Voltage Drop

Hi, I am trying to resolve an issue of voltage drop across a circuit. I have designed a home automation system utilising the Arduino ESP32. The Arduino controls a series of end of line devices rated to 5v 1.5A. Currently the Arduino is powered via a 5v 5A transformer, however as the end of line devices are 10m away, when I activate them the voltage drops depending on the overall load. Approximate voltage drop 1-2v.

I have tried powering the Arduino via a 9v supply, installing a Liner Voltage Regulator on the end of line devices effectively supplying a constant 5v supply. This now introduces a heat problem where I have to install a heatsink on the regulator to dissipate the heat.

My question is “Is the Liner Voltage Regulator the best way to regulate the voltage?”

If not what should I be doing to resolve the issue?

you need a primary supply 9 volt 5-7 amp supply depending on your needs and have a look here you will need two of them…or units similar to these

i would not bother to use the linear supply regulator…

you need two of them that is…one for your aurdino adjust this for 5 volts

if your voltage drop is 2 volts below at the end of your cable run then you need to adjust the regulator according to the required voltage at your devices…etc …etc.

so the output of the regulator may need to be around 7 volts…on one regulator.that powers your devices… and power the aurdino of the second regulator adjust for 5 volts .

I wouldn’t recomend increasing the input voltage to compensate for the line voltage drop for a device like the esp32. When you current drops the voltage at the device will go up and could go higher than the maximum voltage for the device.

You have two options:

  1. Decrease the resistance ib the wiring to reduce the voltage drop. You can do this by running thicker cable or multiple cables in parallel.
  2. Run a higher voltage which reduces the current and also the voltage drop and regulate the voltage at the device. As you noted, a linear regulator gets hot because they are very inefficient. As recomended by @brian86770 a DC-DC buck converter is very efficient so wont develop anywhere near as much heat.

My question is “Is the Liner Voltage Regulator the best way to regulate the voltage?” NO
Liner Voltage Regulators are excellent devices, but they have to dissipate the difference in voltage between input and output times the current.
eg 12V in, 5V out, 1.5A current. Power dissipation (12 - 5)*1.5 = 10.5 Watts.

Because your devices are rated at 5V 1.5A, you should use a separate supply for them and a separate supply for the Arduino; with the GNDs connected, so the logic works. That way the Arduino receives a steady 5V and the device voltage can vary. What are the devices ??

You say “the Arduino is powered via a 5v 5A transformer”
Is that 5V DC ??
Is the Arduino a UNO or similar ??
Are you using the 5V pin on the UNO to power the devices ?? because it is not designed to do that.

If you can provide more information I am sure a solution could be found.

(Core Electronics Customer)