4 - Introduction to Fire Alarm Systems
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- Опубліковано 4 жов 2024
- I'm explaining how fire alarm systems work for new technicians or other employees who deal with these systems. This is my 4th video in a string of many Khan Academy-styled lessons. This video reviews the principle of NAC circuits using diodes and reverse polarity to trigger their A/V devices. It also introduces relays, or more specifically, alarm contacts on a fire alarm panel.
I'm really digging your videos. I wish other technicians could explain this in the field, seeing that I'm new at this. I've learned more in the last hour watching your videos than I have in the last year working with egotistical technicians.
Always learn so much from this guy, thank you sir
I'm a Health Inspector that oversees compliance with NFPA codes for medical facilities and this is AWESOME training for detailed behind the scenes knowledge of how these system "technically" work beyond the code requirements. Thank you for your time !!
Im currently a HS student interested to going to college and picking a course to help me in my pursuit of a fire and life protection career and i really like these videos, very interesting and may be extremely helpful in the long run
Excellent videos for rookies in the fire alarm field like me!
Thank you very much for your effort. We have learned so many things from your channel.
You're the best. Thank you so much for these videos.
doing a great service to the community, keep it up... YOU ROCK....
you rock
this are very simple explanations , like fire alarm for dummies.
I love it.
Great video again. Not sure how anyone can give this a thumbs down unless they want this information kept secret. Mike
IM in the IBEW Local 26 I have about 6 months under my belt with Fire Alarm Installation. These videos are great. Right now IM installing a class B style with SLC. NAC and IDC the SLC are addresseble. Learning how to run the wire with out any splices is one of the hardest things. And relays and contacts.
are there any visual resources to learn how to pull the wire correctly? so that youre not splicing
Not that I'm aware of. If it's SLC style B, there's no reason not to splice. People will argue that point, but there are cases where you'll make the circuit so much longer than it needs to be if you don't uses splices. Splices can be neatly done in terminal blocks inside Hoffmann boxes, or even neatly done with wire nuts. Again, you'll find people who will say I'm a hack for thinking that way, but they can't give you a reason to support their point. Obviously AV circuits and class A circuits are different.
@@JoeKlochanresponse from 1 year ago so sorry haha. I ran installed fire alarm for a school in which it was impossible not to have splices, we used space age terminal splice boxes. Facp was in a room in between a 20 foot tall cafeteria and different areas of the school branched out from there. Strange school layout so impossible not to do splices there. Very few problems came from that mainly just your normal ground fault here or a few wires not terminated properly. To cut down on loose wire problems I'd recommend wagos or terminal splice boxes wherever possible. Those boxes have test slots so you can meter it without removing the wire. Wire nut splices won't let you test unless you remove it.
I am a visual learner these video;s are extremely helpful
Great lecture. Thanks man
Thank you very much. You are great instructor🙏
I really like your videos really good explanations and everytime I look at them I learn something new. keep the good work!. and the same as the other comment I`ve learn more in this few minutes than the last year as and apprentice in my current job.
wow just stumbled on to these videos by accident. what a find keep up the great work.i have subscribed
u awesome, I like the way u explained with it
I enjoyed like U've enjoyed explaining this course
Thanks man your all video help a lot ...keep it up
Great videos from an industrial electrician. But FYI there is no neutral running down the power pole. They create it at the transformer on the pole. But really this videos rock.
The neutral is connected to the transformer but it is the messenger wire carrying the two energized conductors down to the house. The purpose of the neutral is to return the unbalanced current back to the source of electricity.
Why did you stop making videos, those SLC videos would be fantastic. Teaching only makes you better.
I have been in the industry for 20 years and one of my duties is to train our technicians. Some of which have been doing this for as long as I have some are not to knowledgeable of how to diagnose system troubles. I can't always be available to walk them through troubleshooting. With this all said I would ask two questions. First would be may i use your videos in my training. TBH so far you would take the same steps i would and giving examples and visuals will help several different types of learners. Plus i don't know how long it would take me to recreate something like this. the second would be which videos would you suggest to start these guys off. Most of them inspectors with some system knowledge but very little troubleshooting knowledge. Some have some troubleshooting knowledge but could use a refresher.
Yeah, of course you can use the videos. They're free on UA-cam for that reason. As far as where to start, it's hard to say. When I started making the videos I wasn't sure what they would turn into, or if anyone would ever see them. So I started in a place that made sense to me at the time for the people I was trying to train. If I were doing it over, I'd probably go in a different order. But I would start them off with video 1 and go in order, with the understanding that some videos may not be as relevant as others. I don't think this is the best format for everyone to learn, but some people seem to get some benefit from it.
Thanks!
thanks for all efforts you exert. I want to know about the EST (SIGA_CC1) module function and wiring. Thanks in advance.
Is that really how the door holder circuit is run? Is is run on the NAC circuit or Initiating device circuit, I need clarification??
Is it misleading that the white wire for neutral and red/grey for the split phase is shown on the power lines before the transformer? If this is a single phase split-phase system with the transformer centre-tapped on the secondary, wouldn’t the neutral be created at the transformer and the 3 wires on the lines be 3 phases? Also another wire grounding the transformer and a bond screw in panel.
10:20 >> alarm relay should be as trouble relay drawing when you explain the door function
I love his vedio! He is very fast talking though.
Can you do more on addressable systems
i have an a question the door held open when the circiut is completed you said. it shpould be opposite i think, baceuse there is energy on the magnet can you explain to me how it happend maybe i didt understand clearly. thanks in advance
Also if you could tell if each ZONE has its corresponding NAC otherwise how will FACP know which NAC to be activated? For example the Mech Room (Zone 2) you had shown in this video.
