Volt & Amp Meters:




Volt & Amp meters:

Photos below of meters purchased on ebay.



Can be purchased at various suppliers on the internet, www.ebay.com and www.mpja.com.  These meters will generally come in two types, one that is powered off the voltage it's monitoring and the other is one that requires a separate external DC power supply (typically 5v): 

At www.mpja.com, to to PANEL METERS -> DIGITAL PANEL METERS -> Model 12308 ME

http://www.mpja.com/productview.asp?product=12308 ME

To wire, follow the instructions provided and/or see below.


Note: You must get separate power supplies to power the volt and amp meters.  Do not use a common power supply to power both.




Can be purchased from various suppliers on the internet and www.ebay.com.  You will also need a shunt of appropriate amp capacity for the power supply you will be using.



5V DC Meter Power supplies:

Can be purchased through www.mpja.com .

Power supplies (various Wall plug types):

A 5v DC I've personally purchased:
Under Power supplies -> Plug supplies -> Model 16172 PS
http://www.mpja.com/productview.asp?product=16172 PS



How to install the meters:  (VERY IMPORTANT, MUST READ)

As stated before, it is critical that you use a separate power supply for the volt meter(s) and a separate one for the ammeter(s).   You can power multiple voltmeters with a single 5v power supply and multiple ammeters with a single power supply.



The voltmeters have two separate pairs of board contacts on the back that are clearly marked to indicate which set is for the + & - of the 5v power supply and which is for the + & - for the sense input from the power supply that is to be monitored.  Simply solder the correct wire connections from the 5v power supply and power supply (monitored) to the correct locations and you are good to go.



The Ammeter is marked to show the proper polarity of the pins on the back for the 5v supply (and that it is for the 5v input), the other sense side has a + and - designation and the + goes on the side of the shunt that connects to the track and the - goes on the other side of the shunt that runs back to the power supply.  It is very important that you confirm whether the shunt needs to be installed in the + or - wire between the track and power supply.  Most if not all will need to be installed in the - wire and if you install in the + wire, it can damage the meter.

5v Power supplies:

These will typically come with a single round plug on the end for use in some standard device they were intended for.  Simply cut that connector off, plug into an outlet and probe with a voltmeter to determine which wire is + and which is -.  This is very important as you can damage your meter if hooked up incorrectly!  Next, strip back the insulation and solder to back of the voltmeter or connect to the provided wires of the ammeter.


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