2006-09-17 16:28:25 · 3 answers · asked by sumone^^ 3 in Science & Mathematics ➔ Engineering
You need a voltmeter. Polarity test has to do with the positive and negative terminals on your voltmeter. Put the setting on DC (direct current) and then "supose" which wire (or outlet, depending on what you are testing) is the positive one... put the positive terminal to your positive wire and your negative terminal to your negative wire. If the reading is positive... you are right! If the reading is negative, polartiy is reversed!
For continuity, take your voltmeter and put one end of the wire to one terminal, and the other to the other terminal... then turn the scale of the voltmeter to the minimum... if it reads 0V... continuity is OK... if the reading is "trembling" or oscilating between several numbers, you have an open circuit! (you might want to confirm this by using an ohmeter... if it reads 0 ohms, you have a continuous wire, if it goes out of scale, you have an open circuit)
2006-09-17 16:34:28 · answer #1 · answered by kc 2 · 0⤊ 0⤋
In both instances, a volt/ohm meter will be used.
The continuity test is done with the meter set to Ohms. And a low reading will indicate good continuity and a high reading will indicate a high resistance or no continuity.
The polarity of the DC voltage can be determined with the meter on the DC VOLT scale - the red lead indicating a positive polarity and the black lead (common jack) a negative one.
2006-09-17 16:36:52 · answer #2 · answered by LeAnne 7 · 0⤊ 0⤋
I'll go with what kc said, but I just want to add one more piece. When doing polarity checking you may need to switch the voltmeter to the diode checking setting in order to push the voltage high enough to get through a diode that you would be checking.
2006-09-17 16:37:47 · answer #3 · answered by rscanner 6 · 0⤊ 0⤋