RST Study Flashcards
What is the total resistance of a circuit with two 25 ohm resistors in parallel?
12.5 Ohms
1 / ( 1/25 + 1/25 )
What is the standard High output voltage for a TTL circuit?
5 Volts
What does TTL stand for?
Transistor-Transistor Logic
What is capacitance measured in?
Farads
What is Inductance measured in?
Henries
What is Impedance measured in?
Ohms
In FORWARD Bias, a silicone diode will start conducting when what voltage is applied?
Approximately 0.7V
An increase of 3dB will amplify an audio signal ? times?
2
The brushes on a DC motor contact the ?
Commutator
When an instrument receives a small change in input, but registers no change in output, this type of error is called ?
Deadband
A 3-phase xfmr has a delta primary and wye connected secondary. If the secondary voltage is 480V phase to phase, what is it phase to neutral?
277V
A 3-phase xfmr has a delta primary and wye connected secondary. If the secondary voltage is 208V phase to phase, what is it phase to neutral?
120V
What is the Peak to Peak voltage of 120V RMS?
Approximately 340V
How much does a capacitor charge after one time constant?
Approximately 63.2%
What is the primary use of a Zener Diode in reverse bias?
Voltage Regulation
What is the difference between a contactor and motor starter?
A motor starter has overloads
What does DOE stand for? (In reference to timers)
Delay On Energize
What do overloads primarily protect against?
Overheating from excessive current
DRAM stores data on ?
Capacitors
What is the equation for gain?
Gain = output/input
A “megger” measures ?
Resistance
What are the three types of PLC counters?
Up, Down, Up-Down
How many leads on a BJT?
3 (Collector, Base, Emitter)
What does BJT stand for?
Bipolar Junction Transistor
What are the 3 ways instrumentation valves are controlled?
Electronic (most common)
Hydraulic
Pneumatic
What is the range of audible frequency?
About 20 Hz to 20 kHz
Which side of a diode is generally marked by a silver band?
Cathode
What two factors determine a motor’s RPM?
Frequency and the number of poles.
RPM = (Hz602)/ #of poles
What is the forward bias voltage of a Germanium diode?
0.3V
In hydraulic servo valves, DITHER is used to improve ?
Response Time
What are D-Flip Flops used for?
Data latching
In a diode, Current flows from ? to ?
Cathode to Anode
? Type Semiconductors have an excess of electrons, while ? Type have a deficiency of electrons?
N-Type - excess of electrons
P-Type - Excess of “Holes”
A ? diode is generally used in high frequency operations.
Schottky
How many diodes are utilized in half-wave? full-wave? and bridge? rectifiers?
Half-wave - 1
Full-wave - 2
Bridge - 4
A ? is a resistor that changes its resistance when the temperature changes.
Thermistor
What are the three basic parts of a VFD?
Converter (AC-DC) , DC Filter, Inverter (DC-AC)
The rate of capacitor charge/discharge is ?
Exponential
How many time constants does it take to charge a capacitor?
5
A class A amplifier is the ? effective and the ? efficient.
Most effective (100% signal)
Least efficient
A class C amplifier is the ? effective an the ? efficient
Least Effective
Most Efficient
A(n) ? is an instrument that provides a visual display of a waveform.
Oscilloscope
What are the three leads of a MOSFET?
Drain
Gate
Source
(Top to bottom, same order on schematic drawing)
What are the three leads of a Triac?
Anode 1 (MT1)
Gate
Anode 2 (MT2)
What are the color bands, in order, for a 4.7k ohm resistor?
Yellow, Violet, Red
What is the show lighting standard protocol?
DMX-512
What is a PID?
Proportional Integral Derivative Controller
What is the most common type of Integrated Circuit used today?
TTL and CMOS
A measurement device that transmits an analog signal has a typical range of ?
4 - 20mA
? is the basic function of all amplifiers
Gain
What does XIC stand for?
Examine If Closed
What does XIO stand for?
Examine If Open
What does DODE stand for?
Delay On De-Energize
What is an RTD sensor?
Resistance Temperature Detector
The best power transfer is when the impedance of the signal and the load are ?
Matched
In a Delta setup, phase CURRENT is multiplied by ? to get line current
The square root of 3
A graph showing continuous values over time is a(n) ? representation.
Analog
SRAM (Static RAM) refers to a ?
Flip-Flop
What are the two types of PLCs?
Fixed and Modular
Zener diodes are used in ? applications
voltage regulation
Triacs are ?-wave devices, while SCRs are ?-wave devices
Triac - Full Wave
SCR - Half Wave
In reference to motors, fuses protect the ? while overloads protect the ?
Fuses protect wire
Overloads protect motor
