When connecting a voltmeter into a DC circuit, what should be observed?
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Steam-Heating Boiler operated at pressures not exceeding ______ for steam
The lightening outlet installed at or near heating, air-conditioning and refrigeration equipment shall be controlled _______
What must be provided for all working spaces above service equipment, switchboards and panel boards?
Underground wiring shall be installed in which conduit?
Working space in rooms allocated for electrical equipment shall not be used for _______
A concealed conductor in electrical wiring means
Circuits are equipment operating at less than 50V shall have a lamp holders of rating not less than _______ watts.
Breathing Zone region shall be more than _______ from the walls of the space or from fixed air-conditioning equipment
Positive mechanical ventilation which provides a minimum of ______ complete air changes per hour shall be installed in limited spraying spaces
When an electrical circuit tested with ohmmeter, a open circuit is indicated by a reading of _______
The termination point of exhaust outlets and ducts discharging explosive or flammable vapors, fumes or dusts to the outdoors shall be located with _______ from property lines
Cleanouts serving horizontal sections of grease ducts shall be located not more than _____ from changes in direction that are greater than 45 degrees
The cross-sectional area of a flue serving a solid-fuel-burning appliance shall be not greater than ______ times the cross-sectional area of the appliance flue collar or flue outlet
For stationary small motors rated less than _______, the branch circuit over current device may serve as a controller.
Chimney and vent connectors shall have a minimum clearance of _______ to electric and oil incinerators
The _____ is the current drawn by the motor just as it begins to start but before the rotor begins to rotate
Ozone cabinets and ozone gas-generator rooms for systems having a maximum ozone generating capacity of 1/2 pound (0.23 kg) or more over a 24-hour period shall be mechanically ventilated at a rate of not less than ______ air changes per hour:
If the replacement compressor motor draws 35 amperes current, what is the minimum rating for disconnecting means used to protect the motor?
The conductors sized 1/0 AWG or smaller shall be permitted to be run in parallel for frequencies higher than _______ HZ.
Make up air duct insulation installed within _____ of a Type I commercial kitchen hood shall be noncombustible
Thermocouple converts _____ energy to ______ energy
For determining all welded and brazed joints are liquid tight, a light test shall be performed by passing a lamp having a power rating not less than _____ through the entire section of duct work to be tested.
The light solid lines on an installation diagram shows the low voltage ______ winding
Capacitor motor has:
Which of the following locations would most likely require installation of a ground fault circuit interrupter?
Insulation resistance is measured using ___
Gasket and sealing materials for duct to exhaust fan connections shall be rated for continuous duty at a temperature of not less than ______
The termination point of all environmental air exhaust outlets and ducts discharging to the outdoors shall be located _____ from property lines:
Frequency in a dc circuit will be ______
Power factor is ______ of the angle between voltage and current wave
Which of the following has negative charge
The effective value of an AC sine wave is equal to the _______ times the maximum value
The individual modular boiler shall be limited to a maximum input rating of ______ Btulh gas
Which of the following is a self-starting motor
In residential buildings, small appliance loads should have two or more _______.
Service factor of the typical motor will be ______
The foam plastic insulation shall be covered by corrosion-resistant steel having a base metal thickness of not less than _____
1 watt power = _______ Btu
The maximum horizontal length of a single-wall connector shall be _______ of the height of the chimney or vent.