I need some help buiding voltage controlled switch of solar panel of trucks battery charger. I have come up with schematic, but i have hard time figuring up what to use as control switch. The solar panel must continually provide power to batteries so our controlled switched should be able to turn on and off.

Oussou!

 

I know I can use Op-Amplifier as comparator, but I'm not sure if PNP will be good as controller because we need 250Am.

 

I have come up with schematic,

It will help if you post your schematic.

Ken

 

I mean i have some idea that using LM311 as comparator will work as industry standard, but i'm not sure what to use as controller! My schematic is nothing more than Op-Am
Any idea Ken?
Thank you!

 

So, what is it exactly that you want to do?

Disconnect the solar panel when there isn't enough sunlight to charge the battery?

Disconnect/dump the solar panel when the battery is charged enough?

 

I want to switch off the solar panel when battery is fully charge. The controlled switch must also be able to be turn on when battery is idle at night time.
Thank you!

 

I want to switch off the solar panel when battery is fully charged.

OK. Usually the way that is handled is either the charge voltage is "clamped" to a certain level, the panel is altogether disconnected from the battery, and/or the solar panel output is "dumped" to ground.

The controlled switch must also be able to be turn on when battery is idle at night time.

I don't understand what you are attempting to convey.

 

So, what is it exactly that you want to do?

Disconnect the solar panel when there isn't enough sunlight to charge the battery?

Disconnect/dump the solar panel when the battery is charged enough?

I want a solar to be swicth off when there isn't enough sunlight to charge battery.
Thank you
Oussou!

 

OK.

What is the maximum voltage and current rating of the solar panel? This needs to be known.

 

In the simplest system a diode is used so that current doesn't flow back through the cell at night. You lose 0.7V but it's nice and easy.

 

OK.

What is the maximum voltage and current rating of the solar panel? This needs to be known.

The maximum voltage is 18 given solar panel can hardly goes beyon that and the maximum current is 250Am.

Thank you!

 

maximum current is 250Am

Did you mean 250mA? If not, Ive gotta get me some of your panels.