Sparky DC.. normal?

[ksrimoungchanh]

Hello All:

I am a customer in the US that uses 110v. Since I received my package from SD, my unit has always sparked when I plug power into the unit. Not only that, but I have not completed a disk image any faster then 6 days.. even with new hard drives for testing. I have purchase new drives just for testing and with only 10G of data, it takes over 4 days to image.

SD says they tested it on 220v and it works fine? They are also saying that they have many US/Americas customer that are not having any issues?

Anyway, has anyone have had same symptoms? Any US base customers here? I am interested in a true customer response, not a "reseller" or "partner" response.

thanks in advance,

Kou

[craig6928]

i would check that your power socket is ok in your home.

if the unit is sparking that down to your plug socket in the wall.
possible the plug is breaking down.
or infact the lead that connects to the data compass.

have you tried it on a anti surge power socket.
do you get the same effect.



disk imager should not take 6 days

of topic now

i got a atola imager and it can clone a 320gb hard drive in less then two hours.


i read on salvation data forum that someone else was complaining about the imaging of the drives
and they said that they fixed this
with a new firmware update



110v should work fine no sparks at all unless the socket is bad

[craig6928]

how your getting on with this m8

[ppumkin]

Hi

Regarding the sparking of the dc jack

I just bought the DataCompass and the same thing happens. When you plug it in sparks came out as if it was shorting out
Im in the UK 220volt.

The unit uses normal laptop 19v centre pin + power unit. It seemed strange to me too and only saw this type of effect on reverse polarity appliances.

It could be possible that the wiring inside the DC is reversed. It wont damage your hardware and it seems that USB negative and Mains negative is isolated so it should not cause damage to your PC.

Do not plug in near anything flammable though.. (eg. Methylated spirits..)not that you should have any just lying around..

If in fact your DataCompass does not work. Salvation will replace it for you.

Oh- the image story is most likely not realted to the sparking-
Depending on how you set up the imagain - using UDMA, pre-fetch, RAW or shadowdisking will dramitically increase decrease time + any bad sectors? faulty hdd also depends on this.. Be sure to use High density Cable from DC Unit if usin UDMA and always use low density cables for HD Doctor ( edit- saying that i use high density with no problems on all devices... )

Cheers

[fzabkar]

Regarding the sparking of the dc jack

I just bought the DataCompass and the same thing happens. When you plug it in sparks came out as if it was shorting out
Im in the UK 220volt.

The unit uses normal laptop 19v centre pin + power unit. It seemed strange to me too and only saw this type of effect on reverse polarity appliances.

It could be possible that the wiring inside the DC is reversed. It wont damage your hardware and it seems that USB negative and Mains negative is isolated so it should not cause damage to your PC.

The polarity is not an issue. And there is no such concept as mains "negative".

What is most likely happening is that there is a high impedance ceramic capacitor between the negative terminal of the 400V electrolytic bulk capacitor on the primary side, and the negative output terminal on the DC side. I suggest you use your multimeter to measure the potential difference between mains earth and circuit ground.

[Alwin]

I also have a 'sparky' DC device.
I guess it has to charge up some capacitors or something.

[poehere]

Only way I find it does not spark is this one. Take the end of your power adaptor and separate them. Plug half into electricity and half into drive set it all up then attach them together and then add on usb. Otherwise it sparks all the time on this one. Only good on small drives so not a lot of use on this tool now considering drives are more then 500gb

[craig6928]

that is what you call bad design if the capacitors are not discharging when you turn of the unit.
where it should have a circuit to discharge the power supply

poor quality control in there department

[guru]

More "Made In China" cr*p

[craig6928]

remember most electronic items are made in china

[thatdellguy]

"China Quality"

[fzabkar]

Only way I find it does not spark is this one. Take the end of your power adaptor and separate them. Plug half into electricity and half into drive set it all up then attach them together and then add on usb. Otherwise it sparks all the time on this one. Only good on small drives so not a lot of use on this tool now considering drives are more then 500gb

That is what is technically referred to as a "bodge".

The "problem" is that there is a potential difference between mains earth and device ground. The spark occurs when the potentials are equalised.

To avoid the sparking, you could replace the power supply's 2-pin (?) mains cord with a 3-pin type, and then run an earth conductor between the earth pin and the negative terminal on the secondary side of the supply. I doubt that this will introduce any earth loops.

As for "Chinese" quality, the same arrangement is used in all manner of 2-pin appliances that are built with switchmode PSUs. You will invariably find a small, high impedance capacitor linking the primary and secondary sides of the supply.

For example, see the capacitor straddling the hot/cold demarcation line, to the right of the optocoupler:
http://www.users.on.net/~fzabkar/DVD/TD ... os/PSU.jpg

Or see the caps and resistor at the bottom of this LG TV circuit:
http://www.users.on.net/~fzabkar/MB-042C/PSU-LR.jpg