joe tedesco
Senior Member
- Location
- Boston, Massachusetts
What parts of NFPA 72, and the NEC apply?
Fire Alarm Equipment Installations
- Thread starter joe tedesco
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lady sparks lover
Senior Member
Re: Fire Alarm Equipment Installations
Can you explain??Originally posted by joe tedesco:
What parts of NFPA 72, and the NEC apply?
joe tedesco
Senior Member
- Location
- Boston, Massachusetts
Re: Fire Alarm Equipment Installations
NFPA 72 covers Fire Alarm Systems, and Article 760 in the NEC covers the same.
Give me a summary of the electrical circuits here.
NFPA 72 covers Fire Alarm Systems, and Article 760 in the NEC covers the same.
Give me a summary of the electrical circuits here.
goldstar
Senior Member
- Location
- New Jersey
- Occupation
- Electrical Contractor
Re: Fire Alarm Equipment Installations
Joe,
It's been a while since I've worked on fire alarm systems so you're stirring up a lot of dust in my brain. I'm not sure what it is you're looking for but here goes :
NEC
760.3(D) Corrosive, damp or wet locations
760.1 Fire alarm circuit identification
760.42 Circuit marking
760.54 Installation of conductors
760.61(D) FPLP cable( if the wiring ran through a plenum ceiling before entering the sprinkler room) or (F) FPL cable (if not)
I misplaced my copy of NFPA 72 (1999) so hopefully some of the others can comment on that.
The only thing I would change in this photo (and it's a matter of personal preference and workmanship) is to substitute seal-tight for the greenfield whips used to the devices. Greenfield has a tendancy to rust rather quickly in these applications.
Joe,
It's been a while since I've worked on fire alarm systems so you're stirring up a lot of dust in my brain. I'm not sure what it is you're looking for but here goes :
NEC
760.3(D) Corrosive, damp or wet locations
760.1 Fire alarm circuit identification
760.42 Circuit marking
760.54 Installation of conductors
760.61(D) FPLP cable( if the wiring ran through a plenum ceiling before entering the sprinkler room) or (F) FPL cable (if not)
I misplaced my copy of NFPA 72 (1999) so hopefully some of the others can comment on that.
The only thing I would change in this photo (and it's a matter of personal preference and workmanship) is to substitute seal-tight for the greenfield whips used to the devices. Greenfield has a tendancy to rust rather quickly in these applications.
- Location
- Massachusetts
Re: Fire Alarm Equipment Installations
in this area there are few FDs that would except that argument.
I would be interested to know if any one has a good way to avoid supporting the box on a pipe nipple.
Many of these valves are double pole, double throw resulting in 12 leads for class A fire alarm wiring.
There is no space for splices inside the valves box, it comes with 12 leads about 6" long hanging out of a 1/2" NPT hole.
There you go with common sense again,
in this area there are few FDs that would except that argument.I would be interested to know if any one has a good way to avoid supporting the box on a pipe nipple.
Many of these valves are double pole, double throw resulting in 12 leads for class A fire alarm wiring.
There is no space for splices inside the valves box, it comes with 12 leads about 6" long hanging out of a 1/2" NPT hole.
G
Guest
Guest
Re: Fire Alarm Equipment Installations
Or, did I misunderstand the question
[ September 27, 2003, 01:23 PM: Message edited by: awwt ]
I kick a piece of right-angle perforated-strut from the J-box back to the wall. That holey stuff like the garage door opener people use to hang their garage door tracks or to hang the opener. Or, you can flatten the both ends of 1/2" EMT and kick a brace (or two) back to the wall. Tek screw the strut to the box, and red-head it or tap-con screw it to the concrete wall-- or lag, screw, or tek-screw it to the framing..
Or, did I misunderstand the question
[ September 27, 2003, 01:23 PM: Message edited by: awwt ]
- Location
- Massachusetts
Re: Fire Alarm Equipment Installations
I will admit I have never tried this as floating the box seems to be accepted trade practice.
In the picture above using J line looks easy, above a suspended ceiling with 5 to 10 feet up to a truss it could get tricky.
I am surprised that UL would not require a factory JBox on the valve.
[ September 27, 2003, 01:29 PM: Message edited by: iwire ]
No you did not, yes I guess we could use J line (right angle perf. metal) for this.Originally posted by awwt:
Or, did I misunderstand the question
I will admit I have never tried this as floating the box seems to be accepted trade practice.
