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Old September 11th 08, 07:58 PM posted to rec.radio.amateur.antenna
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Default elevator noise part deaux

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 online
http://www.elevatorcontrols.com/down...les/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
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Old September 11th 08, 09:07 PM posted to rec.radio.amateur.antenna
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Default elevator noise part deaux

On Thu, 11 Sep 2008 14:58:47 -0400, ml wrote:

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


Hi Myles,

One thing that I observed in the PDF you supplied was the Input Power
specification that states:
Line Impedance: 3% without choke / 1% with choke
Check to see if the input power is choked.

73's
Richard Clark, KB7QHC
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Old September 11th 08, 10:45 PM posted to rec.radio.amateur.antenna
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Default elevator noise part deaux

In article ,
Richard Clark wrote:

On Thu, 11 Sep 2008 14:58:47 -0400, ml wrote:

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


Hi Myles,

One thing that I observed in the PDF you supplied was the Input Power
specification that states:
Line Impedance: 3% without choke / 1% with choke
Check to see if the input power is choked.

73's
Richard Clark, KB7QHC


previously i can say there was no chokes power went right into the
unit

today we installed the line filters they have some chokes


i noticed that line, in the manual, not really sure what it means
the power as supplied by con ed is rock solid as far as volts etc
power here is great

maybe i had a rough day , not sure what they mean by impedance
i mean i know what impedance is per say but not applied to 3phase
are they implying that say if one leg is %3 off phase or has
lower voltage or like a spike?



i also checked the pwm settings they were at default


thanks very much for taking a look Rich appreciate it
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Old September 11th 08, 11:44 PM posted to rec.radio.amateur.antenna
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Default elevator noise part deaux

On Thu, 11 Sep 2008 17:45:11 -0400, ml wrote:
previously i can say there was no chokes power went right into the
unit

today we installed the line filters they have some chokes


i noticed that line, in the manual, not really sure what it means
the power as supplied by con ed is rock solid as far as volts etc
power here is great


Hi Myles,

I'm not sure what that specification line means either, but choking is
a standard term for reducing the influence of inductive kick,
something those motors are going to do aggressively and spread RF
trash throughout the spectrum.

However, in the context of motor controllers, solid state triacs can
also be quite noisy and inject trash into the line. This has nothing
to do with Consolidated Edison, except that they, too, could become
annoyed with noise. However, they have a large industrial customer
base that they serve, and they deal with it.

Returning to your desire to add covers, mesh, and the rest. I suspect
that the metal casing already does what it should and requires no
further attention. Instead, it is a matter of the lines that emerge
from those cases that are carrying the noise. They are passing it
along to you through two possible means: radiation or conduction.

If your rig shares the same power line, noise may arrive through that
shared conduction path. This would be part of a ground loop. Barring
that explanation, those lines are radiating like antennas, and their
proximity to your antenna provides over-the-air coupling. This means
you have to reduce that radiation (again, some form of choking, in
this case ferrites) or you move to increase distance and enjoy the
square law (10 times the separation pushes down the noise from S-9 to
S-7 or something like that). Obviously, in your situation, choking is
the simpler, and more effective solution. This will be choking that
is an entirely separate issue from that one line in the manual.

73's
Richard Clark, KB7QHC
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Old September 12th 08, 01:01 AM posted to rec.radio.amateur.antenna
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Default elevator noise part deaux

Richard Clark wrote:
On Thu, 11 Sep 2008 17:45:11 -0400, ml wrote:
previously i can say there was no chokes power went right into the
unit

today we installed the line filters they have some chokes


i noticed that line, in the manual, not really sure what it means
the power as supplied by con ed is rock solid as far as volts etc
power here is great


Hi Myles,

Industrial equipment is often rated in percent or per unit impedance.
http://en.wikipedia.org/wiki/Per-unit_system

For something like this, the impedance is probably mostly reactive. That
is, 1% impedance means a PF of about 0.99 (well, sqrt(1-.01^2).. that
is, you'd draw 1% reactive current.



I'm not sure what that specification line means either, but choking is
a standard term for reducing the influence of inductive kick,
something those motors are going to do aggressively and spread RF
trash throughout the spectrum.

However, in the context of motor controllers, solid state triacs can
also be quite noisy and inject trash into the line. This has nothing
to do with Consolidated Edison, except that they, too, could become
annoyed with noise. However, they have a large industrial customer
base that they serve, and they deal with it.


I would venture that there are no TRIACs in that controller. It's a
standard 3 phase IGBT based inverter drive. The default PWM frequency is
10 kHz, and you'll probably see significant harmonic content at
multiples of that, although CE compliance means that they've filtered a
fair amount out. There's recommendations on page 164 for line filters.
You could probably check with Magnetek for details on conducted
emissions with and without filters.


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Old September 12th 08, 11:51 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jun 2006
Posts: 440
Default elevator noise part deaux

"ml" wrote in message clipped
______________

Just curious, what is your definition of the word "deaux" in your subject
line?

It may help the rest of us to understand you and your post a bit better.


