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🔌General Home Automation => Automating Your House => Troubleshooting Automation Problems => Topic started by: Biooya on February 16, 2013, 07:33:55 PM

Title: Troublesome Circuit Isolated, But Source Not Clear
Post by: Biooya on February 16, 2013, 07:33:55 PM
Edit, just to clarify: with this circuit on, even with an XTB-IIR installed, X10 isn't working on any circuit. Flip the break off, X10 works great.

Flipping each circuit breaker off one at a time, I've isolated the troublesome circuit. With the breaker off, X10 works great through-out the house. However, there is nothing on that circuit except two receptacles and some incandescent lights (no CFLs, no electronics.) Nothing is plugged into the receptacles on that circuit. All lights on that circuit are turned off. Using a 3 prong receptacle tester, there is no ground on the outlets. This is not surprising however, since this is an older house and most of the circuits have no ground wire (but the X10 works fine on the other circuits, so long this particular circuit is off.)

Any suggestions as to what could be causing this?
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: JeffVolp on February 17, 2013, 11:33:02 AM

Since the XTB-IIR would solve the problem of weak signal levels, there must be a noise source somewhere on that circuit that is blocking X10 transmissions.

If you have a manual controller, try plugging it into the X10 Boost input and see if your X10 devices still function with that circuit still powered.

It isn't clear what controller you are using.  A "polite" controller like the CM15A will not transmit if it believes there is already X10 activity on the powerline.  Some noise sources can produce noise similar enough to X10 transmissions to cause that to happen.

If you have a CM11A or CM15A plugged into the X10 Boost input on the XTB-IIR, try plugging into an adjacent wall outlet.  The return signal amplifier in the XTB-IIR can amplify in-band powerline noise, and make it look more like an X10 signal.  (There is a mode option to reduce that effect, but it reduces its sensitivity as a repeater.)

Jeff
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: Brian H on February 17, 2013, 03:11:34 PM
Since you have a two wire branch circuits with no safety grounds.
By chance are the breakers a GFI type?
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: dave w on February 17, 2013, 04:07:57 PM
Nothing is plugged into the receptacles on that circuit. All lights on that circuit are turned off.
Yeah I too have said that with confidence, only to find that a circuit snaked around the house and fed something I did not know it fed. I have a circuit the feeds a bedroom, then runs across the house and while well hidden, feeds a water softener. Who knew? and why did it power something on the other side of the house and nothing in between??? (rhetorical, I know the answer and not important to this).
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: Biooya on February 18, 2013, 02:08:34 PM
Dave W got it right. After removing the receptacles & switches and tracing wires, I found one hot/neutral pair that didn't seem necessary and when disconnected all worked fine. Ends-up there was a receptacle hidden in the attic (behind some clutter), in which was plugged a long-forgotten and apparently faulty Radio Shack 61-2676 X10 wireless receiver (its probably been there for 18 years.) Removed and all is well again.

Thank you all for the suggestions

P.S. The XBR-IIR is a great device!
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: dhouston on February 18, 2013, 03:53:24 PM
I'm not familiar with the model number but, if it was that old, it may have been the earlier design that waited for a rising ZC to send PLC. Although I think they were much older than 18 years, that would guarantee collisions with any transceiver on the opposite or same phase. Newer design transceivers transmit on the next ZC regardless of polarity, minimizing collisions. Older, brown, Magnavox transceivers were frequent culprits when mixed with newer TM751 transceivers.

I did some extensive collision testing several tears ago. I could not induce collisions with newer TM751s, RR501s would wait for a free line but would give up after a few tries. The CM11A did fairly well, IIRC, as did the CM15A but I did not test it extensively as I had already decided not to waste any time with  X10's firmware or software which I considered atrociously amateurish.
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: Brian H on February 18, 2013, 06:33:12 PM
Glad you found the problem.
I did a whole house circuit map and found a few odd things myself.
I have a single outlet that goes On and Off with the furnace breaker.  ::)
Title: Re: Troublesome Circuit Isolated, But Source Not Clear
Post by: Noam on February 19, 2013, 02:53:58 PM
...I have a single outlet that goes On and Off with the furnace breaker. ...

If that outlet is near the furnace, perhaps it may have been used for a humidifier and/or a condensate pump at one time. If it is not near the furnace, it may have been used in the past for some other HVAC-related equipment that was supposed to be turned off when the furnace was being serviced.