Print

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

[joao.prates]

Hi all.

Here's my scenario:

I've a 3 phase electrical system at my house, a standard European 380 v (3 x 220) system.
I've 2 switch boards, one main one at the house entrance, and another switch board that is fed from the main board and isolates the "heavy weight" machinery into its own switch board.

At my house entrance I've 3 x FD10 phase couplers / filters.

My heat pump (HP) operates using the 3 phases, and it is fed from the secondary switch board.
This HP just fries any X-10 module within a certain range of proximity with line noise as soon as it is connected.
I'm also having problems with a Grundfos water pump, with the same behaviour, and also connected to this second switch board.

If I power off the heat pump and the water pump, or if I turn the switch board off for them, the x-10 modules near them work fine.
With the power on at the heat pump or the water pump, the X-10 modules in the proximity just play dead.

Due to this problems, I'm trying to isolate the secondary switch board, i.e. make it look as if outside the house, out of X-10 range.
If I can isolate it's noise, I'll be ok, since I do not wish to control with X-10 any of the machinery that is fed from there.

I've tried to use a second set of FD-10 phase-coupling and filter modules connected at the switch board entry lines.
In this try I did not connect the K lines, no coupling, just the L lines to do filtering at the secondary switch board.
It solved the Grundfos problem, not the HP problem, maybe the interference from the HP is just way too big for the FD-10 to handle?

However, I'm having second thoughts about the direction of the phase line.
If the filters at my house entry are filtering the signals from outside, shouldn't I connect these ones inside the house in reverse?
What I mean is, shouldn't I connect the phase lines coming from the main switch board to the LINE OUT in the FD-10 instead of LINE IN?

What do you suggest in this case scenario?


Thanks,

Joćo Prates

[JeffVolp]

I couldn't find a schematic of the FD-10.  X10 uses two filter different technologies: notch and low-pass.  A notch filter attenuates a certain band of frequencies, and is usually bidirectional.  A low-pass filter attenuates frequencies above a certain point, and is usually unidirectional.

The specs on the FD-10 indicate it is a notch filter.  Outgoing attenuation is 15dB, and incoming attenuation is 15-20dB, depending on how much current is flowing through it.  (The higher number is with no current.)  So you might pick up a little more attenuation by reversing the direction, but I suspect it will not really make any difference.

It sounds like your heat pump creates enough noise that 15dB attenuation is not sufficient.  I recall a report from someone who had a similar problem with a fluorescent light electronic ballast.  I believe that was resolved by cascading a second filter in series.  While an expensive option for you, that might be something to try.

The ideal solution would be to move the feed for that second panel before the X10 filters on your primary panel.  That would place the two sets filters in series with respect to the path between your heat pump and your X10 system.

Jeff