0
\$\begingroup\$

How does compare using one power supply for multiple devices vs each device having its own - regarding efficiency eg. power consumption?

Model situation: Home automation using low power devices such as sensors with Arduino, Raspberry Pi, Esp8266. Given 5-12V is not smart over long distances in a house, assume 24V power supply.

Choice:

  • Put low voltage cabling and power devices either directly from 24V or use a voltage converter to step-down to 3, 5, 12V respectively.
  • Each device will have its own small power supply from mains voltage, such as hi-link or similar.

Is there another aspects to consider aside from obvious like labour and cost of putting separate cabling?

\$\endgroup\$
1
\$\begingroup\$

Distributing 5 V or 12 V can be smart if the currents are low enough (much less than 100 mA for example) so voltage drop isn't an issue. But an RPi already exceeds that.

Other things to consider:

Reliability, if everything is running on that 24 V and it breaks, nothing works. If you use a mains adapter for each device, the risk is more spread out. Also you might have a spare adapter available or swap an adapter until you have replaced the faulty one.

Efficiency, the 24 Adapter will need to power everything at full load. That might mean it is much less efficient at lower loads. Compare with PC power supplies, these can deliver a lot of power but often only reach their rated efficiency when loaded with at least 60 % of their maximum load.

In my opinion, unless you have many low-power devices, using a 24 V distributed power is not worth the trouble.

\$\endgroup\$
0
\$\begingroup\$

Extendability: all devices you can buy come with a mains power supply.

Now, you buy a new Smart HamsterTM and it comes with a special wireless charger that has mains on one side, and a special place for your Smart HamsterTM to go to recharge. Your 24 V system is useless, because you don't want to (also, can't) redesign that system to use 24 V.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.