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Porter22
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I have a 2 AMP regulated DC power supply, with variable voltage 3 - 12 v. If in a small circuit, i.e, small copper wire with 1 ohm resistor. Why am i not getting at max Amps?
Porter22 said:I have a 2 AMP regulated DC power supply, with variable voltage 3 - 12 v. If in a small circuit, i.e, small copper wire with 1 ohm resistor. Why am i not getting at max Amps?
]magoo said:What does your power supply look like? Doesn't it have its own resistance? Have you considered that?
Also what kind of batteries could I use (in short bursts to avoid battery malfunction) to measure high A in discharge?davenn said:does your power supply have current limiting? if so, then that is what is happening when you are presenting the PSU with a short circuit
as magoo asked ... what sort of PSU ?
Dave
Not with that power supply. It's output is rated at 2A max. Try putting 12V across a 6 Ohm power resistor. How much power will that be? (Be sure to use high enough wattage resistor to not smoke the resistor).Porter22 said:the wire has .3ohms. So at 3V, shouldn't i be getting 10 A?
Based on your questions, there are no batteries that you should try to use to obtain high output currents. You don't have the experience yet to be working with high powers. That's how batteries fail and burst or catch fire...Porter22 said:Also what kind of batteries could I use (in short bursts to avoid battery malfunction) to measure high A in discharge?
Porter22 said:I attached a pic of the PSU..
I have done some calculations assuming (generously and for simplicity, i think) that the wire has .3ohms. So at 3V, shouldn't i be getting 10 A?
I understand there may be "short-circuit" prevention elements in this PSU. Is this what you're talking about?
berkeman said:Not with that power supply. It's output is rated at 2A max. Try putting 12V across a 6 Ohm power resistor. How much power will that be? (Be sure to use high enough wattage resistor to not smoke the resistor).
Based on your questions, there are no batteries that you should try to use to obtain high output currents. You don't have the experience yet to be working with high powers. That's how batteries fail and burst or catch fire...
http://techbakbak.com/wp-content/uploads/2016/01/hoverboards-are-setting-homes-on-fire.jpg
View attachment 118370
In the series current measurement mode, a DMM has a non-trivial resistance. That is how it makes a small voltage to figure out what the series current is.Porter22 said:I got variable 25 W resistor, and set it to 6.0 ohms. Which should give 2 A of current and 24 W power through the resistor. I'm currently reading 0.28 A at 12 V... Whats going on here?
If I measure the resistance of the entire circuit I'm getting 0.685k Ohms which would give .0175 Amp. which also doesn't really make sense... Everything is in series, including multi meter. Have also tested with analog Voltmeters and Ammeters DC. Is the power supply really that that current limiting that i can't even get close?
berkeman said:In the series current measurement mode, a DMM has a non-trivial resistance. That is how it makes a small voltage to figure out what the series current is.
Take the series DVM out of the circuit and just measure the resistance of your potentiometer before hooking it in. Then just monitor the voltage across that resistance to figure out the current. That's a much less invasive way to figure out the current.
And is your potentiometer capable of handling 25W? Probably not, so just be ready to disconnect it quickly if it overheats...
The maximum safe DC amperage for a 14 AWG copper wire is typically around 15 amps.
No, 14 AWG copper wire is not suitable for high voltage applications. It is designed for low voltage and low amperage circuits.
The amperage rating for a circuit using 14 AWG copper wire can be determined by consulting the wire's ampacity chart. This chart takes into account factors such as wire length, ambient temperature, and insulation type.
Yes, 14 AWG copper wire is suitable for outdoor use as long as it is properly rated for the specific outdoor environment and conditions.
It is generally not recommended to use a thicker gauge wire for a circuit that is designed for 14 AWG copper wire. This can cause issues with the circuit's resistance and potentially cause damage or overheating. It is best to consult with a professional or refer to the ampacity chart for guidance on selecting the appropriate wire gauge for your circuit.