Is making this kind of circuit with flip flops and gates will be simpler?

 

I did some changes, now the current is very low,
what am I doing wrong?
View attachment 120998

To measure current, the current must flow through the meter. It must be measured in SERIES. With the load.

Alternatively, you can measure the voltage drop across the 1.25 ohm resistor and calculate the current with ohms law.

 

Also, why are you not fixing the connection to the LEDs op amp? For simulation, remove the 3300uF cap.

 

 

Measure voltage across R2 and report.

Then press reset switch and report results.

 

Measure voltage across R2 and report.

Then press reset switch and report results.

before i press its 11.336 volt
and after i press its 5.86 volt

 

before i press its 11.336 volt
and after i press its 5.86 volt

And does that change the current flow at motor? (actually, voltage drop across 1.25 ohm resistor?

 

Hi, i need to build a circuit with the following spec:

using a 12v supply I need to run a 6v servo motor (with internal resistance of 10ohms)
-when the current on the motor will be more than 1A, i need to cutoff the power to it, and light a red led light.
-when the current goes down 1A, the power can only be restored by pressing a reset switch (which will also will turn the led light off).

the thing is i can only use simple components (diodes, transistors, resistors, op amps etc, NO IC, relays, software...)

Thanks



Moderator's Note.
Please don't do double post, one thread is enough.

No programmed chips? Okay what is allowed? Op amps, voltage comparators and logic?
Attached is a consideration for a design, not exactly to fit your needs, but would this design be okay?

 

Hi, i need to build a circuit with the following spec:

using a 12v supply I need to run a 6v servo motor (with internal resistance of 10ohms)
-when the current on the motor will be more than 1A, i need to cutoff the power to it, and light a red led light.
-when the current goes down 1A, the power can only be restored by pressing a reset switch (which will also will turn the led light off).

the thing is i can only use simple components (diodes, transistors, resistors, op amps etc, NO IC, relays, software...)

Thanks



Moderator's Note.
Please don't do double post, one thread is enough.

Okay, only an op amp and parts. Not a complete design yet. It is a 6 V regulator, current limiting set to 1 A. Reset button. LED on over current. Allowing for over current on power on to the motor. Another starting point.
Still some designing required.

 

Okay, only an op amp and parts. Not a complete design yet. It is a 6 V regulator, current limiting set to 1 A. Reset button. LED on over current. Allowing for over current on power on to the motor. Another starting point.
Still some designing required.

the circuit looks good, and thank you for the extra information.
i really liked the voltage divider you added (exactly what i needed)
but the thing is on the simulation - when i get more current on the motor - there a big voltage drop.

I'm using multisim, i couldnt find LM334 - so i used LM333K instead - is that okay?

 

this is m design, any suggestions?