solar panel with 14V with 28cell

[ckchok]

HI, I am Chok here from malaysia. I have recently order some solarpanel range from 100wp to 10wp with 28cell which will produce 14Vmp. I would like to have some ideal either this panel can charge a solar gel battery with capacity 10ah to 100ah ?

The ideal is because of the weather in malaysia is always hot through out the year, so the battery doesn't required much voltage to charge during the cold weather. And also i am trying not to use MPPT charge controller as mosst of the MPPT charge controller starting doing the job when the voltage up about 15V, can someone correct me!

Thank you!

[Sunking]

Hope you are planning on charging 8 volt batteries.

[ckchok]

Hope you are planning on charging 8 volt batteries.

Oh No! Mr.Sunking... could you explain this more to me!!!! i can't even can charge the battery to a certain percentage ??

[Mike90250]

A 12V battery, needs about 16V (applied to the battery, from the charge controller) to completely charge. With losses in the controller, you need at least18V from the solar panel, and that is subject to "droop" in hot weather, so many panels are made for 19-21V for 12V battery applications.

Less than fully charging the battery, will quickly ruin it from Sulfation.

[Sunking]

Mike explained it, you need 36 cells.

[ckchok]

A 12V battery, needs about 16V (applied to the battery, from the charge controller) to completely charge. With losses in the controller, you need at least18V from the solar panel, and that is subject to "droop" in hot weather, so many panels are made for 19-21V for 12V battery applications.

Less than fully charging the battery, will quickly ruin it from Sulfation.

Thank you very much Mr.Mike.

[ckchok]

Mike explained it, you need 36 cells.

Mr.Sunking, thanks for your help!!

[ckchok]

Mr.Sunking, thanks for your help!!

As for Battery.. which type of battery is generally working well in a hot country. SLA AGM or Gel type?

[Sunking]

As for Battery.. which type of battery is generally working well in a hot country. SLA AGM or Gel type?

I would go with FLA

[ckchok]

Solar Panel Grounding

I would go with FLA

Dear,

My simple solar system is as below :

1. Solar PV Panel +/- to Charge controller (PV +/-)
2. Charge Controller (Batt +/-) to Battery bank (12V)
3. Battery to DC12v Car Player and DC/AC Inverter (12V/AC240V - 500W modified sine wave).
4. The Inverter load is mainly AC 240V 18w Energy Saving Light

The circuit is tested and running well but when i touch the battery terminal or the casing for car player and inverter, i found that the electric shock is strong, it seems like AC current flowing around my system

I would like to know , it is i need to ground the system. If yes, how do i ground it ? from battery terminal or the inverter casing ?

Thank you!

[Mike90250]

With mod sine inverters, you cannot ground them, as they generate 55 (or 110) VAC from either side of the battery potential . There should be an instruction sheet with your inverter that may say if you can ground the - battery terminal. But generally they have no transformer, and are subject to shocks when something in the system is damaged. Bummer.

[ckchok]

With mod sine inverters, you cannot ground them, as they generate 55 (or 110) VAC from either side of the battery potential . There should be an instruction sheet with your inverter that may say if you can ground the - battery terminal. But generally they have no transformer, and are subject to shocks when something in the system is damaged. Bummer.

Ok Thanks Mr.Mike,

If in this case, i planning to replace the inverter to Pure Sine Wave, once i replace can i just simply ground the body of the inverter ?

[Mike90250]

I know for a fact, that the Morningstar SureSine 300 (600W for 10 min) inverter can be grounded. It needs to be wired to both the battery, and to an outlet, it has no built-in outlet. But it does have a ground terminal, but you won't find it a a local outlet store generally, you will have to order it from a supplier. It's also the best small inverter I've found.

Mike

[ckchok]

I know for a fact, that the Morningstar SureSine 300 (600W for 10 min) inverter can be grounded. It needs to be wired to both the battery, and to an outlet, it has no built-in outlet. But it does have a ground terminal, but you won't find it a a local outlet store generally, you will have to order it from a supplier. It's also the best small inverter I've found.

Mike

Tks Mr.Mike,

The instruction manual for these modified sine wave didn't tell the grounding issue. So, for the time being, can i ground the system in both the positive and negative leg at the battery, or just positive leg ?

[Mike90250]

No grounding on mod sine inverters

if you ground + & - on the battery, you create a dangerous short circuit.

Often, the battery - is connected to ground in a car, and a mod sine inverter works there, but there is a good reason the manuals for mod sine inverters don't mention grounding, it will blow something up.

But getting shocks is not normal, even with mod sine.