Basic Testers
This tool checks for voltage without touching the wire.
a non-contact voltage tester
This tool measures voltage, current, resistance, and continuity
a multimeter
This is the approximate voltage reading of a standard residential receptacle.
120 volts
This term refers to the positive and negative sides of a circuit when taking a measurement
polarity
This tester checks insulation quality in megohms.
insulation tester (Megger)
This tester plugs into a 120V outlet to check wiring conditions.
a receptacle tester
This type of meter uses a moving needle to display readings.
an analog multimeter
This setting is used on a multimeter when checking if a circuit is complete
Continuity
On a standard 120V receptacle, this slot is connected to the hot wire
short (narrow) slot
This tester measures the effectiveness of a grounding system.
an earth ground tester
This type of voltage tester vibrates when voltage is present.
a solenoid tester (Wiggy)
This meter uses jaws to measure current without touching bare conductors.
a clamp meter?
When measuring voltage, the red probe goes here
hot slot
On a standard 120V receptacle, this slot is connected to the neutral wire.
the long (wide) slot
This testing method is commonly used for a single ground rod.
the fall-of-potential method
This tester gives a numeric voltage reading and uses very little current.
a digital voltage tester
This is the common (black) port on a multimeter used for most measurements.
the COM port
This must be done before and after using a tester to ensure it works properly
test the tester on a known live circuit
If hot and neutral are reversed, this dangerous condition can occur even when a device is turned off.
the device still being energized
This tester ensures a 3-phase motor spins in the correct direction.
phase/motor rotation tester
This tester can be paired with another device to locate the correct breaker in a panel.
a wireless circuit breaker tester
This is why clamp meters are safer for high current measurements
they measure through insulation without direct contact
This happens if you cross probes while testing voltage.
a short circuit (which can damage the meter)
When using a multimeter, this is where the red and black leads should be placed for proper polarity when measuring voltage.
red to hot and black to neutral (or ground)
If a 3-phase motor runs backward, this simple fix corrects it.
swapping any two leads