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Need a current limiter/step down design.

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northendtrooper

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I have way too much current going back to my DC power supply (6v/6a). I have a 4 ohm heating element that I need to keep up at max current. What could be used, minimally in parts, to bring down the amps to keep from killing/cooking my DC supply.
Cheers,
trooper
 

I have way too much current going back to my DC power supply (6v/6a). I have a 4 ohm heating element that I need to keep up at max current. What could be used, minimally in parts, to bring down the amps to keep from killing/cooking my DC supply.
Cheers,
trooper


Usually fuse is used to protect circuit from overcurrent.

In your case if you use 4R load this is 6V/4R=1,5A (1,5A of current).

1,5A is safe for your psu.

That heating element change resistance during heating ?

Additional power resistor can be added in serie with load to decrease current if needed.


Best regards,
Peter
 

Usually fuse is used to protect circuit from overcurrent.

In your case if you use 4R load this is 6V/4R=1,5A (1,5A of current).

1,5A is safe for your psu.

That heating element change resistance during heating ?

Additional power resistor can be added in serie with load to decrease current if needed.


Best regards,
Peter

The dimensions that I am using can't allow a fuse. The heating element is an inch of Nichrome so the changing of resistance is minimal. I am using AA batteries in series so if 1,5 is safe for the return without them melting then sweet! I haven't heard of a 4R load, could you teach me! Would that 4R keep from my Nichrome reaching maximum temperature?
 

The dimensions that I am using can't allow a fuse. The heating element is an inch of Nichrome so the changing of resistance is minimal. I am using AA batteries in series so if 1,5 is safe for the return without them melting then sweet! I haven't heard of a 4R load, could you teach me! Would that 4R keep from my Nichrome reaching maximum temperature?

There is small fuses in SMD cases.

I dont know can you get 1,5A for AA batteries, its sound very optimistic for that batteries. I supose that batteries are called "Die Hard". If you use them in serie you just increase voltage not current.


R is Ω

4R means 4Ω

If you want to decrese current more add additional resistor in circuit as I mention earlier.


Best regards,
Peter
 

There is small fuses in SMD cases.

I dont know can you get 1,5A for AA batteries, its sound very optimistic for that batteries. I supose that batteries are called "Die Hard". If you use them in serie you just increase voltage not current.


R is Ω

4R means 4Ω

If you want to decrese current more add additional resistor in circuit as I mention earlier.


Best regards,
Peter
Peter,
I just got back from doing some quick measurements. Excuse me that the resistance that I am looking at for my nichrome coil is .1-.4 ohms, yes it is very small. I have a stack of AA Duracell Copper Top batteries in series putting down 6v and 9amps. Each Copper top has the ability of 2+amps.
I need a circuit that will allow the nichrome to heat up to 800 degree (I did the math for this gauge and amps) and have a following circuit/chip to down the volts/amps back to the battery so it doesn't heat them up. Basically too much current/voltage back to the batteries. I am researching transformers, inverting amp, capacitors and inductors for my solution. I can't do much resistance because the low impedance of the nichrome.
I see what you mean by 4R, it has been a long time since I have talked electronic tech lingo so please bare with me.
 
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