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Re: General fire discussions

Posted: Sat Jan 31, 2009 6:52 pm
by wasaint
BFB LT1 wrote:What about metro?
at least every 12mnths usualy done pre fire season helps make crews aware of the location of hydrants in there area and this way any hydrants that requier the water corp to fix it can be done before summer

Re: General fire discussions

Posted: Sat Jan 31, 2009 8:06 pm
by 4353
Quick question:

When a crew turns out a DBA it only seems to be for example perth 1st perth 2nd but if its a 000 call (structure fire) they send more. Just wondering any reason behind it ?

Reason i ask 000 call received for structure fire 7th floor Tower B in bentley im assuming its one off the homeswest buildings.

They sent kensignton, welshpool, canningvale,Perth CLP, straight up.

Re: General fire discussions

Posted: Sat Jan 31, 2009 8:11 pm
by yorky
General DBA's often aren't valid, and unless the place calls and confirms a fire there is no need to send anything more.

If there is a fire like the 7th floor one chances are there would be multiple calls to confirm, and that way they can gauge how many units to send ie lots ;)

Re: General fire discussions

Posted: Sat Jan 31, 2009 8:38 pm
by Mug
...That was funny...


Bassendean turned out to a DBA at Ascot quays apartments. 44 as usual.

But on the turnout message, the SO said "6ar Bassendean turning out DBA Ascot "kways" apartments." #-o

6ar's response was a bit more correct, but still wrong #-o .

Sometime later when belmont was turned out instead it became " kays".

Re: General fire discussions

Posted: Sat Jan 31, 2009 9:02 pm
by Toottoot
Mug wrote:...That was funny...


Bassendean turned out to a DBA at Ascot quays apartments. 44 as usual.

But on the turnout message, the SO said "6ar Bassendean turning out DBA Ascot "kways" apartments." #-o

6ar's response was a bit more correct, but still wrong #-o .

Sometime later when belmont was turned out instead it became " kays".
I guess you had to be there.

Re: General fire discussions

Posted: Sat Jan 31, 2009 9:04 pm
by written_ficton
Approx 1am this morning Daglish 1st reported to an alarm at UWA...

False alarm

Re: General fire discussions

Posted: Sat Jan 31, 2009 9:07 pm
by Leigh
Have heard about 15 DBAs while listening to the scanner today, i think the closest one to a fire was burnt toast.

Re: General fire discussions

Posted: Sat Jan 31, 2009 9:42 pm
by newbie
the lightning tends to set them off

Re: General fire discussions

Posted: Sun Feb 01, 2009 9:13 am
by Fastlane
newbie wrote:the lightning tends to set them off
Not true. It's usually water getting into the detectors when we have a big storm.

Re: General fire discussions

Posted: Sun Feb 01, 2009 9:37 am
by Toottoot
Fastlane wrote:
newbie wrote:the lightning tends to set them off
Not true. It's usually water getting into the detectors when we have a big storm.
Sorry, it is true. Most of the time it is voltage fluctuations that cause erroneous signals but large fluctuations cause sudden death of the sensors. Water will more likely cause sudden death of the detectors than erroneous signals.

Re: General fire discussions

Posted: Sun Feb 01, 2009 10:14 am
by robbage
Would it be fair to say that water incursion and lightning activity both contribute to equipment failure?

Re: General fire discussions

Posted: Sun Feb 01, 2009 10:48 am
by Fastlane
Have a listen when we next have a big storm. You'll hear "water in the detector head" quite alot. I'm doubtful that a critical system such as a fire control panel would fall prey to fluctuating AC voltage (and in that case, they all have DC battery backup) that results in erroneous zone activations. If you've ever taken a look at the voltage on a power point, you'll see it fluctuates quite a bit all the time.

Re: General fire discussions

Posted: Sun Feb 01, 2009 11:32 am
by Toottoot
Fastlane wrote:Have a listen when we next have a big storm. You'll hear "water in the detector head" quite alot. I'm doubtful that a critical system such as a fire control panel would fall prey to fluctuating AC voltage (and in that case, they all have DC battery backup) that results in erroneous zone activations. If you've ever taken a look at the voltage on a power point, you'll see it fluctuates quite a bit all the time.
I have heard 'no fault found - left in the hands of the owner' more than 'water in the detector head'. All manner of critical systems fall victim to fluctuating AC voltage and these surge voltages can break over making it through DC regulators at times. I will admit a good filter does help, but lightning is an unpredictable beast.

I have on many occasions taken a look at the voltage at a power point as well as voltages at switchboards, power filters, voltage regulators/surge suppressors, lighting points, motors, resistive loads and the like and by the very virtue of its nature, alternating, the AC voltage fluctuates normally. It does however fluctuate to values outside the safe parameters during lightning storms or other fault events.

Re: General fire discussions

Posted: Sun Feb 01, 2009 11:45 am
by Fastlane
Toottoot wrote:"and by the very virtue of its nature, alternating, the AC voltage fluctuates normally"
'alternating' is in relation to the direction of current flow, has nothing to do with the voltage? <-- call that high school teachings (thankyou robbage)

btw, it's not up to the attending crew to determine what a fault is. It's either a valid alarm (even if its caused by water ingress) or a panel fault. I'm talking generally, about what I've heard in the past 8 years. Crews get turned out to alarm calls, not to 'panel fault' indications or panels offline.

Re: General fire discussions

Posted: Sun Feb 01, 2009 11:49 am
by robbage
Fastlane wrote:Have a listen when we next have a big storm. You'll hear "water in the detector head" quite alot. I'm doubtful that a critical system such as a fire control panel would fall prey to fluctuating AC voltage (and in that case, they all have DC battery backup) that results in erroneous zone activations. If you've ever taken a look at the voltage on a power point, you'll see it fluctuates quite a bit all the time.
The company I work for contract to defence including all the panels and boards. There have been quite a few cases of lightning damage. We are required to provide reasonable proof that it is lightning, including weather reports etc. You can never have guaranteed protection from lightning. A few years ago at my facility, we lost several hundred thousand dollars in equipment (nothing to do with fire) due to lightning. Even with 18 lightning arrestors, mains surge diverters, data line protection, several hundred metres of underground lightning system and the main roof protected, we still get affected by lightning. The computer running the equipment usually freezes when there's a nearby strike.

Also, AC current alternates because the voltage alternates :)