Chapter 20&23 Final
The disconnect for motor-driven appliances having a motor of greater than ____ must be within sight of the appliance.
1/8 hp
The disconnecting means and branch circuit conductors for an electric furnace shall be sized not less than ____ percent of the total nameplate load shown on the furnace.
125
The total load of an air conditioner shall not exceed ____ percent of the rating of a branch circuit that also supplies lighting.
50
When a central air-conditioning unit label states "maximum fuse size 50 amperes," what type of circuit-breaker is permitted to provide running overload protection?
50-ampere circuit-breaker
A feeder or service neutral load can be figured at ____ of the load on the ungrounded conductors for ranges and ovens.
70 percent
The total load of an air conditioner shall not exceed ____ percent of the rating of a separate branch circuit.
80
All of the following are acceptable disconnecting means for appliances, except for ____.
a HP-rated switch
A line-voltage thermostat used to control household heating apparatus rated 240 volts disconnects ____.
both ungrounded conductors
A "unit switch" used as a disconnecting means for an appliance shall ____.
interrupt all ungrounded circuit conductors
Supply voltage affects the heat output of electric heating appliances. Although the appliance nameplate will show the kilowatt rating at a nominal voltage, such as 208 or 240, actual output depends on the voltage available at the terminal of the equipment. The ____ the voltage, the ____ the heat output.
lower, lower
When an appliance is not marked with its maximum overcurrent protection, the branch circuit protection device is sized according to ____.
the ampacity of the branch circuit conductors
On circuits supplying cord-and-plug connected air conditioners, the branch circuit overcurrent protective device rating is not permitted to exceed ____.
the ampacity of the branch circuit conductors, recept and A/C connection
The NEC permits flexible cords to be used to supply appliances where ____.
there are connections & ready for removal to repair
NEC 422.12 on central heating equipment requires ____.
to be on a separate branch circuit
Where a flexible cord is used to supply a room air conditioner, the length of the flexible cord shall not exceed ____ for 120-volt units.
10 ft (3.0 m)
When a separate branch-circuit is run to a wall mounted oven, or to a counter-mounted cooking unit, the branch circuit size is based on ____ of the nameplate rating of the appliance.
100 percent
The Article that covers cord-and-plug connected air conditioners is ____.
Article 440
On all types and ratings of receptacles, the grounding blade is ____ than the others to insure that it makes its connection before the grounded conductors do and breaks its connection after they do (first make-last break).
larger
Household cooking device demand factors shown in Table 220.55 are normally ____ than the appliance nameplate rating.
less
Baseboard heating units can be controlled by ____.
line-voltage & low voltage thermostats