Thoughts on using a USB disk on a cheapo UPS?

  • Thread starter Thread starter Al Dykes
  • Start date Start date
A

Al Dykes

I don't have a high opinion of an external USB disk powered by a
wall-wart as industrial-strength kit. Having the PC powered on a UPS
and the Wall wart on house power has potential problems, IMO.

What are the thoughts of putting retail external USB disks on
entry-level UPS systems? These systems are stepped-sine power and
they don't specify switch-over time.

??
 
Al said:
I don't have a high opinion of an external USB disk powered by a
wall-wart as industrial-strength kit. Having the PC powered on a UPS
and the Wall wart on house power has potential problems, IMO.

What are the thoughts of putting retail external USB disks on
entry-level UPS systems? These systems are stepped-sine power and
they don't specify switch-over time.
Click to expand...

I've always found UPS's have a life of less than 3 years.

Yousuf Khan
 
Al Dykes said:
I don't have a high opinion of an external USB disk powered by a
wall-wart as industrial-strength kit. Having the PC powered on a UPS
and the Wall wart on house power has potential problems, IMO.
Click to expand...

The wall-type PSUs are electrically insulated, there should not
be a problem, except perhaps aestetically.
What are the thoughts of putting retail external USB disks on
entry-level UPS systems? These systems are stepped-sine power and
they don't specify switch-over time.
Click to expand...

To what end? It should work, but it only makes sense if you
have the PC on an UPS as well. Also take care to use the
VA rating (V * A as stated on the plug), as switching power
plugs may not have power factor correction.

Personally I have my external USB disks on the PCs
12V power rail, but that takes decoupling (I use
a pair of STPS 3045 for that) and dampening (0.2R or
so, but a 4A fast-acting fuse also dampens enough
for two disks).

Arno
 
The wall-type PSUs are electrically insulated, there should not
be a problem, except perhaps aestetically.
Click to expand...

They are also made by the lowest bidder. Of course, plugging one into
a UPS doesn't change that.
To what end? It should work, but it only makes sense if you
have the PC on an UPS as well. Also take care to use the
VA rating (V * A as stated on the plug), as switching power
plugs may not have power factor correction.
Click to expand...


Voltage differentials, ground loops?
 
Al said:
I don't have a high opinion of an external USB disk powered by a
wall-wart as industrial-strength kit. Having the PC powered on a UPS
and the Wall wart on house power has potential problems, IMO.
Click to expand...
What are the thoughts of putting retail external USB disks on
entry-level UPS systems? These systems are stepped-sine power
Click to expand...

Thats irrelevant. They all rectify the mains, none use the mains directly.
and they don't specify switch-over time.
Click to expand...

I prefer always on/continuous UPSs myself.

They dont necessarily cost anymore now.
 
They are also made by the lowest bidder. Of course, plugging one into
a UPS doesn't change that.
Click to expand...

Yes. But the insulation requirement ensures that you do not get
ground loops or current over ground.
Voltage differentials, ground loops?
Click to expand...

No ground loops with the standard wall plugs. Voltage differential
is not a problem with wide-input ones. With heavy transformer types
it should not be an issue either, but they are less resilient.

Arno
 
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