Removing Electric Instruments in Winter .

Is it true or just an "old wives tale " ?

For several years now I've removed all the instruments with liquid
crystal displays ( LCD's) from my sailplane on the advice I got from an
"expert " some years ago . I was told that if you store the glider with
instruments in an outside hangar where the temperature drops to below
-20F at times , then that is very hard on the LCD's . I did in fact
have an old Garmin start up in the Spring one year after winter
storage, the screen turned brown then expired .

Thanks ,

Ron Clarke.

wrote:
Is it true or just an "old wives tale " ?

For several years now I've removed all the instruments with liquid
crystal displays ( LCD's) from my sailplane on the advice I got from an
"expert " some years ago . I was told that if you store the glider with
instruments in an outside hangar where the temperature drops to below
-20F at times , then that is very hard on the LCD's . I did in fact
have an old Garmin start up in the Spring one year after winter
storage, the screen turned brown then expired .

The specifications on modern LCDs vary, but typically the low end of the
storage temperature range is usually somewhere in the range -40C
(-40F) to -20C (-4F). High end is generally 80C (176F).

Marc

In our business, we use a wide variety of scientific and engineering
instruments and sometimes end up in extremes of temperature. We have
had equipment fail to operate at temperatures below freezing, but
recover when warmed up.

LCDs seem to survive in all conditions we have experienced (-20 to +140
F), although they may not all be readable. It's common for
consumer-grade LCDs (such as you might have on a PDA) to suffer from
black screens on hot days here in Arizona. I also found an expensive
oscilloscope with color LCD screen unreadable below freezing, while an
older ( and cheaper) greyscale LCD was fine.

Some solders also may have problems at very low temperatures - if my
memory serves me right, lead has a phase change that can exacerbate dry
joints in sub-zero temperatures. Connectors are also a possible source
of problems, especially if exposed to vibration and temperature
extremes.

Mike


On Nov 28, 5:18 pm, Marc Ramsey wrote:
wrote:
Is it true or just an "old wives tale " ?

For several years now I've removed all the instruments with liquid
crystal displays ( LCD's) from my sailplane on the advice I got from an
"expert " some years ago . I was told that if you store the glider with
instruments in an outside hangar where the temperature drops to below
-20F at times , then that is very hard on the LCD's . I did in fact
have an old Garmin start up in the Spring one year after winter
storage, the screen turned brown then expired .The specifications on modern LCDs vary, but typically the low end of the
storage temperature range is usually somewhere in the range -40C
(-40F) to -20C (-4F). High end is generally 80C (176F).

Marc

It occurs to me that the individual manufacturers might
have the best comment about this. If there is nothing
in the manual, asking a dealer might be the next best
inquiry.

At 15:54 29 November 2006, Mike The Strike wrote:
In our business, we use a wide variety of scientific
and engineering
instruments and sometimes end up in extremes of temperature.
We have
had equipment fail to operate at temperatures below
freezing, but
recover when warmed up.

LCDs seem to survive in all conditions we have experienced
(-20 to +140
F), although they may not all be readable. It's common
for
consumer-grade LCDs (such as you might have on a PDA)
to suffer from
black screens on hot days here in Arizona. I also
found an expensive
oscilloscope with color LCD screen unreadable below
freezing, while an
older ( and cheaper) greyscale LCD was fine.

Some solders also may have problems at very low temperatures
- if my
memory serves me right, lead has a phase change that
can exacerbate dry
joints in sub-zero temperatures. Connectors are also
a possible source
of problems, especially if exposed to vibration and
temperature
extremes.

Mike


On Nov 28, 5:18 pm, Marc Ramsey wrote:
wrote:
Is it true or just an 'old wives tale ' ?

For several years now I've removed all the instruments
with liquid
crystal displays ( LCD's) from my sailplane on the
advice I got from an
'expert ' some years ago . I was told that if you
store the glider with
instruments in an outside hangar where the temperature
drops to below
-20F at times , then that is very hard on the LCD's
. I did in fact
have an old Garmin start up in the Spring one year
after winter
storage, the screen turned brown then expired .The
specifications on modern LCDs vary, but typically the
low end of the
storage temperature range is usually somewhere in
the range -40C
(-40F) to -20C (-4F). High end is generally 80C (176F).

