On Sep 11, 2:58*pm, ml wrote:
hi

a while ago i posted * hoping to get *some *ideas *how to *eliminate *
some s9 noise caused by my buildings new elevators

only took them 9months to install * *some electrical filters *but the
guy doing it *was very nice *and *showed *me a few things

since the filters *didn't help *seemingly at all, * i wanted to provide *
some more information *and see *what *anyone might *think would be
either some *good *tests * to make and or *further corrective *actions

a recap, jan 08 *we got a new *elevator system *the original 1940's unit
was just a rack of relays *there *are 2 elevators * *motor and *stuff in
a small room * rooftop * noise was always *s0 or s1

the new *system *i can see is made by galaxy *believe it or not made in
the bronx ny *i am told they are a large world wide supplier *since i
live in the bronx *at least they are local

my first look * in there today * shows *they did *at least *take pride
in there *work, *all the wiring in there * is *really nice

there is kinda *2 main parts in the cabinet * *a large *pc board *and a *
magnetek HPV 600

i took *my ft817 *shut the other elevator *off * and *moving *the rig *
around *i see i got * no interference from the *computer board *getting
near *the magnetek * big time noise

they have the manual onlinehttp://www.elevatorcontrols.com/downloads/files/hpv600.pdf

pretty interesting * a *section in there *on how to *mitigate *noise *
perhaps a few things in there *i could *maybe double check

when noone is using the elevator *they throw *out some noise *like about *
s2 maybe *more * when the elevator *starts moving *it jumps *naturally
to about *s9

i was wondering *how *to *first see *where the noise *is leaking from *
the metal cabinet *is *pretty *think *i say double the gague *of *say a
file cabnet *, it does *have *slits *on either side *for * air * * a few *
holes *for *conduit * which runs * to the power *and to the motor *

they seemed *to pay attention to grounding * the door *had a *little *
ground *wire on it, * etc *naturally this is all *fast first impression
stuff i didn't have a lot *of time up there

i thought *perhaps * painting the cabinet w/rf paint and getting some *
screens *over the vent slits *thou obv that wouldn't help if it's *
radiating along the conduit *didn't have a chance *to measure for that

the *magnetek *is a bread sized box it gets *hot and has a fan *so i
can't *cover *it, but perhaps a perferated copper/lead *enclousure might
help?(assuming it's not *radiating along its wires)

as a last resort *perhaps *replacing the magnatek w/another brand known
to be *rf quite * *however *i personally don't *know how i would *find
that out *and *no garantee *they would *risk swaping the unit oout

so i am hoping * *that *there might be some brainstorming *and thoughts *
you all might *share?

any advice *tips * * much *appreciated

thanks for all

Elevator motors are DC, in the old one the DC was supplied by a motor/
generator combination, The new ones get their DC from a huge SMPS and
they can be electrically noisy. They can also induce harmonics into
the electrical system that UPSs dont like at all. It is my
understanding the elevator rehab project where I work has been put on
hold for that reason.

Jimmie