Fire Dampers on NORMAL power??

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brother

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I was looking at the some circuits at a Hospital, and I discovered that the 'dampers' were on normal power. I know the dampers are not the same as the fire alarm itself, and I was told they were on a 'fail' safe system, so if the normal power went out then the dampers would close anyway.

I dont have much experience with fire dampers etc.. but I always was thought they had to be on emergency power/Life safety side NEC 517.32 2005. Am Im concern for nothing since its fail safe?? am I understanding how this is wired correctly??
 
These dampers are probably motorized to hold open, when power is cut, they close, thus "Fail Safe" if the breaker is turned off, wiring disconnected or broke then it will fail closed. If power is restored and the alarm relay contact is closed, then it will reopen again. If power is lost to the alarm relay or it goes into the alarm condition it closes also becoming a "Fail Safe" condition.
 
I forgot to mention that they have a spring return, so no power is needed to close. The motor just opens it up until it stalls out, does not hurt the motor, it is designed to do that.
 
Tell me about these motorized fire dampers. What triggers them to shut, normally?

I can't say that I've ever seen a motorized fire damper, and I make it a point to know about stuff like that. All the one's I seem to see are mechanical, fusible link type.
 
Brother.,

If the FA is tied to the dampers you should able find the " master damper " that useally found near the HVAC or trunk ( branch take off point ) line depending on the HVAC spec called for and I am pretty sure most Hosptail Mantanice dept do have a set of bleuprints on hand you can able see where it located as well.

And the other thing with non circital ventations they are designed to close the damper in case power failure mode ., Let me assumed { it may affect the answer } the HVAC unit operation will be reducded ( or limited operation ) during emegercy power mode

That one of few possbitly it can happend there.
And I know some FA is tied to the contractor or control panel in the HVAC so if the FA actavited it will shut the HVAC off automatically.

Merci,Marc
 
frenchelectrican said:
Brother.,

If the FA is tied to the dampers you should able find the " master damper " that useally found near the HVAC or trunk ( branch take off point ) line depending on the HVAC spec called for and I am pretty sure most Hosptail Mantanice dept do have a set of bleuprints on hand you can able see where it located as well.

And the other thing with non circital ventations they are designed to close the damper in case power failure mode ., Let me assumed { it may affect the answer } the HVAC unit operation will be reducded ( or limited operation ) during emegercy power mode

That one of few possbitly it can happend there.
And I know some FA is tied to the contractor or control panel in the HVAC so if the FA actavited it will shut the HVAC off automatically.

Merci,Marc
Click to expand...

So back to my original question, do you believe its a CODE VIOLATION?? Yes or No??
 
brother said:
So back to my original question, do you believe its a CODE VIOLATION?? Yes or No??
Click to expand...
Depending on how the HVAC is set up - NO IMO - odds are that the the HVAC units are not set up to RUN on the 'life safety' branches. They may be operated as a secondary to the 'critical' branch circuits from an optional stand-by power system or may be connected manually under some conditions. See the scopes laid out in 517.

As for servo vs. motor - call it what you like it has a motor in it.... But may make a great "Cat door".... My wife and I have wanted a way to keep the cat from cuddling up to the car as we exit the garage, and a damper actuator on a timer may be just the ticket to keep his butt out of harms way while we make a get-away..... Now I just have to keep an eye out during some demo to get one - pricey item.....
 
Assuming spring return (close) dampers and HVAC fans supplied by only 'normal' power what point would there be in supplying the dampers with E-Power?

But, it might make sense to check and see if the HVAC equipment related to those dampers is on Normal or E-power. I have done very little hospital work but recall working on the ATS at one that did in fact run the HVAC for the operating rooms.
 
I will agree that being on normal power since its fail safe system wouldnt 'affect' the function of the 'dampers' in particular, but just because it works right, doesnt meant it is CODE right. Ive read 517 and I just do not see where it is 'legal' to put the function of the dampers on normal power, when they need power because they are associated with the fire alarm systems.

If there is a code article exception specific im missing please quote it. Thank you.
 
Brother.,

Give me a day I will get ahold of one of my freind he work in Hosptail system alot so he may have a answer so bear with me.

For My option no it is not a code volitaton at all if done right and set up properly.

