ADT490 TroubleShooting Introduction to Troubleshooting

2 Definition of “Trouble” 2 Trouble a condition in which the fire alarm system is operating in a degraded mode.

3 Trouble 3

4 Why is Troubleshooting so important? 4 Troubles/problem that can worsen over time. Examples: single ground fault turns into a double ground Impact on Signal circuit power failure

5 Why is Troubleshooting so important? 5 Central Station/Signal Receiving Operator’s view minor or complete failure Investigation of a Problem urgent for life safety.

6 Relevant Codes & Standards 6 What code or standard reflects the necessity for troubleshooting? The Fire Code clearly states “building owner responsible maintaining fire alarm system functionallity as “the failure or malfunctioning of the appliance, device or component would adversely affect fire or life safety”.

7 Where Can Troubles Occur 7 1)Power supply 2)Input circuits 3)Output Circuits

8 Where Can Troubles Occur 8 4)Device failure A Beam Detector fully blocked will also cause a trouble signal. A mis-addressed detector gives Trouble and “Unconfigured device” 5)Intentional (Disable or Bypass).

9 What can the customer tell us? 9 Owner, superintendent, or custodian.

10 What can the customer tell us? 10 Clues o “ This always happens a couple of days after it rains”. o “ The phone company was in a while ago or cable guys were working on the 4 th floor.” o “ The pool area has always been a problem

11 What can the customer tell us? 11 Ask questions: o Have there been any contractors working in the building in the past week or two? what exactly were they doing and where in the building were they working in? o When did the trouble condition (or false alarm) occur? o Have there been any complaints of leaks of any kind?

12 Circuit Integrity Review 12 Any circuit features the Fire Alarm System needs: 1.Metallic continuity 2.No grounds 3.No wire-to-wire shorts

13 Circuit Integrity Review 13 Conventional-style Fire Alarm System, small current through the circuit the circuit opens and the current stops. interruption of current detected displayed as a Trouble condition.

14 Circuit Integrity Review 14 Addressable-style Fire Alarm System, digital communication between FACP and devices stops. lack of response detected by the FACP displays a trouble condition and lists the missing device(s)

15 Circuit Integrity Review 15 Often not obvious disconnected or break. Often connection to a device where the open or break occurs. May be from improper stripping - nick or twisted too tightly under a wire nut (Marrette®).

16 Circuit Integrity Review 16 Over-tightening screw can result in fracturing May be some time later. “opens” may be intermittent - repeated troubles.

17 Circuit Integrity Review 17 Circuits must be free of grounds - both circuit conductors. Circuits will tolerate a single ground still operable second ground on the other conductor entire circuit will fail - shorted together By common ground path ie steel junction box or EMT conduit. FACP’s detect current increase to ground with a ground-sensing circuit in the power supply.

18 Circuit Integrity Review 18 In a conventional panel a ground condition displayed as “System Trouble” Recent panels a yellow LED ie “Ground” or “Earth” also lit. Zone Trouble LED will not be lit – impact on current small A ground, unlike an open, is not shown as a Zone trouble. Same for a single ground on signal circuit.

19 Circuit Integrity Review 19 A wire-to-wire short most dangerous of circuit troubles. resistance is zero & voltage disappears. In a signal circuit a short renders the entire circuit inoperable In an addressable input / output circuit short -> all communication STOPS system “crash”.

20 Circuit Integrity Review 20 Only on a conventional Initiating circuit (and Sprinkler Supervisory circuit) short same as manual stations, heat detectors etc circuit current will increase FACP sees this as an alarm condition.

21 Circuit Integrity Review 21 Wire-to-wire shorts are usually from poor installation practices stretching wire at conduit bends -> damage insulation burr cuts through insulation and provide a short between two conductors wire-to-wire short same as a double ground condition.

22 Faults to Trouble 22 1)Open circuit – either on an input circuit or output circuit, an open -> break in a conductor or disconnection from a device. In a conventional system -> loss of supervisory current FACP and a trouble display (visual and audible) is created. In addressable system devices on a Data Communication Link (DCL) beyond a break reported as missing with visual and audible Trouble indication.

23 Faults to Trouble 23 2)Shorted circuit –> unable to support any voltage Circuit current will increase. Causes alarm if circuit conventional initiating. conventional signal -> inoperable. In an addressable system DCL communication with the panel STOP.

24 Faults to Trouble 24 3)Ground – Devices on conventional circuits and addressable DCL circuits Required to work over a single ground condition. Double ground same as a short from to poor installation or water leaking into a device. `FACP voltage on circuits “floats” above ground creating a voltage between both “+ve” and “–ve” to earth allows ground detection on both sides of the circuit.