But what if someone just takes the wire out of the alarm but there is still connection to the EOLR?
Thank you!!!!
Good explanation but there is no ground on the light bulb base. The screw base is connected to the neutral.
Sorry if it is a stupid question, but can you kindly explain how the horn circuitry or NAC gets activated once alarm goes ON? Is there internal circuitry between zones and NAC? Or is it that since the FACP will carry a current during activation of alarm that the NAC also gets activated?
How is the whole process of getting a job in fire & burglar alarms? Do you have to know someone that knows someone to get in? Do companies give you a practical test before even considering you?
I have a two year degree in electronics and computers. Currently in Chicago.
+PBRshots I know this is old but you should be able to get hired. There are plenty of companies in Chicago. Apply to all of them and write a decent cover letter. If you still need help contact me directly.
Joe Klochan Alright thanks, I've sent you a private message.
thanks
@Joe Klochan- Sir, can you also explain the situation where the door is controlled by alarm circuit. You have mentioned that the door will remain open until the alarm activates. But practically, shouldn't the door be opened after alarm goes 'ON' for students to exit ?
That door isn’t an emergency exit door as you assume. It’s just an example. It could be a door leading someone farther from an emergency exit. Closing it helps direct traffic out of the building. Who knows so many scenarios
It depends what the is for incase of smoke control some doors will close on fire alarm.
Exit door will automatically release if they are magnetically held .It depends on how the whole building was designed by the fire engineers.
What reverses the polarity on the diode?
so the alarm system should still be functional even though there is a trouble alarm
must the resistors be connected at the end of the circuit? thanks for the video it helped though
Yes, otherwise the circuit beyond the resistor isn't supervised
@@JoeKlochan can you explain in brief about Est3 system , there is Siga-ab4g sounder base detector ,i want to know it needs 24 volt supply but from main control axulliary power or from booster power supply please clear it..
@@JoeKlochan sir i have little doubt on Nac circuit as u explained in video that current flows from negative to positive direction in this condition the Nac circuit cant activated because it requires reverse flows i mean from positive to negative direction then current gets block and shows open circuit and speakers get on ..am i right sir please explain
@@JoeKlochan normally when we test smoke detector or NAC circuit what happens it gets activated is there same thing happens that the polarity gets change from positive to negative & circuit get blocked and shows open and detector or sounder go to alarm
How is the door holder physically cabled? Is a cable run from the PSU to the fire panel, then from there to the door holder?
krankenshaft totally depends on the application. If it's a 120 volt door holder, it would all be in conduit. If it's 24 volt, you'd likely have a fire cable run from the door holder power supply to the relay, then to the door holder. At the relay, the negative wire would be spliced together (not touching the relay at all) and the positive would be landed on the contacts.
@@JoeKlochan When you say " all would be in conduit" does that mean the the wire would just be a loop to the magnet on the door and continue to hit a nother device from there?
Great vids I take my test next month.
I don't understand how a nac circuit is able to monitor the eol if a diode is stopping the current flow when its in a reversed polarity or normal state??
John Wayne if it reads -24v it should still have a current? Not 100% just a thought
John Wayne it's important to understand that the diode blocks current from flowing through the device only. It does not (it cannot) block the current from flowing on in the circuit, and thus through the end of line and back to the panel.
Picture a strobe with two black wires (negative) and two red wires (positive) landed on the device (an "in" and "out" segment of the circuit). These wires are physically touching each other and so currently the will flow through them. The diode is internal to the strobe, and is preventing current from ENTERING and flowing THROUGH the device, until the polarity is reversed. But it will still flow beyond that device and through the EOL.
Joe, any ideas on how I can get hands on training to learn this? I know the certification website has online courses and 2 day seminars in select states, but nothing in my area.
+Justmytake Unfortunately, I don't have good suggestions. The only good way I know of is to be hired by a fire alarm company and get hands-on experience. From there, the training is what you make of it. Although this isn't ideal, there's also some merit to it. There have been situations where I have been more interested in training people than they have been in learning. When people are somewhat thrown into the fire, the cream seems to rise to the top
uhhh theres no neutral bar it should be the red line which represent the " Hot Wire "and the " Neutral "wich is the white wire in replace of the black wire when your dealing with Line to Neutral circuit
There's no neutral bar in a breaker box? I'm not sure what you're saying.
Panelboard you mean. I get your idea of LINE - NEUTRAL system plus ground. But speaking of neutral bar theres no neutral bar seperated it should be Terminal 1 for "Line"and Terminal 2 for "Neutral"theres no seperated neutral bar... There's Gound Bar but no neutral bar seperated as you describe
@@JaysCoquilla that's definitely not true. Are you in a another country maybe? Every breaker box has a neutral bar. Also, I've never heard anyone call it a panel board, but you seem to be the authority on all things electrical...
awhh yeah heheh I'm a Filipino an Engineering student and A Registered Master Electrician. Hmmm I think some terminology is different but i think the Idea is the same Here on Your drawing we call it panel board inside theres multiple circuit breakers. we dont have neutral bar here. I think thats the Difference hence we have 220 L-L voltage and L-G but in america 110 only? I Guess?
@@JaysCoquilla bingo
THANKS very very very MUCH
All your videos are very simple and helpful 👌
Subscribe for sure 👍
What drawing soft where is that
It's just Microsoft paint, the software that comes standard on any computer. I just fill the background black.
Please explain in Telugu
Informative but a little wordy. Too many regressions. Speak in a straight line.