A NiCd battery would normally be charged at a constant current, not a fixed voltage. I suggest you visit www.batteryuniversity.com for guidance.
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Sigh
I believe Basics are the problem with this kind of stuff.
If the person you are trying to teach does not know the fundamental rules.....you will never ever get anywhere.
A hard road for any teacher to travel.
Just knowing Ohms Law for example would be a solid start for anyone REALLY interested in Electronics.
I am not getting involved here.
But yes, I had to chirp as usual. Solid Basics are the secret. Ohms Law is ingrained in my Brain. V over R X I. Many people sit and look amazed when my little brain can calculate stuff....and the answer is given to them without the use of a Calculator.
Only the Basics. I can make that Formula talk( if it could) because I know it so well.
Regards,
tvtech
Not all are like you man! I am not a person from electronics field, I had finished university but not with electronics. It is my most interesting hobby. I think you forgot your starting phase.
I don't know what is your intention but it feels so bad if one tried to learn another strange subject but expert laugh or insult at learner. If I am a very wrong person here (because I am very basic at electronics) then dear moderators, why don't you delete my each post???
Hello Willen
I never laugh at people trying to learn Electronics. I still have lot's to learn too. I simply stated the obvious in that Basics are VERY important in order for things to make sense.
Regards,
tvtech
Thank you dear tvtech, that is why each simpler Ohm's law makes me so happy when I find it on real circuit. It's nice to learn here, because here are very experience members like you, MrAl, alec-t, audioguru and other more.... Thank you lot to them!!!! Nice guys!
Thank you dear tvtech, that is why each simpler Ohm's law makes me so happy when I find it on real circuit. It's nice to learn here, because here are very experience members like you, MrAl, alec-t, audioguru and other more.... Thank you lot to them!!!! Nice guys!
LOL I am not a dear and all. And Ohms Law is Ohms Law......no simpler versions available yet as far as I know....
Glad you like the all the long time Members like MrAl,alec-t,audioguru as well. I like them all too
When they speak, I listen very closely. So I can learn too.
My field is CRT TV. Know it well. Other than that , I listen and learn here. Love it .
Best Regards,
tvtech
.......ill be times when the efficiency is quite low meaning a large part of the energy stored in the battery goes to waste. This is the basic nature of the shunt regulator.
Is this design process more clear now?
Hi again Willen,
First, as to the term of endearment, "dear", here in America we usually only say that to the opposite sex so you might get some bad results using it as you would in your country. It does not bother me anymore because i have heard this term used by other peoples in other countries on multiple occasions and i realize it is just a part of the culture. But as i said many people will find this strange here in this country so you may want to think about that. A good substitute here might be "dear friend".
Oh yes! Another problem has been solved! But what is the charging voltage (Vout) here? Is it just a current limiter (instead of voltage reg.)?Here's how a TL431 could be used as a voltage reference for a simple constant-current charger for a NiCd battery....
It's whatever the battery needs across its terminals to maintain the constant current, so Vout is variable. The circuit tries to hold the current constant; it doesn't just limit it to a maximum value.But what is the charging voltage (Vout) here?
LTspice. You can download all sorts of models (including the TL431) free from the Yahoo LTspice User Group.Which simulation programme you used?
It's whatever the battery needs across its terminals to maintain the constant current, so Vout is variable. The circuit tries to hold the current constant; it doesn't just limit it to a maximum value.
LTspice. You can download all sorts of models (including the TL431) free from the Yahoo LTspice User Group.
Can't I use 5V supply even if I decrease the value of emitter resistor to around 5 ohms or less?5V won't be enough for that charger circuit to charge a 3.6V battery.
Not in my circuit. The emitter resistor is what sets the current. The 431 is configured as a 2.5V reference, so the emitter voltage is 2.5 - 0.7 = 1.8V. The collector voltage must be >1.8V, so the battery on charge would have to have a voltage < (5 - 1.8), i.e. < 3.2V.Can't I use 5V supply even if I decrease the value of emitter resistor to around 5 ohms or less?
It won't be simple if it's to be safe, reliable and automatic and you want a long battery life. All of the circuits linked to have limitations.I want to make simpler charging circuit for lead acid battery of around 12V, 10Ah so I need almost 1.5A charging current.
It won't be simple if it's to be safe, reliable and automatic and you want a long battery life. All of the circuits linked to have limitations.
Is your 12V battery a wet-plate type or SLA? What supply voltage will you use? What environmental temperature range will it be charged in? Will the battery be on permanent float charge or just charged periodically? Will it be unattended while charging? Which version of the LM317 do you have?
Well that will have shortened the battery lifeFew days later I tested the charging voltage and it was 24V DC and 4A current hee hee hee
Here's how a TL431 could be used as a voltage reference for a simple constant-current charger for a NiCd battery. There is very little power wastage in the '431; most wastage is in Q1. The values shown would give a charge current ~ 88mA, for supply voltages varying from 9V to 7V over a 15°C to 30°C temperature range. Note the WARNING! The circuit has no way of terminating the charge automatically so would be unsafe left unattended. I don't recommend building it: it's just for educational purposes to show the principle of operation.
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