Re: Need to cut through the BS on Alarm monitoring costs

[blueman <NOSPAM@xxxxxxxxxx>]

Robert Macy <robert.a.macy@xxxxxxxxx> writes:

> On Feb 4, 10:05Â pm, blueman <NOS...@xxxxxxxxxx> wrote:
> ...snip...
>> Well, the 'uneducated' installers at my alarm company are taught to
>> twist and solder. Unfortunately, the ones that did my installation were
>> lazy and "forgot" to even solder about half the connections -- they were
>> just twisted. So by going back and soldering the joints, all I did was
>> bring the installation up to the level that the installers are supposed
>> to do according to their training.
>>
>> Unless you are in some type of hostile environment (outdoors, near the
>> sea, chemical exposure), a good mechanical + solder connection should
>> last pretty much indefinitely. How do you think components are connected
>> inside the panel? I have made solder joints 40+ years ago that are still
>> good. If your joints are twisted, soldered, and taped in a 'normal'
>> environment and still failing I call either "bullshit" or that you are
>> not as good at soldering as you think. Perhaps you have some cold solder
>> joints? In 40 years of doing electronics, I have never seen a properly
>> done solder joint fail by itself (of course enough mechanical twisting
>> will break the joint but the wire itself would typical break even
>> ealier). Also, in my experience, CRIMP connections are at least as
>> likely to fail since a lot of people don't do a good job crimping -
>> either too much or too little crimping force or they don't insert the
>> wires properly. Also, a solder joint is both a mechanical and a
>> chemical/welded connection, so it is theoretically electrically superior
>> to a crimp connection.
>>
> ...snip...
>
> I was further told to NOT solder a crimped connection, because it
> undoes the 'goodness' of the connection.  Seems the heat eases the
> spring forces undoing the advantages of a spring loaded connection.
> Telephone companies, do NOT solder ther land wires for same reason.
> always spring forces and crimps.  I always thought that was done
> because the lack of AC power in the field to make a good solder
> connection forced them to rely on these crimp connection, a 'lesser'
> quality connection [in my mind only].

That makes reasonable sense though it is probably hard to generalize
given the variety of non-soldered connection mechanisms out there.

HOWEVER, in my case there was no 'crimp' conector, just twisted
wires. Hence cleaning the twisted wires with flux and adding solder is a
good solution IMHO.

> Yes, I'm aware of solder inside electronic systems. I used to design
> autopilots [somewhat of a major reliability requirement] and telecom
> systems that MUST have 50,000 hours MTBF!  Armed with those
> experiences *and* a university degree I didn't listen to EXPERIENCED
> installers. I KNEW better. W R O N G !  Again, my PERFECT soldered
> connections false alarmed in 1 year external and 10 years internal.
> Going around re-soldering, they all held again for about the same
> amount of time.
>
> For a connection to fail in a security system it only needs to open
> for microseconds, then reconnect for another month.  Most people
> wouldn't even notice that happening inside their CD player, TV, etc.
> And, THAT'S exactly what those solder connections did. False alarm,
> hold several months, false alarm, hold month, false alarm, until got
> down to every week, then re-solder to fix...and last for another 10
> years.

"Connections" on a computer circuit board open for fractions of a
nanosecond and still work. They are also subject to repeated
heating/cooling cycles that are more extreme than a typical single alarm
wire. Also, the vibrations (particularly if there is a fan or hard drive
nearby) are much worse.... yet the solder joint remains supreme...