In the picture above using J line looks easy, above a suspended ceiling with 5 to 10 feet up to a truss it could get tricky.
I am surprised that UL would not require a factory JBox on the valve.
[ September 27, 2003, 01:29 PM: Message edited by: iwire ]
G
Guest
Guest
Re: Fire Alarm Equipment Installations
Buy two 10-foot lengths. Make a "V" to the truss with the point of the V at the box. What else can you do? As long as it's holey it will be blessed by the inspector.
../Wayne C.
[Edited to answer the next post from iWire below]:
U-Bolt would be cool if the AHJ will accept it. I was trying to keep it pure. Maybe build your jungle gym in the attic space and have it terminate at (or adjacent to) the T-Bar for the ceiling. Then run one or two short sections of J-Bar down to the handy box. In summary: Make a 3-point jungle gym where it can't be seen-- then a short hop to the handy box. Sometimes you have to silly rig things to meet the AHJ's interpretation of the code. Try to keep the silliest parts hidden from view from the GP.
[ September 27, 2003, 02:19 PM: Message edited by: awwt ]
Buy two 10-foot lengths. Make a "V" to the truss with the point of the V at the box. What else can you do? As long as it's holey it will be blessed by the inspector.
../Wayne C.
[Edited to answer the next post from iWire below]:
U-Bolt would be cool if the AHJ will accept it. I was trying to keep it pure. Maybe build your jungle gym in the attic space and have it terminate at (or adjacent to) the T-Bar for the ceiling. Then run one or two short sections of J-Bar down to the handy box. In summary: Make a 3-point jungle gym where it can't be seen-- then a short hop to the handy box. Sometimes you have to silly rig things to meet the AHJ's interpretation of the code. Try to keep the silliest parts hidden from view from the GP.
[ September 27, 2003, 02:19 PM: Message edited by: awwt ]
- Location
- Massachusetts
Re: Fire Alarm Equipment Installations
I can build a lot of things but it also has to look professional.
I can not be building jungle gyms for each handy box.
Maybe J Line back to a U-bolt around the pipe, we are already using the pipe for support of the flow switch in the picture, another common practice.
I can build a lot of things but it also has to look professional.
I can not be building jungle gyms for each handy box.
Maybe J Line back to a U-bolt around the pipe, we are already using the pipe for support of the flow switch in the picture, another common practice.
Re: Fire Alarm Equipment Installations
Hi, i am in NJ, amd our inspectors have tampers on all valves and that there be a valve before and after the flow valve. The chain or bar method thru the shut off valve is not being allowed here anymore. Any else seeing anything similar in other states.
Rob
Hi, i am in NJ, amd our inspectors have tampers on all valves and that there be a valve before and after the flow valve. The chain or bar method thru the shut off valve is not being allowed here anymore. Any else seeing anything similar in other states.
Rob
goldstar
Senior Member
- Location
- New Jersey
- Occupation
- Electrical Contractor
Re: Fire Alarm Equipment Installations
The photo shows the valve being chained closed which is the first level of security. If that chain is cut and the valve is manually closed it will send a supervisory ?off normal? signal to the fire alarm system indicating a fault. However, aside from proper support of the handy box, installing a handy box or LB-LR under this switch leaves the possibility for a saboteur to defeat its purpose by leaving the circuit terminations exposed. Manufacturers should make this switch so that terminations can be made inside the enclosure. That way an installer can run seal-tight directly to the device without any breaks. Just my opinion.
I believe the onus for the proper installation of this type valve tamper switch lies (for the most part) with the manufacturer. If I remember this switch correctly there are 3 sets of switches (2 SPDT and 1 N/O) internally factory pre-wired with a short cable harness leaving through a threaded hub. Now, the proper terminology for this switch is a ?valve tamper (or supervisory) switch? with the key word being TAMPER . Having the need to make circuit connections in an external (in this case ? handy) box defeats the purpose.
