Re: Fire Lite MS5024UD

[Jim Rojas <jrojas@xxxxxxxxxxxx>]

On 11/28/2014 11:11 PM, ABLE1 wrote:
> "Jim Rojas" <jrojas@xxxxxxxxxxxx> wrote in message
> news:PFaew.733456$Ub6.46948@xxxxxxxxxxx
>> On 11/28/2014 9:08 PM, ABLE1 wrote:
>>> Ok, So just to spark a few post here I thought I would share
>>> my latest challenge.  And to maybe get some insight at the same time.
>>>
>>> I have just inherited a MS5024UD panel.  Trying to evaluate the
>>> problem has become a problem.  Panel is showing a F 4 trouble.
>>>
>>> According to the manual this is a Fault on Zone 4.  Cool that was easy.
>>>
>>> Well when I check the resistance of the loop I get 4.76k worth.
>>> That is correct.  I placed a 4.7K resistor across the zone.  No Change.
>>>
>>> My thought is that the mother board has a problem with Zone 4 OR the
>>> panel has some program issue that is causing the fault.
>>>
>>> So my question is:
>>> Any of you guys know anything about this panel enough to give some
>>> insight??
>>>
>>> Thanks,
>>>
>>> Les
>>>
>>>
>>
>> I use to field repair hundreds of fire panels before NFPA72 stated we
>> couldn't do it anymore.
>>
>> I am assuming you removed the field wiring before you put the resistor
>> across it? Did you swap zones around? Try swapping zone 3 & zone 4. (make
>> sure you are swapping same class zones (Class A or Class B)
>>
>> If yes, the panel most likely took a strike or a surge on that zone. It is
>> a very common problem. There is a diode or resistor on the board near the
>> zone. It is most likely an SMD diode. If not, use a meter and test the
>> diode. They are designed to blow to save the panel.
>>
>> Remove field wiring on zone 3 & 4 (Must be same Class). Then take a
>> voltage reading across zone 3. Then take a voltage reading across zone 4.
>> This will help to determine if it is a field wiring problem or the panel.
>>
>> I can't tell you how many times in my 30 years I have walked on a huge
>> fire system service call with nothing more than a meter, soldering iron
>> and a box full of parts, and start replacing common components that fail.
>>
>> It is a lost art, just like window foiling... :)
>>
>> Jim Rojas
>
> Hi Jim,
>
> Thanks for the response.
>
> No I did not swap the field wiring.  With the values I had I did not see the
> point.
> I did look closely to the components on the board but did not see where
> there
> was any evidence of a problem.
> I know it is most times never easy to see where the smoke escaped.  :-)
>
> My guess, as I said, that the board has an issue.  Mostly likely a strike as
> you said.
> I am not interested in trying a repair.   But I will do as you suggest and
> check
> the voltage just to prove that the board is the problem.  Thanks for that
> tip.
>
> I was just wondering if there was a possibility
> of a program issue that could cause the Fault in some way.
>
> System was installed in 1996 and has seen better days.  My choices are going
> to be
> limited to the install of a MS-5UD3.  The current wiring plan of the system
> has 2 wire smokes as well as Heat & Pull Stations on the same zone.  This
> limits
> my choice of panels available to use this wiring scheme.
>
> Thanks again and have a good weekend.
>
> Did it get a bit chilly last week??  Sorry I left the rear door open.  ;-)
>
> Les
>
>

I enjoyed the changed in weather...thanks!

Jim Rojas