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