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Old September 13th 08, 12:38 AM posted to rec.radio.amateur.antenna
ml ml is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 225
Default elevator noise part deaux

In article ,
Jim Lux wrote:

Richard Clark wrote:
On Thu, 11 Sep 2008 17:45:11 -0400, ml wrote:
previously i can say there was no chokes power went right into the
unit

today we installed the line filters they have some chokes


i noticed that line, in the manual, not really sure what it means
the power as supplied by con ed is rock solid as far as volts etc
power here is great


Hi Myles,

Industrial equipment is often rated in percent or per unit impedance.
http://en.wikipedia.org/wiki/Per-unit_system

For something like this, the impedance is probably mostly reactive. That
is, 1% impedance means a PF of about 0.99 (well, sqrt(1-.01^2).. that
is, you'd draw 1% reactive current.



I'm not sure what that specification line means either, but choking is
a standard term for reducing the influence of inductive kick,
something those motors are going to do aggressively and spread RF
trash throughout the spectrum.

However, in the context of motor controllers, solid state triacs can
also be quite noisy and inject trash into the line. This has nothing
to do with Consolidated Edison, except that they, too, could become
annoyed with noise. However, they have a large industrial customer
base that they serve, and they deal with it.


I would venture that there are no TRIACs in that controller. It's a
standard 3 phase IGBT based inverter drive. The default PWM frequency is
10 kHz, and you'll probably see significant harmonic content at
multiples of that, although CE compliance means that they've filtered a
fair amount out. There's recommendations on page 164 for line filters.
You could probably check with Magnetek for details on conducted
emissions with and without filters.


thanks for the responce,
as far as filters go my original post specified they just
added filters for me to no avail, hence my post hoping to see if
perhaps somone might have some ideas how to mitigate this type of
noise
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Old September 13th 08, 01:05 AM posted to rec.radio.amateur.antenna
ml ml is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 225
Default elevator noise part deaux

In article ,
Richard Clark wrote:

On Thu, 11 Sep 2008 17:45:11 -0400, ml wrote:
previously i can say there was no chokes power went right into the
unit

today we installed the line filters they have some chokes


i noticed that line, in the manual, not really sure what it means
the power as supplied by con ed is rock solid as far as volts etc
power here is great


Hi Myles,

I'm not sure what that specification line means either, but choking is
a standard term for reducing the influence of inductive kick,
something those motors are going to do aggressively and spread RF
trash throughout the spectrum.

However, in the context of motor controllers, solid state triacs can
also be quite noisy and inject trash into the line. This has nothing
to do with Consolidated Edison, except that they, too, could become
annoyed with noise. However, they have a large industrial customer
base that they serve, and they deal with it.

Returning to your desire to add covers, mesh, and the rest. I suspect
that the metal casing already does what it should and requires no
further attention. Instead, it is a matter of the lines that emerge
from those cases that are carrying the noise. They are passing it
along to you through two possible means: radiation or conduction.

If your rig shares the same power line, noise may arrive through that
shared conduction path. This would be part of a ground loop. Barring
that explanation, those lines are radiating like antennas, and their
proximity to your antenna provides over-the-air coupling. This means
you have to reduce that radiation (again, some form of choking, in
this case ferrites) or you move to increase distance and enjoy the
square law (10 times the separation pushes down the noise from S-9 to
S-7 or something like that). Obviously, in your situation, choking is
the simpler, and more effective solution. This will be choking that
is an entirely separate issue from that one line in the manual.

73's
Richard Clark, KB7QHC


thanks Rich, i think i need to confirm that theory thou it gives
me the willies

my gut tells me that box in the cabinet is where most if nt all the
noise is comming from and while its in a nice metal cabinet its not rf
tight just my gut

the left side has conduit going to the fuse box on the wall for power
on the right side 2 conduits , it goes up to celing almost makes a U
and down to the motor the other some sensor on the motor and break

the cabinet is very close to motor

one thing i did just realize thou it prob effects them more then me,
the guy showed me how they rand the 2 conduits to the motor one for
power one for sensor wires they were about 2 inchs appart he said if
they were in same conduit the'd interfere the manual says it
ougtta be 12" appart hope i am not in the elevator when self
interference occurs egads

the test i made so far was to walk up to the magnateck it was
obviously way noisy i walked over to the motor i didn't test
along the conduit and i didn't test w/the cabnet door closed

and along the cabnet ie the wall of it vs the vent holes

IF i could put some chokes perhaps on the power out put of the
magnatek, the filter unit they added was on the con ed power side
and i might be able to also add some chokes to the control lines to
the motor

what i'd really like to know is if that big filter unit they used can
also be used on the output to the motor i presume thats where the noise
is if it's wire related (my rigs on battery get same noise) i am
afraid to tell the guy to try it as that unit controls the motor
speeds breaking etc

i can only do this inside the cabinet since they are all loose
wires the motor is a sealed box

so assuming , they let me do that, and my test reveils noise
along the wires , what types of snap on chokes /material would
be recomened?

