24V (upto 4A) battery charger design with auto cutt off

[shahbaz.ele]

dear all
I need to design a 24V battery charger.
Amperes could be 4A max.
could I design it using LM317K or some other thing?

 

[Picbuster]

dear all
I need to design a 24V battery charger.
Amperes could be 4A max.
could I design it using LM317K or some other thing?

Do not use analogue regulators at 4 amps 24V.
A voltage drop let’s say 30-24=6V create a heater from 4 x 6 = 24 Watt.
Use a switched supply easy to create from a small Pic, coil, powerfet and one opamp to regulate the current. A 16Fxxx with analogue inputs will do.
Measure voltage, measure current and regulate the PWM to the gate of the power fet.

 

[shahbaz.ele]

dear can you give block diagram of this scheme.
or some circuit designed of this type

 

[Picbuster]

dear all
I need to design a 24V battery charger.
Amperes could be 4A max.
could I design it using LM317K or some other thing?

A simple block attached you only have to calculate values.
This is simple and at a low level mathematical/electronica level.
good luck

 

[shahbaz.ele]

dear you may forgot to attach figure.

 

[Picbuster]

dear you may forgot to attach figure.

You should have it now.

- - - Updated - - -

dear you may forgot to attach figure.

http://obrazki.elektroda.pl/3025170100_1375687546.jpg

 

[shahbaz.ele]

dear picbuster
.jpg image still not opening.

 

[tpetar]

dear all
I need to design a 24V battery charger.
Amperes could be 4A max.
could I design it using LM317K or some other thing?

You can to use LM338K TO-3, its 5A linear voltage regulator. This regulator is very reliable. Of course if you look to make power efficient device you can try with switching voltage regulator.


For two lead acid batteries with nominal 12V voltage, float charging voltage is 27,6V and cycling voltage is 28,8V.

Lets say that you need at least 3V Vi-Vo difference, Vi (float voltage) should be 30,6V and Vi (cycling voltage) should be 31,8V.

Power dissipation for LM338K in 3V difference and at 5A is 15W, which this regulator handle without problem, efficiency is other story.

For LM338K TO-3 maximum input voltage is up to 35V and maximum dissipation power is up to 50W.
For LM338T TO-220 maximum input voltage is up to 35V and maximum dissipation power is up to 25W.


I use LM338K regulator a lots for battery chargers, I can say its very reliable and almost undestructable if you make all properly.



Best regards,
Peter

 

[pradeep.g.belchada]

but what is the input voltage of battery charger does it powered from mains 230v or any other volt

24V (upto 4A) battery charger design with auto cutt off

dear all
I need to design a 24V battery charger.
Amperes could be 4A max.
could I design it using LM317K or some other thing?

 

[shahbaz.ele]

Input is from mains 220VAC.

 

[tpetar]

Input is from mains 220VAC.

This doesnt change situation, you should use transformer or SMPS design to lower voltage, rest is the same.


Best regards,
Peter