PLC solar inverters and UPB

[kurtmccaslin]

I am looking at installing solar panels with SolarBridge microinverters on my garage.   These microinverters communicate their generating status to a central controller using Power Line Carrier (PLC) technology.   UPB modules also communicate vs. PLC.  
 
Does anybody have experience with these systems working in the same house.   Do they conflict?   If they do, is there a way to isolate/filter the signal so that the two systems do not conflict with each other?

 

[kwilcox]

I only have experience with enphase microrinverters. So far, they haven't had any impact on my UPB installation; however I haven't yet installed the Envoy monitoring component. It's very possible that my inverters are only listening currently. I need to find an Envoy that has a 30 day return guarantee since there won't be a way to filter/isolate the communications path due to my parallel metering installation.

What I am using is my TED500 which gives an excellent overall view of array output. I'm not sure at this point whether I even care enough about individual panel performance to shell out north of $500 for the Envoy system.

My TED5000 MTUs along with the footprints module run on their own dedicated branch circuit which is filtered at the panel.

 

[SolarbridgeEmployee]

The SolarBridge PLC system uses Frequency Modulation (AM) and the UPB system uses Pulse-Position Modulation (PPM) so the devices should not interact with each other.  SolarBridge has done informal testing with X10 systems, and there was no interaction. That was with the SolarBridge system in a special test mode that continuously sends out a transmission signal for maximum stress test of the X10 isolation.  While X10 systems send Amplitude Modulation bursts and UPB uses PPM the modulation method (AM) is similar and so the tests have validity.
 
Since SolarBridge systems carry's a warranty of 25years, we recommend that the installation take a longer view with a few simple steps.  Any PLC solar installation will benefit by taking the following steps.  1) Take the solar "home runs" the AC power cables and run them into a solar AC subpanel.  2) Connect the monitoring system to that subpanel.  3) Run an AC cable to your homes AC panel.  This creates a physical separation for PLC signals and then PLC will be better isolated from anything in the 25 year future.
 
On the off chance you so see any problems then a separation filter can be installed between the subpanel and the homes AC panel which will provide electrical isolation for the solar system and the UPB system that will electrical and absolute.
 
25 years is a long, long time for electronics.  Think about what type of computers, internet, and WiFi systems that were used 25 or even 10 years ago and how much it has changed.   By using physical isolation you will harden the solar installation.
 
 

 

[kurtmccaslin]

Thanks for the clear advice!  Much appreciated!!

 

[az1324]

How about insteon and homeplug? What PLC modem technology is SolarBridge using? TI?

 

[SolarbridgeEmployee]

INSTEON uses Modulation: Binary phase-shift keying (BPSK) at 131.65 KHz which is away from our 110KHz  FSK system.  We have not done any testing at SolarBridge but it should work well due to difference in frequencies.  We originally based our technology on ST microsystems, but have made improvements since then.
 
Homeplug is used all the time as the last 300 feet solution to get the Power Manager’s (the monitoring system) ethernet signal to the home router.   The Power Manager and Homeplug system are connected side-by side and work very well. In fact SolarBridge recommends using www.asokatech.com PLC devices because they have a device tailored for solar.  The SolarLink version (http://www.asokatech.com/solarlink-page) operates down to -20C which means you can use it in an unheated garage.  The Power Manager is NEMA 3R and can be mounted outside or in an unheated garage.  No other solar monitoring system can do that without an external enclosure.
 
As with all technologies, the right installation is key for a 25year lifespan.  Physical separation of the solar combiner box will reduce any problems.  
 
One thing,INSTEON-RF uses the same frequency as my pool automation.   However, PLC systems are closed-systems (in house wiring) and therefore separation (and filtering if needed) will absolutely separate solar and home PLC communications for the 25 year warranty life of the solar system.   The fact there is a solution path if needed is great!
 
Finally, do not demand filtering at the start of the design, SolarBridge as has to use filtering just a few times.   Just use separation and you have room for a filter if it is ever needed.

 

[az1324]

Thanks for the information. Link to documentation on the local API?

 

[SolarbridgeEmployee]

A great question. We do have API's for our OEM module customers.  The API is under non-disclosure agreement.   If you want to develop for the SolarBridge API please contact us at SolarBridge or we can take this topic off the forums. 

 

[az1324]

I will always pick the solution with the most open integration capabilities and no requirements to use 3rd party servers/cloud (Enphase API). Closed APIs and software patents just highlight people that think they are too cool for school (they're not). Unsupported APIs are A-OK with me.

I am open to micro inverters but so far am favoring a string inverter such as SMA who have an open API/serial interface.

 

[kwilcox]

That is a problem with enphase envoy. I also have very little use for cloud only solutions.

 

[StewartScottRogers]

After reading the posts I wanted to confirm the SolarBridge Employees statements in summary
 
"SolarBridge uses Power Line Carrier (PLC) system with Frequency Modulation (FSK) at 110 KHz"
 
I am asking this because I want to Bridge or Couple between two different side-by-side townhouses for the sake of using only one monitoring station for both homes. The BenQ panels from both townhouses literally touch end-to-end. All I need to do is couple the signal between solar panel insulations with a short physical hop from SolarBridge connector-to-connector. Obviously electrical codes would not let me just plug them together even if I matched the phases. 

 

[SolarbridgeEmployee]

Hello,
 
There is a possibility that a single power manager could work with both sites if they are as close electrically as you think.  The PLC signal will travel through electrically adjacent houses.  That is why the microinverters are paired with a power manager after discovery to prevent problems with adjacent houses.  When you discover, the power manager will look for all the microinverters that reply and are not assigned to a another power manager.  So if the install is fresh with no microinverters assigned it might discover them all.
 
If you have a power manager onsite with part of the array discovered try and discover the fresh microinverters and see if they add.
 
Of course it will look like one large site and it will not be possible have separate graphs.  But you can look and check for problems and production manually using LTE for each panel.

 

[DonaldPadmore]

I am looking at installing solar panels with SolarBridge microinverters on my garage.   These microinverters communicate their generating status to a central controller using Power Line Carrier (PLC) technology.   UPB modules also communicate vs. PLC.  
 
Does anybody have experience with these systems working in the same house.   Do they conflict?   If they do, is there a way to isolate/filter the signal so that the two systems do not conflict with each other?

Hello friend bit old thread but have you got the system? Even I would love to get similar solar power system so can you give me your true opinion..

 

[kurtmccaslin]

I am ready to move ahead, but am still waiting on some additional info from the electrical utility on rebates.    Rebates are a complex process, but they do make the economics look much better.     I am confident that I will install my 10 KW system, but it will probably take a few months longer than I had expected.

 

[tmbrown97]

I am ready to move ahead, but am still waiting on some additional info from the electrical utility on rebates.    Rebates are a complex process, but they do make the economics look much better.     I am confident that I will install my 10 KW system, but it will probably take a few months longer than I had expected.

 
I plan to start one just after the first of the year - we're shooting for 12.5kw.  Should make a big dent in our utility bills, increase the value of the home, and give us a nice tax break. It's too bad the local utility has run out of money for solar incentives (shocking - considering they're the most expensive utility in the US I think!)... otherwise that would've been another nice chunk.