Re: Can't Mix Smoke Models....really?

[Frank Olson <Use_the_email_links@xxxxxxxxxxxxxxxxxxxxxx>]

mbbaker@xxxxxxxxx wrote:
> In this case, compatibility is a function of voltage *and* current.
> The smoke detector consumes the same amount of energy always.  If the
> voltage available to the smoke detector sags then current increases
> because energy is conserved (remains constant).  P = IE.  The UL tests
> take these to their logical extremes to determine the failure point.
>
> The literal intent here is that the test only includes one make and
> model at a time.  No one has paid UL to test different combinations of
> devices on the same control.
>
> I agree with you.  Two-wire smoke detectors will shunt the circuit once
> they operate and who cares?  A fire has been reported!  Someone else
> pointed out that this goes to liability.  If I were to mix makes and
> models on the same 2-wire circuit and a tragedy were to occur, I may be
> liable because I knew better than to mix makes and models on the same
> circuit.
>
> Before using common sense in this case, buy errors and ommission
> insurance.
>
> Happy holidays,
>
> Mike
>


Hi Mike:

It's amazing to me that it's taken this long for someone to address this
issue.  There are many installations (Vancouver not being the least of
the cities represented)where "mixing" makes and models of smoke
detectors occurs.  It becomes more and more prevalent as the systems get
older and other servicing companies get involved.  What's really amazing
is that a number of companies aren't aware that smoke detectors are
"cross listed" to a particular control and I've seen numerous
installations where properly labelled detectors (ULC, FM, UL) are "mixed
in" with no thought given to compatibility.  A few of our customers have
gone so far as to request that we not mention it to the apartment
managers if we're called in to service a particular system!!  I've
always responded with: "Would you compromise your own family's safety?
How can you ask us to willingly compromise someone else's??"  Besides
which, my insurance company would have "kittens" and I quite enjoy our
unblemished record (and the low premiums that go with it).