TPC 210 Flashcards
When preparing an elementary diagram, all lines must be:
Numbered consecutively
Dimming high pressure sodium HID lamps can cause:
Color shift
When you test a three phase, delta connected winding with a compass, the compass will indicate alternating North and south polee when the pole phase groups are:
Connected properly
On a rewound three phase motor, occasionally an entire pole phase group may be accidentally reversed. This results in overheating and an increase in the:
Magnetic hum of the machine
In autotransformer input circuits, each input line should be:
Fused
A helpful piece of information to have when revising a control circuit is the _____ wire or relay number. This information keeps you from having to hunt through the schematic.
Last
The ____ circuit of an electrical schematic is the simplest part of the diagram and the easiest to follow.
Power
Planned lighting maintenance primarily consists of _____ to economize on labor, ____ to optimize light levels and space appearance and ____ to correct abnormalities in operation.
Group re-lamping; fixture cleaning; troubleshooting
Interchanging any two supply leads of a three phase motor:
Reverses the direction that the motor runs
If you see underlined numbers 6 and 12 at the end of a rung containing CR8, this indicates that there are _____ on lines 6 and 12.
N.C. CR8 contacts
A gaseous discharge lamp, such as a florescent or HID, requires a _____ to provide proper starting voltage and regulate current.
Ballast
When trouble shooting combination starters, the number one symptom of a problem is the operator saying, “The motor _____.”
Doesn’t run
A relay that has “dogs” located directly above the operating bar is called a:
Latching relay
The systematic testing of all controls in a building to ensure that they perform and interact properly is known as:
Commissioning
On a blueprint, wall outlets are indicated by a circle with a:
Short line drawn to it
Over voltage, excessive current and frequent operation are possible causes of:
Burned or short circuited magnet coils
Worn or damaged ball and roller bearings are easily detected by the:
Unusual noise they produce
Memory can be built into either a pneumatic or electric control circuit containing only monostable devices by using:
Feedback
On a reversing starter, mechanical interlocks are used to prevent both sets of three phase contacts from being operated at the same time. The closing of ______ operates a mechanism that prevents the closing of the opposite contactor.
One contactor
