I mean that with a divider of 2.2k + 10k, 10V at the midpoint corresponds to
12.2V across the entirety. Similarly, 4.7k+10k will give you 14.7 / 10 * 10V =
14.7V range (10V at midpoint is 14.7V across entirety).
C
> On Feb 21, 2015, at 11:53 AM, Peter Hollenbeck <pwhb...@gmail.com> wrote:
>
> Colin,
> Sorry about my feeble attempt at ASCII art. My divider consists of two
> connected 1K resistors. Battery plus and minus are connected at the ends.
> MS-TV red wire connected at the center. MS-TV black wire connected at same
> place as battery minus.
>
> I will try your suggestion. What do you mean "a range of 12.2V"?
> The battery bank voltage will range from about 11 to 13.5 so that is the
> range I would like to measure.
> Thanks,
> Peter
>
>
>
>> On Sat, Feb 21, 2015 at 11:40 AM, Colin Reese <colin.re...@gmail.com> wrote:
>> I unfortunately cannot read your ascii art, which in itself is disappointing.
>>
>> 2k is a bit low for a divider - you'll get standby current of 6mA. You
>> should also try optimizing the split to fit the range you can measure. So
>> you'd want a ratio of R2/Rtotal =measured range/ measurable range. So
>> 2.2k/10k would give you standby of <1mA and a range of 12.2V.
>>
>> As for diagnosing your actual problem, I'd get out a meter or scope to
>> determine which end your issue is on.
>>
>> Colin
>>
>>
>>
>>
>> > On Feb 21, 2015, at 11:29 AM, Peter Hollenbeck <pwhb...@gmail.com> wrote:
>> >
>> > I am using a LinkUSB and an MS-TV to read voltage from a 12 volt system.
>> > The MS-TV is limited to 10 volts so a made a voltage divider. I know next
>> > to nothing about electronics. Two weeks ago, with a test 12v power supply
>> > I played with various resistor values, from 1K to 1M. The 1K resistors
>> > appeared to give the best reading, about 6 volts. The higher the value the
>> > lower the output. Now, working with a real 12v battery system I am getting
>> > values ranging all over - .1, .82, .07, 10+, and rarely something
>> > reasonable, like 6.6.Within several minutes I just got 0.7 followed by
>> > 9.75. An inverter connected to the battery bank displays 12.1 volts and
>> > the output from my program shows .71 volts.
>> >
>> > My divider looks like this:
>> >
>> > 1K 1K
>> > ---------^v^v------------^v^v-----------------------
>> > | | | |
>> > | | | |
>> > | | | |
>> > | | | |
>> > battery (+) | | battery (-)
>> > MS-TV MS-TV
>> > red wire black wire
>> >
>> > I sure would appreciate suggestions.
>> > Thank you,
>> > Peter
>> >
>> > ------------------------------------------------------------------------------
>> > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
>> > from Actuate! Instantly Supercharge Your Business Reports and Dashboards
>> > with Interactivity, Sharing, Native Excel Exports, App Integration & more
>> > Get technology previously reserved for billion-dollar corporations, FREE
>> > http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
>> > _______________________________________________
>> > Owfs-developers mailing list
>> > Owfs-developers@lists.sourceforge.net
>> > https://lists.sourceforge.net/lists/listinfo/owfs-developers
>>
>> ------------------------------------------------------------------------------
>> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
>> from Actuate! Instantly Supercharge Your Business Reports and Dashboards
>> with Interactivity, Sharing, Native Excel Exports, App Integration & more
>> Get technology previously reserved for billion-dollar corporations, FREE
>> http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
>> _______________________________________________
>> Owfs-developers mailing list
>> Owfs-developers@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/owfs-developers
>
> ------------------------------------------------------------------------------
> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
> from Actuate! Instantly Supercharge Your Business Reports and Dashboards
> with Interactivity, Sharing, Native Excel Exports, App Integration & more
> Get technology previously reserved for billion-dollar corporations, FREE
> http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
> _______________________________________________
> Owfs-developers mailing list
> Owfs-developers@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/owfs-developers
------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
_______________________________________________
Owfs-developers mailing list
Owfs-developers@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/owfs-developers