What is the smallest voltmeter?
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From: Bruce W.1 on 31 Jan 2007 13:45 I'm looking for the very smallest -- panel mount -- LCD voltmeter. My Google searches have been dissapointing. The smallest I could find is about 2" wide. This will be part of a 12V bicycle light system. It will mount in a small box, probably on the handlebars. It's measurement range should be about 8 to 20 volts. A voltmeter is not complicated. I would think that one could easily be made in a 1/2" square. Does anyone know of a really tiny voltmeter? Thanks for your help.
From: David L. Jones on 31 Jan 2007 15:07 On Feb 1, 5:45 am, "Bruce W.1" <s...(a)noDirectEmail.com> wrote: > I'm looking for the very smallest -- panel mount -- LCD voltmeter. My > Google searches have been dissapointing. The smallest I could find is > about 2" wide. > > This will be part of a 12V bicycle light system. It will mount in a > small box, probably on the handlebars. It's measurement range should be > about 8 to 20 volts. > > A voltmeter is not complicated. I would think that one could easily be > made in a 1/2" square. > > Does anyone know of a really tiny voltmeter? > > Thanks for your help. Less than 1" wide: http://au.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=9932909 Standard 200mV FSD, just make your own input scaler. Dave :)
From: Bruce W.1 on 31 Jan 2007 16:03 David L. Jones wrote: > > Less than 1" wide: > http://au.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=9932909 > Standard 200mV FSD, just make your own input scaler. > > Dave :) > ================================================= Expensive little guy isn't it? My battery pack (12 C-cells) exceeds its [14VDC] voltage rating. BTW, I'm also building a Pulse Width Modulation circuit so I don't fry my 12VDC lightbulbs. This voltmeter will monitor its input and output voltage.
From: Jason von Nieda on 31 Jan 2007 16:09 Bruce W.1 wrote: > Expensive little guy isn't it? My battery pack (12 C-cells) exceeds its > [14VDC] voltage rating. > > BTW, I'm also building a Pulse Width Modulation circuit so I don't fry > my 12VDC lightbulbs. This voltmeter will monitor its input and output > voltage. Bruce, If you need to do voltage monitoring and PWM at the same time, I might recommend a AVR for the whole job. There might be cheaper/better/faster ways to do it, but you can get AVR microcontrollers for a few bucks that have PWM and ADC right on them. Use the ADC and a little resistor voltage divider to monitor your power. All the software development tools for AVRs are free, and you can build a programmer for them out of a parallel printer cable and a pair of wire cutters :) You may be completely familiar with AVRs and microcontrollers, but if not, feel free to drop me a line at jason(a)vonnieda.org if you want some tips. Jason
From: John Popelish on 31 Jan 2007 19:15
Bruce W.1 wrote: > I'm looking for the very smallest -- panel mount -- LCD voltmeter. My > Google searches have been dissapointing. The smallest I could find is > about 2" wide. > > This will be part of a 12V bicycle light system. It will mount in a > small box, probably on the handlebars. It's measurement range should be > about 8 to 20 volts. Here is the smallest I have used, from Digikey: http://rocky.digikey.com/WebLib/Martel/Web%20Data/DPM_1AS-BL.pdf Pretty spendy, though. You would have to scale the voltage down with a voltage divider. |