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COLD weather... — Parallax Forums

COLD weather...

ArchiverArchiver Posts: 46,084
edited 2003-04-01 22:37 in General Discussion
Hello Stampers, I was wondering if any stampers in very cold areas would be
able to help me with using an LCD outdoors at temperatures down to -40c. I
am in Australia and we never even hear of these temperatures, but I know
some of you Canadian or US people would (I dont know how) live at times in
these extremes. (I dont know why you dont move down here if its that cold !)

I have been asked to make a stamp based project which has a keypad and LCD
which will apparently be subjected to extremes of that temperature.

I have tested the unit in my deep freeze which I think only gets down to
about -20c, and the system works fine except the LCD is very slow to react.
It is useable, but if it was at -40c I dont know what would happen.

Does anyone have any tips for warming the LCD etc ?, or any other
information that may help ?.

Thanks in advance,
Chris - Western Australia (very cold today... +24c)

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-04-01 15:38
    Warming the LCD should not be a problem if you have enought power to
    do so. Here in New Jersey, we get cold, about 10deg F above zero,
    but not much less (often)

    A simple well insulated and heated enclosure would be wanted and in
    those termpeatures, you might want to check on battery specs. An
    option might be that a button press will start a warming cycle that
    will heat the display for a minute while the operator waits.

    another option might be a LED that responds with a push button ?

    My experiance with low temperatures was with a HOBO data logger. as
    it approached 25 deg F, the readings died. it resolved about 80% of
    the reading in the first 5 minutes, but after a half hour, the
    reading was still moving towards the actual temperature. I never
    was able to monitor actual changes at temperature due to the lack of
    response. I did have the electronics in 70 deg F room with a sensor
    in the fridge.

    My intention was to monitor the refridgerator coil cycling on an off.

    When selecting a sensor, make sure that it is capable of not only
    seeing the temperatures you want, but also to respond to the accuracy
    you are looking for at those temperaturs and in the time frame you
    need.

    Dave



    --- In basicstamps@yahoogroups.com, "Chris Anderson" <fuel@b...>
    wrote:
    > Hello Stampers, I was wondering if any stampers in very cold areas
    would be
    > able to help me with using an LCD outdoors at temperatures down to -
    40c. I
    > am in Australia and we never even hear of these temperatures, but I
    know
    > some of you Canadian or US people would (I dont know how) live at
    times in
    > these extremes. (I dont know why you dont move down here if its
    that cold !)
    >
    > I have been asked to make a stamp based project which has a keypad
    and LCD
    > which will apparently be subjected to extremes of that temperature.
    >
    > I have tested the unit in my deep freeze which I think only gets
    down to
    > about -20c, and the system works fine except the LCD is very slow
    to react.
    > It is useable, but if it was at -40c I dont know what would happen.
    >
    > Does anyone have any tips for warming the LCD etc ?, or any other
    > information that may help ?.
    >
    > Thanks in advance,
    > Chris - Western Australia (very cold today... +24c)
  • ArchiverArchiver Posts: 46,084
    edited 2003-04-01 16:27
    The equipment I used to support was designed for outdoor use with an
    extended-temperature LCD. One engineer used a special heater that warmed the
    inside of the cabinet, while the other designed his product to use a cheap
    power resistor mounted behind the LCD. Both used a temperature sensor IC to
    determine when heat was needed.

    If the electronics will be exposed to people with the cabinet open, be sure
    to use some sort of shield to prevent burns. Also, an LED to indicate when
    the heater is on will aid troubleshooting.

    Original Message

    > Warming the LCD should not be a problem if you have enought power to
    > do so. Here in New Jersey, we get cold, about 10deg F above zero,
    > but not much less (often)
    >
    > A simple well insulated and heated enclosure would be wanted and in
    > those termpeatures, you might want to check on battery specs. An
    > option might be that a button press will start a warming cycle that
    > will heat the display for a minute while the operator waits.
    >
    > another option might be a LED that responds with a push button ?
  • ArchiverArchiver Posts: 46,084
    edited 2003-04-01 16:48
    Another thing that works really well for cold temps
    and is one of the most inexpensive items one can buy
    is a Styrofoam cooler. I used one of these with some
    LCD containing instruments. When I wanted to read
    the display I would insert one of those self heating
    packs they sell for camping. In about 15 minutes
    the enclosure was warm and the LCD worked down to -40
    F.

