On 4 October 2013 20:28, Jan Kandziora j...@gmx.de wrote:
[snip]
In addition,
measuring low temperatures with parasite power is bad, as it heats the
sensor and thus, gives you slightly wrong temperature values.
I don't understand why this is worse when measuring low temperatures
than high.
Without comment on the details of this situation, that is not how
convection and conduction work.
Convection is typically described by Newton's law of cooling: q=hA(T-Tamb)
Conductions is q=k*dT/dx ~k (Tsurf-Tamb)/dx
Thus the heat transfer rate depends explicitly on the difference between
On 5 October 2013 09:31, Colin Reese colin.re...@gmail.com wrote:
Without comment on the details of this situation, that is not how
convection and conduction work.
Convection is typically described by Newton's law of cooling: q=hA(T-Tamb)
Conductions is q=k*dT/dx ~k (Tsurf-Tamb)/dx
Thus the
I'm not sure I caught all of that, but at steady-state:
Pdissipated = qconduction + qconvection
= k (Tdevice - Tamb)/ (thickness of boundary layer) +
hA(Tdevice - Tamb)
If you are dissipating some amount of power, the device will heat to a
temperature above ambient so that the
I agree with what has been said, but a further question - the discussion
refers specifically to parasitic power, does the same not apply to
powered networks? I had always assumed that it did, just that powered
was faster, I am wrong here?
On 05/10/13 09:31, Colin Reese wrote:
Without
Dont forget Planck's law
H
H
Skickat från min Samsung MobilColin Reese colin.re...@gmail.com skrev:I'm not
sure I caught all of that, but at steady-state:
Pdissipated = qconduction + qconvection
= k (Tdevice - Tamb)/ (thickness of boundary layer) +
hA(Tdevice - Tamb)
If you
Am 05.10.2013 11:01, schrieb Mick Sulley:
I agree with what has been said, but a further question - the discussion
refers specifically to parasitic power, does the same not apply to
powered networks? I had always assumed that it did, just that powered
was faster, I am wrong here?
It's
I assume you are referring to radiation. At this temperature that is not an
issue. You need to get pretty darn hot for it to contribute.
Colin
On Oct 5, 2013, at 11:31, Håkan Elmqvist hak...@smeden.org wrote:
Dont forget Planck's law
H
H
Skickat från min Samsung Mobil
Colin