{ hopefully I will get the answer tonite otherwise in the moring due I am in France now }

Merci,Marc
 
iwire said:
If there is a code article requiring them to be powered closed please quote it. Thank you. :smile:
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There is no CODE requiring them to be powered closed that I know of nor did I say there was. What I am saying is that IF they are to be powered at all (OPEN or closed) that they are required to be powered by the emergency/life safety branch.

Fire dampers are associated/controled with the 'fire alarm', and the fire alarm is required to be powered by the emergency/life safety branch. NEC 2005 517.32 (C)(1) Fire alarms.
NEC 2005 517.32] No other function other than those listed in 517.32(A) through 517.32(G) shall be connected to the life safety branch. The life safety branch of the emergency system shall supply power for the following lighting, receptacles, and equipment
Click to expand...

Again I ask, If there is a code article exception specific Im missing please quote it. Thank you.
 
brother said:
So back to my original question, do you believe its a CODE VIOLATION?? Yes or No??
Click to expand...
No in answer to your question . I have done numerous systems of this type usually converted pneumatic systems to electrical and i can tell you from experience to get all of the microswitches working correctly and all at the same time is almost impossible. The duct guys usually supply thier own equipment with multi stacked contacts on open and closed status. The systems I have done only MONITORED these contacts and it was a small miracle when they all worked properly for the fire marshal on final. The problem is the mechanical and cheap microswitches employed in this scenario. They can all be easily wired right but few people understand this system and if you are going into some sort of maintenance for these systems get a lot of money because you will need it to troubleshoot these microswitches . The duct guy is going to blame you and you are going to blame him.These are usually just status lights as I said in hospitals.
 
iwire said:
If there is a code article requiring them to be powered closed please quote it. Thank you. :smile:
Click to expand...
Nothin' for ya Bob....

brother said:
Ive read 517 and I just do not see where it is 'legal' to put the function of the dampers on normal power, when they need power because they are associated with the fire alarm systems.

If there is a code article exception specific im missing please quote it. Thank you.
Click to expand...
You read ALL of it? - I'm not gonna type out the 05/8 for anyone....
From the 02: (Paraphased for topic relivence)
517.34 Equipment System Connection to Alternate Power Source.
The equipment system shall be installed and connected to the alternate power source such that the equipment described in 517.34(A) is automatically restored to operation at appropriate time-lag intervals following the energizing of the emergency system. Its arrangement shall also provide for the subsequent connection of equipment described in 517.34(B). [NFPA 99, 3.4.2.2.3(b)]
Exception: For essential electrical systems under 150 kVA, deletion of the time-lag intervals feature for delayed automatic connection to the equipment system shall be permitted.
(A) Equipment for Delayed Automatic Connection. The following equipment shall be arranged for delayed automatic connection to the alternate power source.
~~~~~~
(4) Smoke control and stair pressurization systems, or both.
(5) Kitchen hood supply or exhaust systems, or both, if required to operate during a fire in or under the hood.

~~~~~~

(B) Equipment for Delayed Automatic or Manual Connection. The following equipment shall be arranged for either delayed automatic or manual connection to the alternate power source:
(1) Heating equipment to provide heating for operating, delivery, labor, recovery, intensive care, coronary care, nurseries, infection/isolation rooms, emergency treatment spaces, and general patient rooms and pressure maintenance (jockey or make-up) pump(s) for water-based fire protection systems.
Exception: Heating of general patient rooms and infection/isolation rooms during disruption of the normal source shall not be required under any of the following conditions:
(a) The outside design temperature is higher than -6.7?C (20?F).
(b) The outside design temperature is lower than -6.7?C (20?F), and where a selected room(s) is provided for the needs of all confined patients, only such room(s) need be heated.
(c) The facility is served by a dual source of normal power.
~~~~~~~~~~
Click to expand...

Anyway - since brother wants a yes or no answer - he's not gonna get it - it's both yes and no depending on a number of factors. Manual connection could mean you wait for the power company to pull up a generator from a hundred miles away to get the HVAC back on IMO... Fire dampers closing with absence of power - on a non-life safety or critical branch is considered fail-safe, and does not affect the FA operation.
 
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