    Andy
    Original Message
    From: "Rodent" <daweasel@s...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, April 01, 2003 15:27
    Subject: Re: [noparse][[/noparse]basicstamps] Re: COLD weather...


    > The equipment I used to support was designed for outdoor use with an
    > extended-temperature LCD. One engineer used a special heater that warmed
    the
    > inside of the cabinet, while the other designed his product to use a cheap
    > power resistor mounted behind the LCD. Both used a temperature sensor IC
    to
    > determine when heat was needed.
    >
    > If the electronics will be exposed to people with the cabinet open, be
    sure
    > to use some sort of shield to prevent burns. Also, an LED to indicate when
    > the heater is on will aid troubleshooting.
    >
    >
    Original Message
    >
    > > Warming the LCD should not be a problem if you have enought power to
    > > do so. Here in New Jersey, we get cold, about 10deg F above zero,
    > > but not much less (often)
    > >
    > > A simple well insulated and heated enclosure would be wanted and in
    > > those termpeatures, you might want to check on battery specs. An
    > > option might be that a button press will start a warming cycle that
    > > will heat the display for a minute while the operator waits.
    > >
    > > another option might be a LED that responds with a push button ?
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-04-01 22:37
    A while back, I got some flexible little heating elements from Electronic
    Goldmine. They are like thick tape, and they came in a pack of different
    sizes. They have sticky on the back to adhere. I haven't really played with
    them, but they might make a nice LCD warmer.

    Jonathan

    www.madlabs.info

    Original Message
    From: "ASHorn" <ashorn@e...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, April 01, 2003 7:48 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: COLD weather...


    > Another thing that works really well for cold temps
    > and is one of the most inexpensive items one can buy
    > is a Styrofoam cooler. I used one of these with some
    > LCD containing instruments. When I wanted to read
    > the display I would insert one of those self heating
    > packs they sell for camping. In about 15 minutes
    > the enclosure was warm and the LCD worked down to -40
    > F.
    >
    > Andy
    >
    Original Message
    > From: "Rodent" <daweasel@s...>
    > To: <basicstamps@yahoogroups.com>
    > Sent: Tuesday, April 01, 2003 15:27
    > Subject: Re: [noparse][[/noparse]basicstamps] Re: COLD weather...
    >
    >
    > > The equipment I used to support was designed for outdoor use with an
    > > extended-temperature LCD. One engineer used a special heater that warmed
    > the
    > > inside of the cabinet, while the other designed his product to use a
    cheap
    > > power resistor mounted behind the LCD. Both used a temperature sensor IC
    > to
    > > determine when heat was needed.
    > >
    > > If the electronics will be exposed to people with the cabinet open, be
    > sure
    > > to use some sort of shield to prevent burns. Also, an LED to indicate
    when
    > > the heater is on will aid troubleshooting.
    > >
    > >
    Original Message
    > >
    > > > Warming the LCD should not be a problem if you have enought power to
    > > > do so. Here in New Jersey, we get cold, about 10deg F above zero,
    > > > but not much less (often)
    > > >
    > > > A simple well insulated and heated enclosure would be wanted and in
    > > > those termpeatures, you might want to check on battery specs. An
    > > > option might be that a button press will start a warming cycle that
    > > > will heat the display for a minute while the operator waits.
    > > >
    > > > another option might be a LED that responds with a push button ?
    > >
    > >
    > >
    > >
    > > To UNSUBSCRIBE, just send mail to:
    > > basicstamps-unsubscribe@yahoogroups.com
    > > from the same email address that you subscribed. Text in the Subject
    and
    > Body of the message will be ignored.
    > >
    > >
    > > Your use of Yahoo! Groups is subject to
    http://docs.yahoo.com/info/terms/
    > >
    > >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
    >
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