Author Topic: Anomalous data and PLC interference  (Read 2955 times)

birdfeedr

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Anomalous data and PLC interference
« on: August 09, 2012, 01:34:09 PM »
I have a single MTU monitoring line power, no alternate power hookup. Gateway 1.0.454, Daughterboard 1.0.27, Footprints 1.0.245, MTU 1.0.57 Fairly old firmware versions, current from 2009.

Hour history shows flat line values for several hours at a time. So then I observe stats display, and see that the page refreshes, sometimes every second or so, then sometimes many seconds before refresh. I notice MTU Skp increments occasionally. And I read in the forum that this is indication of interference. I have been paying closer attention to the stats page the last few weeks, rebooting the gateway to start a new count for observation.

So, a couple of questions for those with more experience:

1. If I divide seconds Uptime by MTU Rec, I generally get 12 seconds on average. This seems high. Is it?

2. MTU connection is 120/240 (blk, red, wht). A phone call to support suggested the first thing is to go 120 (blk, wht). Is there a downside to only monitoring L1 or L2?

3. Right now, the MTU connects to a double pole breaker and the gateway is on a utility circuit at the panel (different breaker). I plan to add a breaker and circuit which is dedicated to the MTU and gateway with no other devices connected. This seems to be the current thinking. Did I read the forum right?

4. Interference can come from a variety of sources. If I flip breakers off, and notice a change in stats display, I've found the source. Can I get interference from my neighbor connected to the same transformer, and if yes, how do I filter that?

5. If something in my house is the source of interference, will a single filter on the dedicated MTU/gateway circuit be sufficient?

6. What single filter would I use? TED's link to Accessories seems to be broken. Can someone identify a filter that worked for them?

7. Should I upgrade to latest firmware?

Thanks in advance for your help.
« Last Edit: August 09, 2012, 01:53:50 PM by birdfeedr »

Support7

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Re: Anomalous data and PLC interference
« Reply #1 on: August 09, 2012, 05:49:24 PM »
Good morning Birdfeedr, I've posted answers below your questions in bold.


1. If I divide seconds Uptime by MTU Rec, I generally get 12 seconds on average. This seems high. Is it?

Yes. Additionally a MTU REC to SKP ratio higher than ~20% could be indicative of PLC interference.

2. MTU connection is 120/240 (blk, red, wht). A phone call to support suggested the first thing is to go 120 (blk, wht). Is there a downside to only monitoring L1 or L2?

Power it 120V for better signal on the same circuit or same leg: www.theenergydetective.com/troubleshooting

3. Right now, the MTU connects to a double pole breaker and the gateway is on a utility circuit at the panel (different breaker). I plan to add a breaker and circuit which is dedicated to the MTU and gateway with no other devices connected. This seems to be the current thinking. Did I read the forum right?

Yes. Ideally you would power the Gateway from the same circuit as the MTU is on for best PLC communication. Also see filters video on above troubleshooting link.

4. Interference can come from a variety of sources. If I flip breakers off, and notice a change in stats display, I've found the source. Can I get interference from my neighbor connected to the same transformer, and if yes, how do I filter that?

Yes. Reference the above troubleshooting link on filters.

5. If something in my house is the source of interference, will a single filter on the dedicated MTU/gateway circuit be sufficient?

Yes, if the circuit is isolated with the filter from the device causing interference.

6. What single filter would I use? TED's link to Accessories seems to be broken. Can someone identify a filter that worked for them?

http://www.ebay.com/itm/XPF-20A-Wired-In-Noise-Filter-X10-PRO-/150440793381?pt=LH_DefaultDomain_0&hash=item2306f85525

7. Should I upgrade to latest firmware?

As always, we recommend that users do not upgrade unless there is a specific feature or bugfix that is applicable.

I hope this answers your questions. Thank you for your post!

TED Support
« Last Edit: August 09, 2012, 05:51:14 PM by Support7 »

RussellH

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Re: Anomalous data and PLC interference
« Reply #2 on: August 09, 2012, 08:57:20 PM »
2. MTU connection is 120/240 (blk, red, wht). A phone call to support suggested the first thing is to go 120 (blk, wht). Is there a downside to only monitoring L1 or L2?

Power is a function of voltage.  The MTU uses the power connection to measure the voltage.  If you connect both legs, then you are averaging the two phases, but will be dividing the signal across both legs.  By connecting to only one leg, you're assuming that both are the same voltage.  More then likely, for most practical purposes, that's a safe assumption.

3. Right now, the MTU connects to a double pole breaker and the gateway is on a utility circuit at the panel (different breaker). I plan to add a breaker and circuit which is dedicated to the MTU and gateway with no other devices connected. This seems to be the current thinking. Did I read the forum right?

That gets the strongest signal possible to the gateway.  If you also filter that circuit (connecting the MTU and the gateway to the filtered side), then you're safe from any interference.


Can I get interference from my neighbor connected to the same transformer, and if yes, how do I filter that?

Yes.  Use a filtered circuit as mentioned above.


dane1234

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