need help to build circuit tester

[ianhem]

Hello I have a small project, I'm not an overly good either.

I want to build a simple test lamp that uses an LED to indicate that a circuit at 24v can supply 5 amps.

I could use a bulb but would prefer to use an LED.

Any help would be appreciated

Thanks

Ian

 

[ericgibbs]

hi Ian,
Do you want the LED to indicate 24V or that a 5Amp current is flowing in a circuit.?
E

 

[audioguru]

I want to build a simple test lamp that uses an LED to indicate that a circuit at 24v can supply 5 amps.
I could use a bulb but would prefer to use an LED.

You need a circuit to detect that the 24V has not dropped when it is loaded with a HUGE 4.8 ohms/120W resistor.
Maybe you could use two 12V/60W car headlights in series as the load.

 

[dougy83]

in addition to the load that AG mentioned, the circuit to detect the 24V can be simply a TL431 with resistor divider to provide 2.5V at the reference terminal when 24V is supplied to the circuit. An LED and resistor can then be connected between the cathode and 24V supply.

 

[ianhem]

Thanks for your replies.
Eric
I would ideally like the LED to show that there is 24v present and it can supply 5 amps.

In response to Dougy How do I do that?

Ian

 

[dougy83]

Circuit attached. You can use a 10k variable resistor in place of the 8k6 resistor if you want. The load is at AG described above.

 

[alec_t]

I hope you won't be testing 24V circuits that aren't intended to provide as much as 5A. The 4.8 Ohm load could well result in release of the magic smoke .

 

[ianhem]

Thanks Dougy