25 How do we know a system is in Trouble? 25 1)Audibly – a FACP trouble buzzer manually silence-able by pressing “Panel Silence”,or “Trouble Silence” etc. Note: Buzzer also used with sprinkler supervisory switch accompanied Supervisory LED

26 How do we know a system is in Trouble? 26 2)Visually – System Trouble or Common Trouble LED lit. Look for another LED on. Typically, only the green “AC On” LED should be lit. Other LEDs may be hidden behind the front panel. Some pulsing amber LEDs may be normal (i.e. communication)

27 How do we know a system is in Trouble? 27 3)Remote from Signal Receiving Centre or a call from the building owner or property manager.

28 What tools will we use in Troubleshooting routines? 28 1)Eyes and Ears – Human Detection Look for flashing LEDs on smoke detectors and Fault Isolators. Determine if some devices still operate on Trouble.circuit Carefully note What indicators are on when you look at the FACP. Look for messages on the Liquid Crystal Display (LCD).

29 What tools will we use in Troubleshooting routines? 29 2)Logic What happened immediately prior to the Trouble condition? What contractors have been in the building? Recent weather? i.e. rain, likely place for a wet ground? Identify circuit in trouble with resistor substitution. Boolean approach divides circuit in half.

30 What tools will we use in Troubleshooting routines? 30 3)Analog or digital multi-meter read circuit current, voltage, resistance, and resistance to ground.

31 What can the FACP tell us? 31 Study the FACP. Determine if trouble is in one of 5 areas Input, Output, Power, Device trouble, Bypass. FACP give clue trouble is signal circuit or initiating circuit..

32 Exercise AC Battery System Alarm System Trouble Circuit Ground System Silenced Bypass Z1 Alarm Z1 Trouble Z2 Alarm Z2 Trouble Z3 Alarm Z3 Trouble Z4 Alarm Z4 Trouble [E] Smoke detector operated on Zone 2, no 115VAC for FACP, wire has broken on Zone 3, signals are operating. [A] Bells are ringing, a wiring break in Zone 3, Batteries are weak, MPS active in Zone 2 [B] Alarm on Zone 3, open on Zone 2, Emergency lights are on in FACP room [C] Pull station pulled on Zone 2, power failure, building is quiet, open on Zone 3 [D] FACP breaker has operated, horn is missing, open circuit and single ground on Zone 3

33 Exercise AC Battery System Alarm System Trouble Circuit Ground System Silenced Bypass Z1 Alarm Z1 Trouble Z2 Alarm Z2 Trouble Z3 Alarm Z3 Trouble Z4 Alarm Z4 Trouble E] Temporal pattern is heard throughout, zones 1-3 are disconnected from the FACP, OS&Y active on Zone 4 [A] Power has been interrupted to the FACP, A pull station is in alarm on Zone 4, An open-circuit trouble on Zone 3, building is quiet. [B] Double ground has on Zone 4, emergency power is not grounded, signals are operating, main electrical feed to FACP is good. [C] Building is quiet pull station has been operated on Zone 3 and a double ground has on Zone 4. [D] Zone 4 bypassed because it is grounded, the building is silent, emergency power is in open circuit trouble, the main power feed is disconnected

34 Exercise AC Battery System Alarm System Trouble Circuit Ground System Silenced Bypass Z1 Alarm Z1 Trouble Z2 Alarm Z2 Trouble Z3 Alarm Z3 Trouble Z4 Alarm Z4 Trouble [E] No choices describe the correct scenario. [A] All power to FACP has failed, Alarm on Zone 3, Open circuit on Zone 1, building is quiet. [B] Batteries are charging, signals have failed, Trouble on Zone 1, Alarm on Zone 3 [C] AC is on, battery fuse has failed, heat detector is disconnected on Zone 1, wire disconnected & grounded behind a bell. [D] Ground on Zone 3, open on battery connection, short on Zone 1, signals are operating.

35 Device Failure In conventional systems, An internal electrical failure of a device will not cause a Trouble condition, if integrity of the circuit is not affected. A break in the coil winding of a bell, disconnection of the blocking capacitor in a speaker, corrosion of a switch in a manual station, failure of a photo-receptor in a smoke detector Device inoperable yet not cause a trouble condition. Only caught during a regular, periodic inspection.

36 Device Failure Some devices can create a trouble signal on their own these are primarily addressable analog devices report individual condition like accumulated dirt or environmental changes. address not part of the programmed data base will make generating a Trouble condition, and displaying a message on the Liquid Crystal Display as “unconfigured device”.

37 Device Failure Beam Detector full blockage of the photo - receiver creating a Trouble warning that it has been rendered inoperable.

End of presentation