Re: Complicated Napco MA2600 Internals Issue

["Jim" <alarminex@xxxxxxx>]

On Feb 27, 12:44=EF=BF=BDam, "Katie Wasserman" <katie10...@xxxxxxxxx> wrote:
> I've been reading some of the expert posts here and I know that you're
> the right group for this one.....
>
> I have a Napco MA2600 system in my house and find that it generates a
> lot of RF noise from below 300KHz up to 2MHz. =A0Bad enough for
> listening to AM radio but I recently got interested in ham radio and
> that makes the problem much worse. =A0 The RF noise is coming not just
> from the AC line but from all the contact wiring throughout the house
> so it's not easy to get rid of.
>
> My solution is to shut down the alarm system completely and although
> this works it's a pain to bring it up and down so I've set up a system
> to do that remotely. =A0The "system" is a remotely control relay that
> cuts off the low voltage AC into the control panel and simultaneously
> the 12V battery supply. =A0The cutoff function works great! =A0But when
> the system powers back up it sets off the alarm unless the AC is
> applied first followed by a delay of a few seconds then the 12V
> battery can be connected up.
>
> I suppose the I could ehnace my relay circuit to add the needed delay,
> but I just assume not even bother with the 12V battery and run the
> system without that. =A0Of course you can't just pull the battery on
> this system since the controller is busy with alternately charging and
> checking it all the time and if it finds it's not there it won't let
> you arm it. =A0There's no detail on the charging/checking battery system
> in the manual. =A0If I had a schematic I'm sure that I could figure it
> out but finding one seems to be an impossible task.
>
> So I'm looking for ideas along the lines of one of these, or maybe
> something entirely different.
>
> 1) =A0There's obviously an "AC power good, ready to accept 12V battery
> voltage" signal somewhere in the panel. =A0If I can access that point I
> can use it to control the relay for the 12V battery and not use a
> fixed (and unreliable) time delay. =A0Where is it? There's some mention
> of an optional PS3002 power supply that hooks into the control panel
> through lugs E7 an E18. =A0Could one of these be the point that I'm
> looking for, I haven't done any circuit probing yet.
>
> 2) =A0Faking out the battery check with a dummy battery of some sort
> doesn't seem to be a workable solution, since if it really thought the
> battery wasn't =A0there when the AC power was applied it would set of
> the alarm. Turning off the battery check completely seems like it
> would work but I have no idea how to do this.
>
> 3) Find some magical way to eliminate the RF noise.
>
> 4) Throw the whole thing out and buy a different system.
>
> Thanks,
>
> Katie

I don't know how your system is programed but if it isn't programed to
alert on AC fail, just get a power supply with a back up battery and
power the system through the battery terminals only. No AC to the
panel at all. Do you have access to the dealer programing? If you do,
and the system is giving you an AC fail signal, I think you can
program it to not alert to an AC power failure. I'd have to check the
manual to be sure, however. Let me know if you have access.

If not, some panels can be fooled into thinking that AC is applied
just by applying 12 VDC to one of the AC terminals. I don't remember
if the 2600 can do this or not. You may have to follow some circuitry
on the board to find out if they're using a bridge rectifier or not or
which of the AC terminals to use.