess, when there is enough solar power i can run my home and charge battery
so if i buy 40A MPPT, the MPPT will deliver 40A from sollar panel to my battery.. am i right?

[Naptown]

this was a great reply, thanks for the reply
Now regarding the design. MPPT in ebay says 10A,20A,40A ets..and it has 3 terminals,
1) Solar panel input
2) Battery charging
3) Load

where does this 10/20/40 ampere implies? on the load terminal? or on the battery charging terminal? bcoz the load terminal has nothing to do with inverter b coz we are connecting inverter to battery

im planing to install 250W pannel and my load is only 150W so i guess, when there is enough solar power i can run my home and charge battery
so if i buy 40A MPPT, the MPPT will deliver 40A from sollar panel to my battery.. am i right?

It will only deliver 40 amps if the panel(s) are producing that much
A 250 watt panel into a 12 volt battery will at best provide 20 amps. Assuming that is a true mppt controller.