Resistors/PID/Networking Flashcards
A linear resistor’s resistance remains constant when variable voltage is applied.
a. True
b. False
a
A variable resistor’s resistance:
a. Is non-adjustable
b. Is adjustable
c. Changes with temperature
b
A non-linear resistor is not affected by temperature and light.
a. True
b. False
b
What is a potentiometer?
3 terminal resistor that forms voltage divider
What is a thermistor sensitive to?
Temperature
A Negative Temperature Coefficient (NTC) thermistor’s resistance _____ when subjected to an
increase in temperature
decreases
A Positive Temperature Coefficient (PTC) thermistor’s resistance _____ when subjected to an
increase in temperature
increases
What type of thermistor is most commonly used as a temperature sensor
NTC
What is the purpose of a trimmer potentiometer?
calibrate/fine tune circuits
What kind of circuits can a trimmer be used to adjust?
air temp
set-points
2-10v dc
What is the purpose of a thermostat heat anticipator
adds internal heat to trick thermostat
Is the heat anticipator of a thermostat is wired in series or parallel with the burner control
circuit?
series
What should the thermostat’s heat anticipator be set to?
amount of current the control circuit is generating
What type of feedback does a proportional control use
linear
What does PID stand for in a proportioning control system
proportional, integral, derivative
What type of power source is used in a 4-20 mA proportional system
direct current
In a 0-10 VDC system it is necessary to use shielded twisted pair cable. true or false
true
What type of protocol does a Modbus system use?
master/slave
What type of system can Modbus be found in?
Burner management system (BMS)
Building Automation and Control Systems (BACS)
Boiler/hydronic control systems
all of the above
all of the above
What is BACnet?
a communication protocol for building automation
What can BACnet control? (3)
HVAC
lighting
buiding emergency controls
BACnet protocol makes it possible to integrate products from different manufacturers into one
project.
a. True
b. False
true
An application that LON can control is street lighting.
a. True
b. False
a
What does WiFi stand for?
wireless fidelity
WiFi uses wires to send signals between devices.
a. True
b. False
false
What frequency ranges does WiFi use?
2.4-5ghz
Bluetooth can be used for Connection of motion controllers to a PC when using VR headset. true or false
true
A communications satellite creates a communication channel between a source transmitter and
a receiver at different locations on Earth. True or False?
True
What can a communications satellite be used for?
Television
Radio
Internet
all of the above
all of the above
What is an alternative system for internet when a broadband system isn’t available in a remote
location?
A satellite system
What is a cellular network?
a. A communication network where the last link is wired
b. When jail cells are connected in series
c. A landline phone system
d. A communication network where the last link is wireless
d
What is a “cell” in a cellular network?
a. A fixed-location transceiver
b. A variable-location transceiver
c. A communication extended listening locator
d. A geosynchronous orbit communication satellite
a
