NABCEP PV Installer Exam
4 main types of electrical injuries electrocution (death due to electrical shock), electrical shock, burns, and falls
current movement of electrical charge
voltage Measure of electrical force
circuit a complete path for the flow of current
You will receive a shock if you touch two wires at different voltages at the same time.
ground a physical electrical connection to the earth
energized (live, "hot") similar terms meaning that a voltage is present that can cause a current, so there is
a possibility of getting shocked
conductor material in which an electrical current moves easily
neutral at ground potential (0 volts) because of a connection to ground
if you touch a live wire and are grounded at the same time. You will receive a shock
When a circuit, electrical component, or equipment is a potential shock hazard is present.
energized
ampere (amp) the unit used to measure current
milliampere (milliamp or mA) 1/1,000 of an ampere
shocking current electrical current that passes through a part of the body
You will be hurt more if you can't let go of a tool giving a shock.
, NABCEP PV Installer Exam
The longer the shock the greater the injury.
1 milliamp Just a faint tingle.
5 milliamps Slight shock felt. Disturbing, but not painful. Most people can "let go." However,
strong involuntary movements can cause injuries.
6-25 milliamps (women)†Painful shock. Muscular control is lost. This is the range where "freezing
9-30 milliamps (men) currents" start. It may not be possible to "let go."
50-150 milliamps Extremely painful shock, respiratory arrest (breathing stops), severe muscle
contractions. Flexor muscles may cause holding on; extensor muscles may
cause intense pushing away. Death is possible.
1,000-4,300 milliamps (1-4.3 amps) Ventricular fibrillation (heart pumping action not rhythmic) occurs. Muscles contract;
nerve damage occurs. Death is likely.
10,000 milliamps Cardiac arrest and severe burns occur. Death is probable.
(10 amps)
15,000 milliamps Lowest overcurrent at which a typical fuse or circuit breaker opens a circuit!
(15 amps)
Severity of shock depends on voltage, amperage, and resist- ance
resistance a material's ability to decrease or stop electrical current
ohm unit of measurement for electrical resistance
Lower resistance causes greater currents.
NEC—National Electrical Code a comprehensive listing of practices to protect workers and equipment from
electrical hazards such as fire and electrocution
arc-blast explosive release of molten material from equipment caused by high-amperage arcs
arcing the luminous electrical dis- charge (bright, electrical sparking) through the air that
occurs when high voltages exist across a gap between conductors
4 main types of electrical injuries electrocution (death due to electrical shock), electrical shock, burns, and falls
current movement of electrical charge
voltage Measure of electrical force
circuit a complete path for the flow of current
You will receive a shock if you touch two wires at different voltages at the same time.
ground a physical electrical connection to the earth
energized (live, "hot") similar terms meaning that a voltage is present that can cause a current, so there is
a possibility of getting shocked
conductor material in which an electrical current moves easily
neutral at ground potential (0 volts) because of a connection to ground
if you touch a live wire and are grounded at the same time. You will receive a shock
When a circuit, electrical component, or equipment is a potential shock hazard is present.
energized
ampere (amp) the unit used to measure current
milliampere (milliamp or mA) 1/1,000 of an ampere
shocking current electrical current that passes through a part of the body
You will be hurt more if you can't let go of a tool giving a shock.
, NABCEP PV Installer Exam
The longer the shock the greater the injury.
1 milliamp Just a faint tingle.
5 milliamps Slight shock felt. Disturbing, but not painful. Most people can "let go." However,
strong involuntary movements can cause injuries.
6-25 milliamps (women)†Painful shock. Muscular control is lost. This is the range where "freezing
9-30 milliamps (men) currents" start. It may not be possible to "let go."
50-150 milliamps Extremely painful shock, respiratory arrest (breathing stops), severe muscle
contractions. Flexor muscles may cause holding on; extensor muscles may
cause intense pushing away. Death is possible.
1,000-4,300 milliamps (1-4.3 amps) Ventricular fibrillation (heart pumping action not rhythmic) occurs. Muscles contract;
nerve damage occurs. Death is likely.
10,000 milliamps Cardiac arrest and severe burns occur. Death is probable.
(10 amps)
15,000 milliamps Lowest overcurrent at which a typical fuse or circuit breaker opens a circuit!
(15 amps)
Severity of shock depends on voltage, amperage, and resist- ance
resistance a material's ability to decrease or stop electrical current
ohm unit of measurement for electrical resistance
Lower resistance causes greater currents.
NEC—National Electrical Code a comprehensive listing of practices to protect workers and equipment from
electrical hazards such as fire and electrocution
arc-blast explosive release of molten material from equipment caused by high-amperage arcs
arcing the luminous electrical dis- charge (bright, electrical sparking) through the air that
occurs when high voltages exist across a gap between conductors