The photo shows the valve being chained closed which is the first level of security. If that chain is cut and the valve is manually closed it will send a supervisory ?off normal? signal to the fire alarm system indicating a fault. However, aside from proper support of the handy box, installing a handy box or LB-LR under this switch leaves the possibility for a saboteur to defeat its purpose by leaving the circuit terminations exposed. Manufacturers should make this switch so that terminations can be made inside the enclosure. That way an installer can run seal-tight directly to the device without any breaks. Just my opinion.
websparky
Senior Member
- Location
- Cleveland, Ohio
Re: Fire Alarm Equipment Installations
goldstar,
One thing to remember about fire alarm wiring is that it is a monitored circuit. If someone would open the box and disconnect the wires, it would send a trouble signal to the panel. The panel can not be reset without solving the trouble signal first.
goldstar,
One thing to remember about fire alarm wiring is that it is a monitored circuit. If someone would open the box and disconnect the wires, it would send a trouble signal to the panel. The panel can not be reset without solving the trouble signal first.
websparky
Senior Member
- Location
- Cleveland, Ohio
Re: Fire Alarm Equipment Installations
Hi Guys,
I'm wondering why the AHJ's are not allowing a chain or other device to prevent the closure of these valves. Can anyone shed some light on this?
Thanks!
Hi Guys,
I'm wondering why the AHJ's are not allowing a chain or other device to prevent the closure of these valves. Can anyone shed some light on this?
Thanks!
big john
Senior Member
- Location
- Portland, ME
Re: Fire Alarm Equipment Installations
My ignorance again:
What exactly is the issue concerning support of that device box?
Is it simply that if it's hit, it could pivot on the chase nipple? If that's the case, and assuming that tamper switch has KO's all along the bottom, would it be acceptable to hold the device box to the tamper switch with two chase nipples so it couldn't pivot?
Or is the issue the fact that the tamper switch is supporting the box in the first place...?
-John
My ignorance again:
What exactly is the issue concerning support of that device box?
Is it simply that if it's hit, it could pivot on the chase nipple? If that's the case, and assuming that tamper switch has KO's all along the bottom, would it be acceptable to hold the device box to the tamper switch with two chase nipples so it couldn't pivot?
Or is the issue the fact that the tamper switch is supporting the box in the first place...?
-John
- Location
- Massachusetts
Re: Fire Alarm Equipment Installations
As I said earlier this seems to be an accepted trade practice in this area, but I believe an inspector could easily fail this installation with this code article.
- Location
- Massachusetts
Re: Fire Alarm Equipment Installations
Websparky,
Fire Dept's are another story, what is required in one town is prohibited in the next one over. :roll:
Some have one alarm and no troubles to the FD, another one has 12 alarms, trouble and supervisor to the FD by way of a radio master box.
Some have 2 sprinkler zones another the FD wants 7 sprinkler zones.
I wired a set of tamper switches to monitor modules that where programed to trip the supervisory contacts at the panel, I got reamed, the FD made me rewire them the old way so that operation of the switch would open the loop and put the panel in trouble.
In a town that only allows 3 types of panels we chose an addressable panel that they do accept but at the final walk through they told us they do not accept the pull stations from that manufacturer. The reason was Dual Action as opposed to Double Action. ??????
We tried to fight this and would have had to go to court to win.
We had to buy non addressable pull stations and use monitor modules, I literal ripped the modules off of the pulls we had bought and used them on the new pull stations. This they where happy with. UL ? :roll:
And the best one ever, The FD made me solder the end of line resistors onto the conductors the reason "They fall off and cause false troubles"
I will stop ranting now.
As to original question if the FD sees the valve can be wired they will expect it to be wired chain or not.
Websparky,
Prepare for rant
Fire Dept's are another story, what is required in one town is prohibited in the next one over. :roll:
Some have one alarm and no troubles to the FD, another one has 12 alarms, trouble and supervisor to the FD by way of a radio master box.
Some have 2 sprinkler zones another the FD wants 7 sprinkler zones.
I wired a set of tamper switches to monitor modules that where programed to trip the supervisory contacts at the panel, I got reamed, the FD made me rewire them the old way so that operation of the switch would open the loop and put the panel in trouble.
In a town that only allows 3 types of panels we chose an addressable panel that they do accept but at the final walk through they told us they do not accept the pull stations from that manufacturer. The reason was Dual Action as opposed to Double Action. ??????
We tried to fight this and would have had to go to court to win.
We had to buy non addressable pull stations and use monitor modules, I literal ripped the modules off of the pulls we had bought and used them on the new pull stations. This they where happy with. UL ? :roll:
And the best one ever, The FD made me solder the end of line resistors onto the conductors
the reason "They fall off and cause false troubles" I will stop ranting now.
As to original question if the FD sees the valve can be wired they will expect it to be wired chain or not.
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