Using a Resistor to Power Multiple Devices: A Simple Guide

In summary, the conversation discusses the use of a power brick that supplies 12V and 17.9A to a device and another device that requires 12V and 10.83A. The possibility of using a 1.7 ohm resistor in parallel to draw some of the current is mentioned. It is clarified that the 17.9A on the transformer is the maximum current that can be drawn and it is not recommended to push the power supply to its maximum. It is also mentioned that the power supply is external and outputs DC. It is concluded that the 12V and 10.83A device can be powered off the 12V and 17.9A supply without the need for a resistor
  • #1
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I have a power brick (transformer) that sends 12V, 17.9A to a device. I have another device that requires 12V, 10.83A. If I put a 1.7 ohm resistor in parallel to draw some of the current:

[itex]\frac{12V}{17.90A-10.83A}=1.697312[/itex]

Could I use it to power the 10.83A device? I'm just not sure if it is as simple as that.

Also, when it says 17.9A on the transformer, does that just mean that is the MAX current that can be drawn, or is that what it is always sending?

Edit: Sorry I should add that it is an external power supply, so it is outputting DC not AC.

Thanks
 
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  • #2
Jd0g33 said:
I have a power brick (transformer) that sends 12V, 17.9A to a device. I have another device that requires 12V, 10.83A. If I put a 1.7 ohm resistor in parallel to draw some of the current:

12V17.90A−10.83A =1.697312 \frac{12V}{17.90A-10.83A}=1.697312

Could I use it to power the 10.83A device? I'm just not sure if it is as simple as that.

no you don't need all that

Just power the 12V 10.83 A device off the 12V 17.9A supply ... the lower current device will only draw what it needs from the 12V supply
Jd0g33 said:
Also, when it says 17.9A on the transformer, does that just mean that is the MAX current that can be drawn, or is that what it is always sending?

That's the max it can supply, and preferably you never want to push a PSU to its max
Jd0g33 said:
Edit: Sorry I should add that it is an external power supply, so it is outputting DC not AC.

yup I guessed that, tho my earlier answer wouldn't have made any differencecheers
Dave
 
  • #3
Oh Ok. Thanks a bunch Dave!
 

1. What is a simple power supply?

A simple power supply is a device that converts electrical energy from a power source, such as a wall outlet, into the appropriate voltage and current needed to power electronic devices.

2. How does a simple power supply work?

A simple power supply typically consists of a transformer, rectifier, and regulator. The transformer steps down the high voltage from the power source to a lower voltage. The rectifier then converts the alternating current (AC) to direct current (DC). Finally, the regulator ensures that the output voltage is stable and within the desired range.

3. What are the main components of a simple power supply?

The main components of a simple power supply include a transformer, rectifier, and regulator. Other components may also be included, such as capacitors, inductors, and resistors, depending on the specific design.

4. What is the purpose of a simple power supply?

The purpose of a simple power supply is to provide a steady and reliable source of power for electronic devices. It ensures that the voltage and current supplied to the device are within the appropriate range, preventing damage to the device.

5. Can a simple power supply be used for any electronic device?

No, a simple power supply is designed for specific voltage and current requirements. It is important to check the specifications of the electronic device to ensure that the power supply can provide the necessary output. Using the wrong power supply can damage the device.

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