Marc

I wondered about this, researched it to a limited extent and then
thought - why take a chance? Not only is the cold a potential problem
but moisture etc. has a potential for causing problems as well. I
bought a quick-connect for all the pitot/static tubes on the panel and
installed a quick-connect for all the electrical wires leading to the
panel. When the glider comes home for the season, the panel comes out
of the glider and goes in the house. Takes about 5 minutes and the cold
and moisture hasn't caused a problem yet!

wrote:
Is it true or just an "old wives tale " ?

For several years now I've removed all the instruments with liquid
crystal displays ( LCD's) from my sailplane on the advice I got from an
"expert " some years ago . I was told that if you store the glider with
instruments in an outside hangar where the temperature drops to below
-20F at times , then that is very hard on the LCD's . I did in fact
have an old Garmin start up in the Spring one year after winter
storage, the screen turned brown then expired .

Thanks ,

Ron Clarke.

Jay wrote:
I wondered about this, researched it to a limited extent and then
thought - why take a chance? Not only is the cold a potential problem
but moisture etc. has a potential for causing problems as well. I
bought a quick-connect for all the pitot/static tubes on the panel and
installed a quick-connect for all the electrical wires leading to the
panel. When the glider comes home for the season, the panel comes out
of the glider and goes in the house. Takes about 5 minutes and the cold
and moisture hasn't caused a problem yet!

The cold and moisture may no longer cause a problem, but from my
experience, the quick connect eventually will. The last time I tried
one, it lasted a couple of seasons, then started to leak. These days, I
put an inline connector at the end all of the tubes, then use short
pieces of tubing to connect to the instruments, which get thrown away
every time I disconnect them...

Marc

Marc,
Good point - I do a static drawdown each year when I do the annual (I
have the equipment so what the heck). When it starts to leak I'll
probably change over to your method.

Marc Ramsey wrote:

The cold and moisture may no longer cause a problem, but from my
experience, the quick connect eventually will. The last time I tried
one, it lasted a couple of seasons, then started to leak. These days, I
put an inline connector at the end all of the tubes, then use short
pieces of tubing to connect to the instruments, which get thrown away
every time I disconnect them...

Marc

Quick connects are practical devices, who may also save a few embarrassing
(potential dangerous?) faulty connections. -But they require maintenance:
Silicone for the rubber parts, and careful cleaning of the threading at
every assembly will keep them going for years. I found that the ones with
plastic/metal threading will accumulate dust/debris from the plastic part,
eventually preventing an airtight fit.

Happy soaring,
Lars Peder

DG-600 EE, Denmark



"Jay" wrote in message
oups.com...
Marc,
Good point - I do a static drawdown each year when I do the annual (I
have the equipment so what the heck). When it starts to leak I'll
probably change over to your method.

Marc Ramsey wrote:

The cold and moisture may no longer cause a problem, but from my
experience, the quick connect eventually will. The last time I tried
one, it lasted a couple of seasons, then started to leak. These days, I
put an inline connector at the end all of the tubes, then use short
pieces of tubing to connect to the instruments, which get thrown away
every time I disconnect them...

Marc

Marc Ramsey wrote:
Jay wrote:
I wondered about this, researched it to a limited extent and then
thought - why take a chance? Not only is the cold a potential problem
but moisture etc. has a potential for causing problems as well. I
bought a quick-connect for all the pitot/static tubes on the panel and
installed a quick-connect for all the electrical wires leading to the
panel. When the glider comes home for the season, the panel comes out
of the glider and goes in the house. Takes about 5 minutes and the cold
and moisture hasn't caused a problem yet!

The cold and moisture may no longer cause a problem, but from my
experience, the quick connect eventually will. The last time I tried
one, it lasted a couple of seasons, then started to leak. These days, I
put an inline connector at the end all of the tubes, then use short
pieces of tubing to connect to the instruments, which get thrown away
every time I disconnect them...

I've switched over to silicone tubing for the instrument connections,
like the type that comes with a Cambridge 302. Cambridge will sell it to
you, as well as McMaster-Carr (probably cheaper). It's easy to install,
easy to remove, and retains this ease even after years of 100+ deg F
summers and 10 deg F winters. The factory glider tubing from the
pitot/static/etc is still the clear plastic stuff, so I use an inline
connector to the silicone tubing.


--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org