Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
35 Cards in this Set
- Front
- Back
|
What kind of smoke detectors are authorized for ship use? |
Underwriter Laboratory (UL) approved smoke detectors, which operate on a 9-volt battery and have a 30-day audible low-voltage alarm |
|
|
At minimum, one detector shall be mounted to the overhead of living and berthing spaces that have a capacity of _______ people |
1 to 10 |
|
|
Spaces having a capacity of _________ people shall have no less than two detectors |
11 to 20 |
|
|
Spaces having a capacity of _________ people shall have no less than three detectors |
21 to 30 |
|
|
At minimum, how many smoke detectors must be located in each passageway that serves a living or berthing space? |
1 |
|
|
A rate-of-rise detector sounds an alarm when it senses a temperature increase exceeding _________ per minute |
8.3°C (15°F) |
|
|
Infrared detector alarms are activated when a flicker rate is between ________. |
8 Hz and 15 Hz |
|
|
What does the alarm circuit consist of? |
the alarm device and the alarm target relay, which contain open contacts. |
|
|
What does the supervisory resistor do? |
permits a limited amount of current to flow through the circuit when the alarm switch is open, thus keeping the relay coil energized
(If the relay coil de energizes, trouble indicactor goes off) |
|
|
What is the ohm rating of the supervisory resistor on an alarm circuit? Wattage? |
7,000 ohm, 5 watt |
|
|
On what circuit is the flooding alarm wired? |
FD |
|
|
What are flooding sensing units comprised of? |
a float-type, magnetically operated reed switch. |
|
|
On what circuit is the CO2 flooding alarm wired? |
FR |
|
|
What does the CO2 alarm system consists of? |
pressure-operated switches which are installed in each of the discharge lines of the primary and reserve banks of compressed CO2. |
|
|
What purpose do the CO2 pressure switches serve? (2) |
• To shut down the ventilating system. • To light red lamps within the FR (CO2 flooding alarm) circuit indication system and to sound an alarm bell. |
|
|
What two safety devices are CO2 suppression systems equipped with? |
- time delay mechanism
- audio and visual alarm showing that the system has been activated |
|
|
On what circuit is the high temperature alarm wired? |
F |
|
|
What does the high temperature alarm circuit use to detect temp? |
mercury-operated thermostats |
|
|
What three temperature settings do mercury-operated thermostats use? |
105F - magazines 125F - storerooms and paint lockers 150F - " |
|
|
On what circuit does the security alarm operate? |
FZ |
|
|
On what circuit does the air flow indicator and alarm operate on? |
HF |
|
|
What three units make of the air flow indicator and alarm system? |
- indicating and control panel - airflow sensor unit - airflow remote alarm unit |
|
|
What circuit does the wind direction indicator operate on? |
HD |
|
|
What circuit does the wind speed indicator system operate on? |
HE |
|
|
What is an anemometer? |
wind direction and speed indicator |
|
|
What is wind speed measured by? |
a three-bladed impeller fastened to the armature of a tachometer magneto, |
|
|
When the magneto shaft is rotated at 1,800 rpm, what should the voltage output be? |
9.20 ± 0.05 volts. |
|
|
Voltage output can be measured on the wind speed transmitter by multiplying rpm of the magneto by what? |
0.00511. |
|
|
What is an electrical device designed to give constant visual indication of wind speed and direction? |
wind speed/direction indicator |
|
|
What voltage/frequency does the indicator operate on? |
115 vac, 60 hz |
|
|
What is wind speed indication a result of? |
a DC signal generated by the wind speed magneto and transmitted to the DC voltmeter in the indicator. |
|
|
What is the wind direction indication a result of? |
the direction synchro supplying a signal to the synchro in the indicator. |
|
|
When using two indicators or an indicator and recorder, you must first _______ |
Remove the 2,300-ohm resistor from the indicators or indicator and recorder |
|
|
When using one indicator, __________ |
A 2,300-ohm resistor must be connected across the "+" and "-" terminals. |
|
|
What should the internal DC resistance of the wind speed voltmeter be? |
2,300 ohms plus or minus 0.5 percent. |
