Ammeters

Problem Statement

 * Replace 1K resistor in voltmeter as converted ammeter.
 * Learn how to use circuit lab.
 * Use circuit lab to find the resistors.

voltmeter,ammeter and schematic review
Demonstrate how voltmeter works: Open voltmeter check inside
 * It is easy to solder on the resistor and put the meter back together.


 * Figure out how to convert voltmeter to ammeter.
 * Here is a solution. Conversion of voltmeter to ammeter
 * Following this pdf instruction to find the resistor.


 * Where to place the ammeter in the power supply?
 * Figure out why need a shunt resistance.
 * Figure out why change series connection to parallel connection

The Design Process

 * Open up the voltmeter.
 * unscrew the front cover.Front view123.JPG
 * unscrew the back cover.Back view.JPG
 * take out the inner part,then will see the resistance on back. Voltmeter inner part.JPGVoltmeter resistance.jpg
 * change voltmeter's resistance to a smaller shunt resistance.(1ohm or <1 ohm,need to confirm)
 * put shunt resistance in parallel connect.
 * Solution:replace 1ohm resistor with voltmeter's resistor.

Experiment prototypes and tests need for design

 * We will test the ammeter and use it in the power supply.