Troubleshooting

• A voltmeter is a device that is used to measure voltage across two points , it is connected in parallel with the circuit.
• An ammeter is a device used to measure electric current, it is connected in series with the circuit and is more accurate
• AC Voltage , DC voltage , Resistance ( Ohms ) , continuity , and current ( amps ) are the standard meter readings on a multimeter.
• OL on a multimeter means “ Open Loop “ or “ Open Line “ which means no continuity ( no complete path )
• Continuity is the presence of a complete path . A circuit is complete when it’s switch is closed .
• When testing for continuity , make sure the power is off and the component is disconnected from its circuit before the leads touch it . 
• When testing for continuity , Separated test probes should show OL and OHM( resistance) 
• When testing for continuity, and the leads make contact with each other the meter should show less than 1 ohm .
• Conductors are materials that offer very little resistance where electrons can move easily 
• Examples of a conductor are silver , copper , gold , aluminum 
• Insulators are materials with high resistance and restrict the flow of electrons 
• Examples of a insulator is rubber , paper , glass , and plastic 
• Resistance is a measure of the opposition to current flow in an electrical unit
• Voltage , or potential difference , is the pressure in a electrical system 
• • DC is direct current , which flows in only one direction through a conductor
• AC is alternating current , which changes direction 60 times a second
• You should only measure continuity / resistance (ohms) when you are disconnected from a circuit 
• When your meter is on Continuity / Resistance mode . Your only able to test continuity when the a switch is on (closed contacts ), and your only able to test resistance when the switch is off ( open contacts )
• Zero [0] ohms is a solid metal connection with no resistance , which is impossible . 
• OL ( Open Line ) means very high amounts of resistance between the leads 
• Before testing any circuit , always know what voltage  expected and if your meter is rated properly. 
• Resistance (Ohms) / Continuity should never be measured with live circuits . 
• When connecting test probes … The test leads should go Neutral / Ground [ Black ] first, then hot [Red ] last 
• When probes are connected for testing , if you disconnect the Neutral / Ground [ Black ] from a circuit the test probe becomes hot .