Cory Papenfuss wrote:
On Wed, 26 Oct 2005, keith_w wrote:
Gonz wrote:
In another group, I read about the Lenmar ACON6, which supplies 2.1A
@ 6.5v. The voltage is correct, the current is just shy of the 3A
that the Pentax supplies, but it seems to be just overengineered. I
have used it extensively for portraits and sensor cleaning and it
works like a trooper. It was real inexpensive too.
rg
2.1 Amps vs. 3.0 Amps is only 70% of the current rating the maker
believes the power supply should present to the load.
I don't call that "...just shy of."
Not when you're dealng with power supplies!
I didn't go so far as to put high-frequency datalogging on my
measurments of the *ist-DS current, but what I did see was WAY below 3A.
Even the spike when the flash fired and started charging again was about
1.5A. The limits on these classes of power supplies are usually
thermal, not absolute current.
Great find on that power supply... looks like a reasonable price for
a good (switching) unit.
-Cory
Fair enough.
I do know that with marginally rated supplies, when they get or are
asked to operate near their rated limits much, they don't seem to take
well to surges and such.
If you've got an under-rated supply, sort of with a "safety factor" in
power rating built in, you'd probably be okay with a smaller supply.
On the other hand, sometimes you find people, like you, that know what
they're doing and understand measuring and subsequent understanding of
what the NEED is. In which case, have at it!
keith