i wonder if they conduit is a 'poor' shield i could easily wrap that
w/rf tape

i can say the noise is s9 from 1.7mhz to 14mhz or so , and from
18mhz up to 28 it starts to drop to s7 on ssb it just sounds like
background noise on 160m or 80 am you also hear a particular
sound every few k that thing works much better as a wide band
transmitter than a motor controller below 1.7 practically no noise

the manual also states if it's default 10khz freq is moved it makes
less noise i suspect the noise would 'shift' i wonder if it
would possibly shift enought to be far enough i mean from 1.8 to
28 is a lot i dunno

on one hand it's kinda complex on the other it's kinda simple if
i was smarter and had the keys /carteblanch to that elevator room



thanks again for all the tips
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Old September 13th 08, 02:04 AM posted to rec.radio.amateur.antenna
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Posts: 88
Default elevator noise part deaux


so assuming * , *they let me do that, * and *my test *reveils *noise *
along the *wires * , *what *types *of snap on *chokes /material would *
be *recomened?

i wonder if they conduit is a 'poor' *shield * i could easily wrap that
w/rf tape


Hi.
I am coming into ths discussion kind of late, but see no mention as to
changes in the noise level as the elevator is operating or not. Is the
motor and control circuit live all the time or just when the elevator
is occupied or in motion.

As far as snap-on ferrite chokes, they must allow the largest wire to
pass and should be fairly large for the low frequency involved.

Perhaps this has been mentioned before, but conduit will certainly
radiate if it is not connected to a common ground point at each end.
Otherwise, it is an antenna. No amount of tape will stop that. If
connected to two "ground" points, the conduit could still radiate as a
loop antenna. The building framework may make an electrical ground,
but not an RF ground.

Do you have a portable am shortwave radio with an external antenna?
Use it to explore (safely!) the wiring with the external antenna. I
did this at home and discovered lots of HF noise coming from a VCR,
DVD player and TV that were always on, but on standby. I think this
exercise will let you track the noise a lot easier than your expensive
ham rig.

Good luck!

Paul, KD7HB
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Old September 13th 08, 10:41 AM posted to rec.radio.amateur.antenna
ml ml is offline
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Posts: 225
Default elevator noise part deaux

hi Paul

see responces below, and thanks very much

In article
,
" wrote:


so assuming * , *they let me do that, * and *my test *reveils *noise *
along the *wires * , *what *types *of snap on *chokes /material would *
be *recomened?

i wonder if they conduit is a 'poor' *shield * i could easily wrap that
w/rf tape


Hi.
I am coming into ths discussion kind of late, but see no mention as to
changes in the noise level as the elevator is operating or not. Is the
motor and control circuit live all the time or just when the elevator
is occupied or in motion.

from being inside my house i can't really tell elevator
movement, i can say the noise is constantly intermittant, that is
on a few min off a few min, it 'seems' not to correspond to
elevator movement but i'd need a second guy to prove that

However being in the elevator room, as previously mentioned w/my
ft817 i can tell you the motor and magnatek is always slightly
energized however with no elevator movement the noise is
extreemly small soo as the motor kicks in the magnatek makes a
ton of noise same test standing ontop of the motor shows little
noise i didn't test the conduit


As far as snap-on ferrite chokes, they must allow the largest wire to
pass and should be fairly large for the low frequency involved.

Perhaps this has been mentioned before, but conduit will certainly
radiate if it is not connected to a common ground point at each end.
Otherwise, it is an antenna. No amount of tape will stop that. If
connected to two "ground" points, the conduit could still radiate as a
loop antenna. The building framework may make an electrical ground,
but not an RF ground.

yea that got me thinking i noticed the manual for the magnatek
actually talked about how to keep one end only 'grounded' and the
book was very good at explaning it, i have to go back up and see if
they did that i bet they sure didn't my guess is they didn't use
shielded wire to the motor sensor i'd guess iether plain wire or if
i am luckey

they have really only an electrical ground up their they did make a
single buss on the bottom and everything terminates at least to a
single point the conduit is 'grounded' by connecting with the metal
cabinet which is connected to that elec ground my building water,
heat, Ibeams and elec ground seem to all be at same potential and do
connect with earth soil, naturally the elevator room on the roof is
14stories high

i disagree with you however that 'no ammount' of tape would help if
the conduit was radiating copper or mu-metal, or lead or RFpaint
wrapped around the conduit and possibly grounded i think would have
an effect but i could be wrong my guess is it could work why do you
think it's not possible?

Do you have a portable am shortwave radio with an external antenna?
Use it to explore (safely!) the wiring with the external antenna. I
did this at home and discovered lots of HF noise coming from a VCR,
DVD player and TV that were always on, but on standby. I think this
exercise will let you track the noise a lot easier than your expensive
ham rig.

Yes the ft817 also has am but i've been testing ssb easier on
the ears and just a strong interference hihi

yeah it's funny how sometimes you find a vcr or a cable modem
that puts out so much noise on even standbuy a lot of companies these
days really are rf poluters and seem to get away with murder

I wonder if that magnetek is legal , just say the unit by itself
is it fcc approved to radiate such a strong signal so broad ??
second to that since it is interfering with a licensed ham station
per rules and regs would it be in violation? i wonder how i
confirm that ultimately i might hve to file a complaignt





Good luck!

Paul, KD7HB

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