Breaking News
Comments
Newest First | Oldest First | Threaded View
<<   <   Page 11 / 11
mhrackin
User Rank
Author
Meter Guts
mhrackin   8/22/2014 2:31:08 PM
NO RATINGS
ALL D'Arsonval (moving coil) meters are the best type, and the basic design is ALWAYS a DC current meter.  Many of these have a movement wiith a full-scale range of either 50uaDC (the expensive ones) or 1maDC.  These can be made to display other functions or ranges by connecting either a shunt resistor (for higher FS current) or series resistor (multiplier) to change to a DC voltmater.  For AC, the meter may be a moving-vane (e.g. Shurite type, usually relatively cheap) design which will work for AC or DC (although scale factor may be off), or uses a rectifier (typically bridge) along with a multipler or shunt.  VERY often, the shunt, multipler, and/or rectifier is EXTERNAL, so you CAN'T go by the faceplate in determining the meter configuration!  It's pretty easy to tell, thpough, with  a DC power supply, some resistors, and a multimeter.  Assume it's a "naked" DC milli/micro-ammeter, connect the PSU, a suitable current-limiting resistor, and the multimeter (in ammeter mode) in series and see what the meter does when the PSU is turned on.  Ther rest of the process (and how to calculate appropriate shunt/multiplier values) is left as an exercise for the student!

antedeluvian
User Rank
Author
Realistic
antedeluvian   8/22/2014 2:16:08 PM
NO RATINGS
Max

One thing I'd vaguely considered was to sand the faceplate down (using very fine sandpaper), spray-paint it white, and then add the new annotations by hand using a very fine indelible marker. But the more I think about this, the more I think the result would look absolutely horrible

But more realistically Victorian! In my blog Touring as an Engineer, I mention the Pitt-Rivers Museum where the labels on the exhibits are either handwritten or written with a typewriter with a rather grungy ribbon.

 

DrQuine
User Rank
Author
New faceplates for analog meters
DrQuine   8/22/2014 2:08:35 PM
NO RATINGS
I recently purchased a replacement explosive gas sensor for a storage area and realized that the meter had been very neatly relabeled with the appropriate text. They were buying 0 - 20 ma gauges and then affixing new text on the meter faces for the application at hand.

<<   <   Page 11 / 11


Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Like Us on Facebook
Special Video Section
Protecting sensitive electronic circuitry from voltage ...
09:45
Watch as a web server authenticates or rejects a water ...
Protecting sensitive electronic circuitry from voltage ...
Watch as a web server authenticates or rejects a water ...
Protecting sensitive electronic circuitry from voltage ...
Power can be a gating factor in success or failure of ...
Get to market faster and connect your next product to the ...
00:44
See how microQSFP is setting a new standard for tomorrow’s ...
The LTC3649 step-down regulator combines key features of a ...
Once the base layer of a design has been taped out, making ...
In this short video we show an LED light demo to ...
The LTC2380-24 is a versatile 24-bit SAR ADC that combines ...
In this short video we show an LED light demo to ...
02:46
Wireless Power enables applications where it is difficult ...
07:41
LEDs are being used in current luxury model automotive ...
With design sizes expected to increase by 5X through 2020, ...
01:48
Linear Technology’s LT8330 and LT8331, two Low Quiescent ...
The quality and reliability of Mill-Max's two-piece ...
LED lighting is an important feature in today’s and future ...
05:27