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solar stamp

ArchiverArchiver Posts: 46,084
edited 2000-08-13 01:35 in General Discussion
hi all

I am trying to do the solar stamp project but i seem to have a hit a snag. I
have the super cap attached to VDD and it charges in about 30 secs. The
solar panel is attached to the 9 volt stubs on the carrier board. I get the
impression from the manual it should take longer. And when the stamp is
running off the cap it discharges to 4 v and the leds go out. This takes
about a minute. I read in the manual that at 4 volts the stamp resets but in
the application it says they were running at 3.65 volts. I dont have the
same solar panel used in the application as i couldnt find one. Also they
mention a solar battery but just show a solar panel. are these two the same?

my project is slightly different from the one in the book. I want a led to
be on
while the stamp sleeps for 6 hrs then light another led. Does having the led
on constantly really suck up that much power?
thanks for the help

jeff

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2000-08-11 07:23
    Hi Jeff;

    I'm new to this Basic Stamp stuff myself. However I've been in
    electronices a while. Do you lnow how much the battery is drawing
    in charge mode ? Depending on the size of your solar cell, it could be
    only
    ma (milliamps), an LED draws a few ma itself, Not knowing all
    the figures I would guess that the LED might be taking the better part
    of the charge current leaving little or none for the charging of the
    battery.
    A good way to test this is turn the LED off for a charge cycle and see if
    things get better. Also using solar charging, it might be a good idea to
    charge the battery on a regular charger to start off with, if you were not
    getting a good charge by now the battery is most likly pretty weak.
    Of course these are all just ideas, but thats my 2 cents worth.
    Let us know how ya make out.

    kc7zmz
    Frank
    Original Message
    From: <TETTRA@a...>
    To: <basicstamps@egroups.com>
    Sent: Thursday, August 10, 2000 4:14 PM
    Subject: [noparse][[/noparse]basicstamps] solar stamp


    >
    >
    > hi all
    >
    > I am trying to do the solar stamp project but i seem to have a hit a snag.
    I
    > have the super cap attached to VDD and it charges in about 30 secs. The
    > solar panel is attached to the 9 volt stubs on the carrier board. I get
    the
    > impression from the manual it should take longer. And when the stamp is
    > running off the cap it discharges to 4 v and the leds go out. This takes
    > about a minute. I read in the manual that at 4 volts the stamp resets but
    in
    > the application it says they were running at 3.65 volts. I dont have the
    > same solar panel used in the application as i couldnt find one. Also
    they
    > mention a solar battery but just show a solar panel. are these two the
    same?
    >
    > my project is slightly different from the one in the book. I want a led
    to
    > be on
    > while the stamp sleeps for 6 hrs then light another led. Does having the
    led
    > on constantly really suck up that much power?
    > thanks for the help
    >
    > jeff
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2000-08-13 01:35
    Hello,

    Solar projects usually require careful reduction of all power consumed.
    LED's often draw from 1 to 20 milliamps depending on the series resistor
    used, and are one area of large power usage as compared to the stamp. You
    might try using a very high brightness LED, and setting the current very low
    (0.1 to 0.2mA) with the proper series resistor to extend run-time. Another
    problem is using the onboard 5VDC voltage regulator. The onboard regulator
    is a linear regulator that is not very energy efficient. Use of a switching
    regulator to provide the 5 volts can reduce power consumption. Let me know
    if you need parts for an energy efficient 5VDC switching regulator circuit,
    etc.

    Sincerely,

    Charles Page, President, Technology Electronics, Ltd.
    www.technologykit.com

    Original Message
    From: TETTRA@a... <TETTRA@a...>
    To: basicstamps@egroups.com <basicstamps@egroups.com>
    Date: Thursday, August 10, 2000 7:15 PM
    Subject: [noparse][[/noparse]basicstamps] solar stamp


    >
    >
    > hi all
    >
    >I am trying to do the solar stamp project but i seem to have a hit a snag.
    I
    >have the super cap attached to VDD and it charges in about 30 secs. The
    >solar panel is attached to the 9 volt stubs on the carrier board. I get the
    >impression from the manual it should take longer. And when the stamp is
    >running off the cap it discharges to 4 v and the leds go out. This takes
    >about a minute. I read in the manual that at 4 volts the stamp resets but
    in
    >the application it says they were running at 3.65 volts. I dont have the
    >same solar panel used in the application as i couldnt find one. Also
    they
    >mention a solar battery but just show a solar panel. are these two the
    same?
    >
    >my project is slightly different from the one in the book. I want a led to
    >be on
    >while the stamp sleeps for 6 hrs then light another led. Does having the
    led
    >on constantly really suck up that much power?
    >thanks for the help
    >
    >jeff
    >
    >
    >
    >
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