Is there any problem on pluging/unplugging simple devices to my power source that only require power (no data cable) while the computer is on?
For example :
- Fans.
- LED lights.
- Water pumps intended for computing.
As can be seen, these devices have no data interaction with the computer or motherboard.
I assume that a hard disk must not be plugged/unplugged while the computer is running, but a hard disk has a second connection cable for data. That is not the case for devices like the above referred in the examples.
Is this operation supposed to be safe?
NOTE 1:
This question is not asking about devices like:
- Hard disk drives (IDE, SATA, SCSI… etc).
- DVD/CD internal drives.
- USB devices.
The devices this question refers are only power-requesting ones, not "intelligent" and complex devices capable to maintain an effective communication with the software: they will not be detected by the operating system.
WHY SHOULD YOU NEED THIS FOR?
Basically, just to avoid the need for additional power sources to turn on/off things like:
- Fans cooling the computer case or the external radiators that many people (like me) likes to manage in a manual way (turn it on/off whenever I want).
- LED lights that you want to turn on only some times to check the inner computer (i.e: if you use liquid cooling it is good to check there was no spilling).
- Water pumps: when you have more than one (I have 3 on my main computer) pumping the same circuit, you manage the speed of the water with the simple method of turning them on or off (I always have 1 pump running, and sometimes I turn on the others).
- Peltier plates: they are 12 Volts devices, but they take too much consumption (15 Amps is not unusual), so you sometimes will want to turn it off.
NOTE 2:
We are talking about plugging/unplugging devices to the power supply, not to the motherboard (or Fans to the graphics card… etc).
Best Answer
LEDs and Peltier plates are perfectly safe to hot plug. It will create a very small voltage drop on the 5v or the 12v but any respectable power supply should be able to handle it. Peripherals connected on the same rail will see that voltage drop but they should not be that sensitive to voltage input. Even hard drives can take it.
Fans and Pumps contain an electrical motor. Not only will the voltage drop go lower but it also often causes a power surge when they pull their initial current. It MIGHT be safe to hot plug directly to the power supply but NEVER hot plug a fan/motor directly on a motherboard fan header. The surge will almost certainly cause damage to it!
Unplugging is never an issue unless the device you want to unplug is pulling high current, it could spark and damage the connector. Also remember that a power failure could harm certain devices. Most wont have a problem but hard drives, for example, could be harmed by a power failure.