UPB on Generator

[apostolakisl]

UPB puts the signal at the zero cross, right? I believe it is the same in that respect to x10 and Insteon.

So, in theory, only issues at the zero cross should affect upb signal integrity. So, in theory, a poorly shaped wave form or clipped waves shouldn't affect signal quality provided the zero crossing point is clean. That brings me to my point, couldn't the problem just be noise at the zero cross? If so, how about a noise filter?

 

[video321]

UPB puts the signal at the zero cross, right? I believe it is the same in that respect to x10 and Insteon.

So, in theory, only issues at the zero cross should affect upb signal integrity. So, in theory, a poorly shaped wave form or clipped waves shouldn't affect signal quality provided the zero crossing point is clean. That brings me to my point, couldn't the problem just be noise at the zero cross? If so, how about a noise filter?

I don't know anything about the inner-workings of UPB, but clipping a sine wave also creates harmonics - which would cause a lot of issues depending on the severity. The issue then becomes how much is the generator creating? There are white papers noting how complex HVAC systems won't even fire up unless there is less than 5% and I've seen measurements of 25+ for a typical generator. So you'd be looking for an inverter-type or one that specifies low THD.

 

[apostolakisl]

I think there are potentially two different issues.

1) Power Line Communication
2) Electricity for the UPB switch itself

Is the failure of the switch to operate properly one, the other, or both?

It would be worth asking if the UPB switches operate at all. In other words, does a local load turn on? Do the LED's turn on and do all the normal stuff. Certainly if a switch can't control a local load, the problem is bigger than power line noise.

 

[drozwood90]

UPB puts the signal at the zero cross, right? I believe it is the same in that respect to x10 and Insteon.

So, in theory, only issues at the zero cross should affect upb signal integrity. So, in theory, a poorly shaped wave form or clipped waves shouldn't affect signal quality provided the zero crossing point is clean. That brings me to my point, couldn't the problem just be noise at the zero cross? If so, how about a noise filter?

UPB uses a LOT more than X10 did...and it communicates all over the sinewave...not just a the 0 cross (which I think they don't touch...they only use the zero cross for timing the signals).

They actually use an RF receiver inside the switch to pickup the RF pattern on the line. Basically, anything in the RF spectrum that gets folded into the frequencies they care about (clipping a sinewave will do this, as stated in another post here), will cause the switch to become essentially deaf. That was what the claim about Gen2 switches are. They are more tolerant of noise.

--Dan

 

[HAI_fjh]

If you really want to learn about UPB, go to http://pulseworx.com/ and read about how the technology works. They have several documents targeted at various levels of understanding...

UPB puts precise pulses, not RF, at precise points on the sine wave. The data rate is about 5 times that of X-10. Some claim up to 20 times faster, but that depends on wether you are counting baud rate or actual commands per second. In any rate it is faster and less prone to noise than X-10, BUT does require a fairly stable sine wave.

In a small inexpensive generator under load the frequency can vary greatly and the sine waves can be quite distorted. Incandescent light bulbs don't care about this, but a lot of electronics and some motors do care.

Some generators try to condition and regulate the power by using inverters to produce a more stable sine wave. This works to varying degrees. In general the more you spend on a generator the better they do.

Poor sine waves can affect the ability of UPB (and other PLC based technologies) to communicate. But more than this unstable power can affect any load that is switched by TRIACs, this includes "dumb" dimmers...

OK so what is the answer? A better generator or a different lighting system?

FWIW: I live in Louisiana and we see a fair amount of hurricanes and power outages. In my case, I know people who have nice whole house generators that work well. For me I decided that the cost was not worth the benefit. If a bad storm comes I evacuate and come back when the power is on. For a couple of lesser storms I have stuck it out and used a small (5.5 KW) generator to run the fridge, freezer, a few lights and some fans. At just over 1 gallon per hour I spent a LOT on fuel for the generator, I was still hot, with no internet or cable, and the mosquitoes nearly ate us alive.

I think from now on I am just going to evacuate, and work from an air conditioned hotel room.

If you really want to explore a whole house generator, READ then contact the manufacturer or an authorized dealer. Ask specific questions and ask for references of others who are using the product you are considering. Talk to the users. Calculate not only the cost of the generator and the installation, but the operational costs. Make sure you do it right (safely). Every time there is a bad storm with a long power outage we hear about someone who has had a bad or fatal experience with DIY generator project.

For me it just didn't add up. I have been in my current home for 17 years. I have evacuated 4 times. Usually for a few days to a week. For Katrina it was 3+ weeks. This just wasn't worth a $15K - $20K investment.

 

[drozwood90]

Fred, great explanation. I was not saying they PUT RF on the line...I was attempting to say that what is used is a RF part to pickup the signals. (last I saw, it was a PIC from the RF-PIC line from Microchip).

Sorry for any confusion.

--Dan