Re: Telco Line Fault??

["John R. Sowden" <jsowden@xxxxxxxxxxxxxxxxxx>]

ABLE1 wrote:

> Hey to all,
>
> I installed a new Fireworx FX-64RD panel a couple of months ago.
Almost
> from day one started to receive sporadic Telco Line Faults.  Both
Line 1
> and
> Line 2.  Little correlation can be determined except it happens 9
times
> out
> of 10 during the week Monday - Friday and during the day 9am to 5
pm.  In
> other words 90% of the time during working hours.  (aka when the
phone are
> likely to be used)
>
> It happens 1 to 3 times in a given day and then skip a day or two.
>
> It was originally connected  to their Line 1 and Fax Line, I have
moved to
> L-1 and L-3 no help.  It is now on L-1 and L-2 and am waiting to see
how
> it
> goes.  Line 1 happens less frequent so I have left it alone.
>
> In calling UTC Tech Support...........................  I was told
that
> the threshold voltage is 10vdc.
>
> I have gotten the 10vdc from a couple of different techs so that
must be
> the
> number but it seems to be on high side.  I remember on a burg panel
that I
> was having a problem a couple of years ago I was told the threshold
was
> 6vdc.
>
> What I am reading at the panel is 6.5 to 7.5vdc when a phone is off
hook.
> So if the threshold is 10vdc then the panel is going to go into
trouble
> after the timeout of 2 minutes which is the maximum.
>
> The lines that I am working with are (what I think is) POTS lines on
> copper. However I was told that if there is a digital converter?? it
could
> cause
> some trouble.  How do I determine if this is the case???
>
> Has anyone here experienced this??  Especially on this panel??
>
> Any additional thoughts that may help would be appreciated.
>
> TIA
>
> Les
Regarding the voltage, on hook telco is about 50 volts (48 volt
batteries in the CO plus the excess to charge them).
Re the troubles, check to see if any prem phones have been installed
onto the ring and tip terminals instead of the output of the RJ.  Some
panels look for a current flow when the voltage drops to the off-hook
level.  If there is no phone off hook on the RJ output, then there is
no current flow.  If you take an ohmmeter reading from tip in to tip
out, and ring in to ring out, you might see a small ohms difference.
This is the sense resistor that the panel is reading a voltage across
to determine if there is a current flow (ohm's law).  The problem is
that telco people put their things on ring and tip, disregarding the
RJ hookup.

Hope this helps.
John Sowden
American Sentry