Module J8: Security Systems Worksheet

Question 1

What is a security system designed to do?

Answer 1

Protect property and people, and provide a feeling of security

Question 2

What are the five items that are normally a part of a security system design?

Answer 2

• Deterrence
• Prevention
• Detection
• Response
• Apprehension

Question 3

What is meant by the “onion-skin” approach?

Answer 3

Successive layers of protection throughout installation

Question 4

What three purposes does an alarm system serve?

Answer 4

• Deterrence
• Detection
• Response

Question 5

What are the three categories of protection (layers) using the onion-skin approach?

Answer 5

• Perimeter protection
• Space protection
• Spot protection

Question 6

What is provided by perimeter protection? What does perimeter protection refer too?

Answer 6

Provides early warning when intruder is still outside. Refers to devices to protect the outer perimeter of an installation

Question 7

What is space protection designed to do?

Answer 7

Designed to detect the presence of an intruder within a volumetric area

Question 8

What are the two advantages of space protection over perimeter protection?

Answer 8

Cost effective, less important to anticipate the point of entry

Question 9

What is the limitation of space protection?

Answer 9

• Does not provide early warning (intruder is already inside the premises)
• Does not allow customer to stay inside protected area

Question 10

What is spot detection designed to do?

Answer 10

Designed to protect a specific object or area

Question 11

Where is spot protection usually installed?

Answer 11

Around an item of value (cash, safes, paintings, etc)

Question 12

What are the three main circuits in a basic alarm system?

Answer 12

• Detection circuit
• Control circuit
• Output circuit

Question 13

What are the two states of operation for detection circuits?

Answer 13

• Secure (normal)

- Insecure (alarm)

Question 14

What is the most common output device used with a security alarm system?

Answer 14

Siren

Question 15

What are the two basic types of detection circuits?

Answer 15

• Closed loop

- Open loop

Question 16

What detection circuit is the most commonly used?

Answer 16

Closed loop

Question 17

What circuit provides better protection: a supervised or unsupervised circuit?

Answer 17

Supervised

Question 18

What are the four basic closed loop types?

Answer 18

• 2-wire
• 2-wire with end-of-line (EOL) resistor
• 4-wire
• 4-wire ULC

Question 19

Where are two-wire, closed loop circuits used?

Answer 19

Low security applications

Question 20

Where should the ELR be connected in a two-wire with end of line resistor loop?

Answer 20

At the end of the loop (last device)

Question 21

Do four-wire loop circuits provide a high or low security for window installations?

Answer 21

High

Question 22

What advantage does the ULC four-wire loop have over a two-wire loop?

Answer 22

Provides better protection against tampering

Question 23

Explain the basic operation of magnetic contacts for detection circuits

Answer 23

A magnetic switch is installed in a window or door, when magnet is placed next to it, it changes the state of the contact

Question 24

What are the four precautions considered when installing reed switches?

Answer 24

• They are fragile
• The have low current rating
• They must be aligned properly
• They must be kept away from metal in vicinity

Question 25

What is a PIR detector

Answer 25

Passive infrared radiation detector. Detects the presence of heat

Question 26

What is a passive detector?

Answer 26

It does not radiate any signal

Question 27

What is the component that is the heart of a passive infrared detector?

Answer 27

Pyroelectric element (PE)

Question 28

What is a detection pattern?

Answer 28

A pattern of infrared energy monitored by the detection device

Question 29

What are the five advantages of PIR detectors?

Answer 29

- Self-adjusting - Foolproof (to install) - Passive (do not emit radiation) - Extremely versatile - Detection fingers are adjustable

Question 30

What are the three disadvantages of PIR detectors?

Answer 30

- Normal differences in temperature can trip sensor - Unsupervised detection (can be blocked) - Range and sensitivity depends on ambient temperature

Question 31

What are two characteristics of microwave detectors?

Answer 31

- Emit microwave radiation (active device) | - Reacts to doppler shift (change in frequency)

Question 32

What are two advantages of microwave and ultrasonic detectors over PIR detectors?

Answer 32

- Sense motion toward the detector | - Unaffected be sources of heat

Question 33

What are three disadvantages of microwave detectors?

Answer 33

- Sensitive to fluorescent and neon lights - Inability to contain the detection pattern (microwaves pass through walls) - Water in pipes in the detection range can cause false alarms

Question 34

What is a Dual-Technology detector?

Answer 34

A type of detector that uses 2 different sensing methods to improve reliability

Question 35

What is the main advantage of a dual-technology detector?

Answer 35

Reliability and resistance to false alarms

Question 36

Describe the basic operation of the photoelectric beam detector

Answer 36

Beam of light is emitted from transmitter and directed at the receiver. If an intruder passes through and interrupts the beam, alarm is triggered

Question 37

What is an advantage of the photo-beam detector?

Answer 37

- Not affected by ambient conditions - Protects areas too hazardous for PIR - Good distance

Question 38

What is a disadvantage of the photo-beam detector?

Answer 38

- Expensive to install | - Takes much longer to setup/adjust

Question 39

What are the two main types of glass-break detectors?

Answer 39

- Audio detectors | - Shock sensors

Question 40

What is the principle of operation for an audio detector?

Answer 40

It listens to the sound of breaking glass. If the frequency of the break matches the profile of breaking glass, it triggers alarm

Question 41

What are the advantages of audio detectors?

Answer 41

Ability to protect large areas

Question 42

What are four causes of false alarms for audio detectors?

Answer 42

- High-pitched squeaks - Pet stores (animal noises) - Metal impact/scraping - High volume sounds - Kitchen noises (broken plates, etc)

Question 43

What are shock sensors? What is the basic principle of operation of a shock sensor?

Answer 43

A unit that can detect a shock wave made by intruder. Piezoelectric crystal acts as a microphone

Question 44

What is the common number of zones that come with intrusion alarm control panels?

Answer 44

4, 8, 16

Question 45

What are the three main status LEDs found on the control panel and give a brief description of their function

Answer 45

- Loop status LED - Ready status LED - Armed status LED

Question 46

What are three advanced features found in alarm panels/

Answer 46

- Zone bypass - System trouble - Alarm memory

Question 47

What is a monitoring station?

Answer 47

An offsite location to which alarm panels send communication in the alarm event

Question 48

What is an "exit delay"?

Answer 48

A feature that gives a user time to exit premises without the system going into alarm

Question 49

What is a "zone bypass"?

Answer 49

Ability of the security system to bypass (or disable) some of the zones

Question 50

A four-wire loop is also called a _________ or ________

Answer 50

double circuit, HI/LO loop

Question 51

In the secure condition on a four-wire loop, there is _______ ________ ________ between the two loops

Answer 51

no current flow

Question 52

The LO loop is called a ______ loop

Answer 52

24-hour

Question 53

Where is a four-wire loop system typically found?

Answer 53

In installations using window foil

Question 54

The contacts on detection devices for four-wire ULC closed loop circuits must be ___________

Answer 54

SPDT, with C, NO and NC terminals

Question 55

Most reed switches are able to conduct currents of only ______ or less

Answer 55

250mA