1

So I have this raspberry pi 3 with a external HDD 500GB and a usb 3.0. The raspberry has only USB 2.0 ports.

So when I plug the HDD in the raspberry the HDD does not show in the file explorer, the bigger problem is that when I plug it it, all my other devices(mouse, keyboard and flash) instantly die and I have to pull out the HDD to proceed using my mouse and keyboard.

The HDD is working perfectly on my laptop(on both my USB 3.0 and USB 2.0 port).

Can I somehow make my HDD work with my raspberry or will I have to get a new one ?!

Improve this question
6
  • The reason it shuts down all your other USB items, is because the raspberry pi can't provide enough power to the hard drive. You need a externally powered USB hub.
    – mt025
    Commented Sep 10, 2016 at 20:22
  • what is that and where would I be able to connect that ?!
    – Harton
    Commented Sep 10, 2016 at 20:24
  • So its a USB hub, you connect it to your USB port on the raspberry pi, plug in into the wall and then plug your hard drive into it. Have a look at this post for more info. superuser.com/a/656097/624775
    – mt025
    Commented Sep 10, 2016 at 20:25
  • define wall, can you send me a link to a usb which would do the job, write an answer
    – Harton
    Commented Sep 10, 2016 at 20:31
  • @Harton - The same plug your computer is plugged into, your lamp, your television. Its called a power plug or a wall plug. Yes; The reason your HDD isn't working is because of the power requirements for the drive. Your PC works because it can supply enough power, although if you had enough of those drives connected to your PC, there is also a limit what your PC supports. This is all documented in the USB specifications. Have you had a chance to look at it?
    – Ramhound
    Commented Sep 10, 2016 at 20:58

2 Answers 2

Reset to default
0

I have this raspberry pi 3

with a external HDD 500GB and a usb 3.0.

A external 500GB USB2 harddisk and a USB3 pendrive?
or a 500GB external USB3 harddrive?

When I plug the HDD in the raspberry ... all my other devices(mouse, keyboard and flash) instantly die and I have to pull out the HDD to proceed using my mouse and keyboard.

This is almost certainly because the HDD is drawing more power than the Pi can supply.

The board has a single MicroUSB power connector and a undefined PSU. (Undefined as, you have to provide this yourself. Often an USB charger is used that depending on the model it those can supply between ½A and 3Amp. You did not mention which PSU you are using.

However, that thing needs to power both the rPi (using up to 1Amp) and all peripherals. A HDD (especially one which spins up) draws a lot of power. It is very likely that you are exceeding your power budget.

Without knowing precisely which PSU is used, which other devices are plugged in and how much your HDD draws it is hard to say though. As a rough figure: 2½ drives tend to draw about 650mWatt.

Citing RPi documentation:

The Raspberry Pi 3 is powered by a +5.1V micro USB supply. Exactly how much
current (mA) the Raspberry Pi requires is dependent on what you connect to
it. We have found that purchasing a 2.5A power supply from a reputable
retailer will provide you with ample power to run your Raspberry Pi.

Typically, the model B uses between 700-1000mA depending on what 
peripherals are connected; The maximum power the Raspberry Pi can use
is 1 Amp. If you need to connect a USB device that will take the power
requirements above 1 Amp, then you must connect it to an externally-
powered USB hub.

The power requirements of the Raspberry Pi increase as you make use of 
the various interfaces on the Raspberry Pi. The GPIO pins can draw 50mA
safely, distributed across all the pins; an individual GPIO pin can only
safely draw 16mA. The HDMI port uses 50mA, the camera module requires
250mA, and keyboards and mice can take as little as 100mA or over 1000mA!
Check the power rating of the devices you plan to connect to the Pi and
purchase a power supply accordingly.

Can I somehow make my HDD work with my raspberry or will I have to get a new one ?

The normal solution for this would be to either plug a PSU into your external drive (many ship with an option for external power but without matching PSU, hoping that they can draw enough power out of an USB interface), or an powered USB hub. In this case that hup will have its own PSU and can supply up to 500mA (USB2) or 900mA (USB3) to the harddrive.

Improve this answer
1
  • Arg. beginners mistake. One whioch I made quite a few times (and corrected most of the time before comitting)..
    – Hennes
    Commented Sep 12, 2016 at 15:56
0

You might try to solder a wire from the input +5V DC power micro-B connector [power jack] to proper VBUS pin on USB connector on your Pi-3 board.

ADDENDUM1: Older Raspberry Pi boards did have a resettable polyfuse MINISMDC014 in power line to VBUS. These fuses have the nominal current at 140mA, and trip point at 280mA, which does not even meet the basic USB specifications (500mA). It is obvious that a 800-900mA typical power to USB3.0 enclosures are too much for this. Dropping a wire from mini-B DC input to VBUS at USB connector will bypass the fuses. Unfortunately, full schematics for Pi-3 is not available to me (even when I do have the development kit), so I can't provide more details.

ADDENDUM2: It appears that Raspberry Pi project has a long history with weak power over USB ports, coming back 5 years, it appears to be a well known issue. Some people have arrived with "wire bypass" solution independently and somewhat ahead of me :-). The Pi officials claim that all Pi's, from Zero to 3, are USB-compliant. It might be even true. However, what they forgot to mention in any Pi documentation is that they apparently have designated the device as "low-power embedded host", which means that they do not have to supply more than 100mA per port, and the voltage can drop down to 4.4V. Yet the retail kits do not mention this, they simply state "Four USB 2.0 ports", setting up default expectations from users.

Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .