Current Events
Recessed luminaires are likely to be found in a
ceiling
The NEC-lists how many classification(s) of hazardous atmospheres?
3
The minimum interrupting rating of branch circuit listed fuses is
Most control transformers are
dry-type, step-down
What is Article 240 about?
Overcurrent Protection
Following the loss of normal power, an exit luminaire must remain lit for
90 minutes
How many group(s) are listed under Class I, Division 1?
4
A plug fuse is typically used in a
branch circuit
The power factor of a circuit can be improved by increasing the
capacitance
What article is Grounding and Bonding?
Article 250
Time clocks are often used with
photo sensors
When installing switches or other arc-producing apparatus in Class I, Division 1 locations, within what distance of the switch (or other apparatus) must sealing fittings be installed?
18''
The full-load current rating of a 150kVA, three-phase transformer operating at 240V is
362A
The three basic types of iron core transformers are
closed core, open core, and shell
What type of equipment changes dc to ac?
Inverter
A class of lighting that distributes 90% to 100% of light downward is
Direct
When rigid metal conduit is required in hazardous locations, the threads must be cut at
3/4" taper per foot
A circuit breaker that trips instantly or fails to reset is most likely the result of
a short circuit
The main purpose of a transformer is to
change the output voltage
What does Ampacity mean?
the MAXIMUM current, (AMPS) that a conductor can carry continuously under the conditions of use without exceeding it temperature rating
A cobra-head luminaire may be used for
roadway lighting
The main purpose of a union in conduit runs is to
facilitate the installation and removal of equipment
The maximum voltage that a piece of equipment can withstand is known as its
basic impulse insulation level (BIL)
The three parts of a basic transformer are
the primary winding, secondary winding, and core
What Article is about Energy Storage Systems
Article 706