Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Noam]

...this may be a difficult one to solve.

Jeff -
I'm waiting to see what you come up with. You always seem to come up with really creative solutions to these types of problems (and then prefix them with "XTB-" ).

[JeffreyB]

I wonder about the effectiveness of the PZZ01 or Leviton 6284.

I've got one and it doesn't knock it down enough to eliminate the problems...

Jeff

[JeffVolp]

I wonder about the effectiveness of the PZZ01 or Leviton 6284.

I've got one and it doesn't knock it down enough to eliminate the problems...

But maybe it will help with that 1 ohm source impedance that will be pretty difficult to deal with.

Jeff

[JeffVolp]

...this may be a difficult one to solve.

Jeff -
I'm waiting to see what you come up with. You always seem to come up with really creative solutions to these types of problems (and then prefix them with "XTB-" ).

I've got a computer spice simulation running for a noise eliminator.  Unfortunately, the output driver (Elantec EL2009) appears to have been discontinued, and I have to find a currently available equivalent.
 
Jeff

[Noam]

... Unfortunately, the output driver (Elantec EL2009) appears to have been discontinued, and I have to find a currently available equivalent.

Or design your own...

[JeffVolp]

... Unfortunately, the output driver (Elantec EL2009) appears to have been discontinued, and I have to find a currently available equivalent.

Or design your own...

Replacing an integrated circuit with dozens of discrete components is not cost effective.

Jeff

[Noam]

... Unfortunately, the output driver (Elantec EL2009) appears to have been discontinued, and I have to find a currently available equivalent.

Or design your own...

Replacing an integrated circuit with dozens of discrete components is not cost effective.

Jeff

Sorry, it sounded like you only needed it to make a noise generator for testing. I figured "discrete components" would be a reasonable solution for a one-off application like that.

[JeffVolp]

... Unfortunately, the output driver (Elantec EL2009) appears to have been discontinued, and I have to find a currently available equivalent.

Or design your own...

Replacing an integrated circuit with dozens of discrete components is not cost effective.

Jeff

Sorry, it sounded like you only needed it to make a noise generator for testing. I figured "discrete components" would be a reasonable solution for a one-off application like that.

No, I need something for the "production" unit.  I haven't been able to find anything available today that is as good as the EL2009.  Here is a quote I found during my search:

"The long out of production EL2009 is the king of buffers."

And actually, I would like something a little better.

Jeff

[dhouston]

Might this work?

• http://www.ti.com/lit/ds/symlink/buf634.pdf

[JeffVolp]

Might this work?

• http://www.ti.com/lit/ds/symlink/buf634.pdf

I'm afraid not.  I've searched all the normal manufacturer websites for something suitable.  I should have a spec sheet coming from Intersil for a device that might do the job.

The problem is the smart meter "noise source" can have a 1 ohm output impedance, and will deliver 1 amp.  And there is an alternate LonWorks transceiver that can deliver 2 amps.  So it will take a real beefy driver to null out that signal.  The EL2009 can drive 1 amp, but even that unit doesn't do well into the 1 ohm source impedance.  From the TDK data sheets, it looks like a couple of the ferrite doughnuts over the power leads can add another ohm or two at 100KHz so something like the EL2009 can do the job.

Even though the EL2009 was discontinued a decade ago when Elantec was bought by Intersil, there are still some available in the "obsolete" market at about $30 a pop.  But I would not rely on that source for a new product.

Jeff

[Noam]

Is there any way to isolate the signal, and keep it from coming into the house?
I'm sure a giant UPS would do it (use the utility power to keep some very large batteries charged, run everything off those), but would probably be expensive, and not very efficient.

I'm no engineer, but is there something that could be placed in-line (perhaps only on those circuits that need it) to block those type of signals? (just guessing here)

[JeffVolp]

Is there any way to isolate the signal, and keep it from coming into the house?

Yes, but I don't think that is the plan here.  I think the utility companies eventually want to control equipment in homes through their smart meters so they can turn off your A/C and other heavy loads during peak periods.

To prevent the signal from coming into the home, it would take two 200A notch filters tuned to the frequency of the meter.  Think of two filters an order of magnitude bigger than the X10 XPF.

Something I recommended to another fellow who was dealing with an insurmountable noise problem was to take his X10 system private.  Essentially, that would isolate all X10 circuits from the main distribution panel, and then use signal couplers between the isolated phases.  Something like that may be feasible in smaller X10 installations.

Jeff

[dhouston]

Something I recommended to another fellow who was dealing with an insurmountable noise problem was to take his X10 system private.  Essentially, that would isolate all X10 circuits from the main distribution panel, and then use signal couplers between the isolated phases.  Something like that may be feasible in smaller X10 installations.

Sounds like Lightolier's Compose system with its (expensive) firewalls.

[JeffVolp]

A follow up on the BUF634:

That device is not included in my simulator's library, but I did a sim with the similar Harris HA-5002.  Using a bank of 5 devices, a 10Vpp signal with 1 ohm source resistance is nulled to about 75mVpp.  It takes some serious power to do that, but this appears to be a viable way to deal with the smart meter problem.

Jeff

[Noam]

A follow up on the BUF634:

That device is not included in my simulator's library, but I did a sim with the similar Harris HA-5002.  Using a bank of 5 devices, a 10Vpp signal with 1 ohm source resistance is nulled to about 75mVpp.  It takes some serious power to do that, but this appears to be a viable way to deal with the smart meter problem.

Jeff

See? I knew you could do it!

Keep up the good work.