Hello all,

I'm new in electronics and i hope to find some help from you.
I'm trying to supply several sensors form photovoltaic panels and I need to limit the current but i don't know the simplest way to do it.
The panels give me a current between 22-38 voltage and power is 400 w this means the current is around 10 amps.
Can I limit the current for a value of 2 or 3 amps ?
If is possible what component should i use or what type of circuit?


PS:I know that the the solar cell should be connected through a battery but this is only in test purpose.

Best regards

 

hi G,
What are the sensor specifications.? Voltage and Current.?
E

 

Hello E,

As I told before it's in purpose test. And I want to use more or less the next ones:


http://es.farnell.com/linear-techno...f/current-sense-amp-200khz-5tsot23/dp/2294764
http://es.farnell.com/linear-technology/ltc2433-1pbf/ic-sm-adc-delta-sigma-16-bit/dp/1330933
http://es.farnell.com/linear-technology/lt1236bcs8-5-pbf/ref-de-tensi-n-serie-shunt-5v/dp/1273434
https://cdn-shop.adafruit.com/datasheets/ina219.pdf
http://www.robotshop.com/en/led-voltage-meter-blue.html
Arduino board.

I'll not put all of them but the idea is that i'll try to have and output of 30V and limiting the current at 2 amps
I'm trying to transform my house in a phone application. ))

My idea is to connect them in parallel before the limiting device (or circuit).

Thanks

 

Can I limit the current for a value of 2 or 3 amps ?
If is possible what component should i use or what type of circuit?

A 3 amp fuse would do it.

 

Yes i know but that i had choose Current/Power monitor to be able to check any time the consumption of current.
I'm looking for another idea that exclude the fuse resistors.

Thanks a lot!

 

hi G,
You can buy modules like this type.
https://www.amazon.co.uk/Digital-Am...0&sr=8-42&keywords=voltage+and+current+module

EDIT:
Or this version
https://www.amazon.co.uk/XCSOURCE-V...ons&keywords=voltage+and+current+module&psc=1

 

Yes it's an idea but you can not set a limiting current!

Thanks E

 

Just curious? Why do you want to limit current?

 

Hi!
Using the photovoltaic panel i'll have for sure a variation of voltage and current. My idea is use the power board that i put it in the link above and use an arduino board (arduino board support i2c comunication). And with all of them i want to see all the variation of the current and limiting of it went a situation of over current or a short circuit appear.
I all most finish my app in Android studio and with this to connect on internet via Ethernet and i want to see all this in my phone.

For me it's an interesting project an i want to finish in this way ))

All the best

 

Hi!
Using the photovoltaic panel i'll have for sure a variation of voltage and current. My idea is use the power board that i put it in the link above and use an arduino board (arduino board support i2c comunication). And with all of them i want to see all the variation of the current and limiting of it went a situation of over current or a short circuit appear.
I all most finish my app in Android studio and with this to connect on internet via Ethernet and i want to see all this in my phone.

For me it's an interesting project an i want to finish in this way ))

All the best

OK! I was curious because many people enquire about limiting current, when there is no need for it.

 

http://www.adelaida.ro/images/detailed/32/om632.jpg

I'm looking for something like this one but one that i can use between 22-38 V and 0 to 10 Amps.
One that i can put it in a PCB board.

Best

 

hi G,
In normal operation, a circuit will only draw the current from the power supply that it requires to operate.

If you want to limit the current drawn in a short circuit condition you need to have preset the 'non destructive' current allowed, by using a current limiter or a current fold back limiter.
So you must know the allowed current limit, what do you expect that to be in your circuits.??

E

 

Hello,

My expectation is to have a limitation at 2.5A
My idea is to limit at 2.2 or 2.5 and if a have a value bigger then 2.5 in the circuit to be able to close it.

Thanks

 

hi,
There are lots of ready made IC's that would be suitable.
https://para.maximintegrated.com/en/search.mvp?fam=cl_usb_sw&hs=1

What you asking for is a 'foldback' current limiter, that will reduce the s/c current to a 'safe' value in short circuit state.
A simple current limiter would not be suitable.

Your application sounds a little unusual, are you expecting sensor failures.?

E

 

If you want to build a voltage regulator with current limiting, consider one based on the TL494 or a similar IC. Design information can be found here.

 

As i told before is only for me and for my experience with electronics.
I find a board that is use in aerospace industry. They use o board to limit the current when they supply a satellite. it's and LCL (latching current limiter).
I was thinking that is what i'll try to use in a small scale. This is the board that inspire me.

 

hi,
There are lots of ready made IC's that would be suitable.
https://para.maximintegrated.com/en/search.mvp?fam=cl_usb_sw&hs=1

What you asking for is a 'foldback' current limiter, that will reduce the s/c current to a 'safe' value in short circuit state.
A simple current limiter would not be suitable.

Your application sounds a little unusual, are you expecting sensor failures.?

E

Thanks E

I think i will use a MAX14571. I think this will be enough for what i need.

Thanks again for your replays