MI Fire Alarm flashcards
MI Fire Alarm · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Zone (conventional system)
- A defined area of the protected premises; a conventional panel reports alarms by zone rather than by individual device, so the exact device is not annunciated.
- Addressable device
- A field device with a unique address that the control unit can identify individually for alarm, trouble, and supervisory annunciation.
- Supervisory signal
- A signal indicating an off-normal condition of a system or protected equipment, such as a closed valve or low air pressure, distinct from alarm and trouble.
- Trouble signal
- A signal indicating a fault in the fire alarm system itself, such as an open circuit, ground fault, or power failure.
- Class A circuit
- An initiating device or notification appliance circuit that continues to operate with a single open or ground fault because the circuit returns to the panel.
- Waterflow switch
- An initiating device on a sprinkler system that detects water flow and sends an alarm signal to the fire alarm control unit.
- NFPA 72
- The National Fire Alarm and Signaling Code, which governs the installation, testing, and maintenance of fire alarm systems in the United States.
- Smoke detector spacing
- For smooth, level ceilings, smoke detectors are generally spaced at 30 ft, covering up to 900 square feet per detector.
- Pull station height
- Manual fire alarm pull stations must be mounted between 42 in. and 48 in. above the finished floor, measured to the operating handle.
- Sleeping area audibility
- In sleeping areas, notification appliances must produce at least 75 dBA at the pillow, or 15 dBA above ambient, whichever is greater.
- Diffuser clearance
- Smoke detectors must be at least 3 ft from supply or return air diffusers to prevent air movement from diluting smoke and delaying detection.
- Ohm's law
- The relationship V = I × R, where V is voltage in volts, I is current in amperes, and R is resistance in ohms.
- Electrical power formula
- Power in watts equals voltage times current (P = V × I); it also equals I²R and V²/R for resistive circuits.
- Series circuit resistance
- In a series circuit, total resistance is the sum of the individual resistances, and the same current flows through every component.
- Parallel circuit resistance
- In a parallel circuit, the reciprocal of total resistance equals the sum of the reciprocals of the branch resistances, and voltage is the same across branches.
- End-of-line resistor
- A resistor at the end of a supervised circuit that allows the panel to detect opens and shorts by monitoring circuit current.
- Ground fault
- An unintentional connection between a conductor and ground, detected by the panel's ground-fault monitoring and annunciated as a trouble condition.
- Battery standby calculation
- Standby capacity equals standby current times required hours plus alarm current times alarm duration, with a derating factor applied.
- Acceptance test
- A functional test of a newly installed fire alarm system, witnessed by the authority having jurisdiction, before the system is placed in service.
- Smoke detector annual test
- A yearly functional test using smoke or the manufacturer's listed method to verify the detector responds to smoke, not just its electronic circuit.
- Waterflow switch test
- A semiannual test performed by opening the inspector's test valve to verify the waterflow switch sends an alarm signal to the panel.
- Tamper switch test
- A semiannual test of the supervisory switch on a sprinkler control valve to verify it annunciates a supervisory signal when the valve is moved.
- Duct smoke detector
- A detector installed in an HVAC duct to sense smoke and initiate shutdown of air-handling equipment; it does not replace area smoke detection.
- Elevator recall
- A fire alarm function that, upon alarm, sends elevators to a designated landing and disables normal operation to protect occupants.
- Alarm silence function
- A control unit function that silences notification appliances without resetting the system; the alarm condition remains until reset.
- Signaling line circuit
- The supervised circuit over which an addressable panel communicates with field devices, monitored for opens, shorts, and grounds.
- Voltage drop
- The loss of voltage along a conductor, calculated as Vdrop = I × Rconductor, where resistance depends on wire gauge and length.
- Open circuit
- A break in the conductor path that stops current flow; on a supervised fire alarm circuit it is detected and annunciated as a trouble condition.
- Short circuit
- A low-resistance path that bypasses the normal load, causing excessive current; on a supervised circuit it is detected as a trouble condition.
- Authority having jurisdiction
- The organization or official responsible for approving fire alarm installations, witnessing acceptance tests, and enforcing the applicable code.
- As-built drawings
- Record drawings maintained and updated to reflect the installed fire alarm system, including device locations and circuit routing.
- Sensitivity testing
- A test verifying a smoke detector operates within its listed sensitivity range; detectors failing the test must be cleaned, recalibrated, or replaced.