We knew Enphase Envoy and Inverters are communicating using Power Line Carrier,


The Envoy IQ is using Line-to-Line Singal instead Envoy-S's Line-to-N/G Signal.


It is a huge difference, because Envoy IQ is generating Differential mode signal

and, OLD Envoy is generating Common mode signal


To filter the signal from my neighborhood (he has installed Solar System last summer, unfotunately, he & I under the same utility tranformer). To solve the cross domain traffic issue, I need to filter the differential mode signal.


I have installed RP230-30-10-S between IQ combiner busbar And Wire_to_load_center.

It is suggested for Envoy-S (Line-to-N/G) system. but, Double stage filter has a good filtering on DM signal. Especially, this model shows 60dB insertion loss on DM. so, I have expected, it will filter the signal.


Insertion Loss (dB) = 20 * log10 ( Unfiltered / Filtered)

60dB means, 20 * 3 = 1000/1, the signal should be filtered by 1/1000 at 150kHz

Even consider some decay at 100kHz, the filtering performance should be 1/100 or better.

Leakage current of this filter is 1.8mA, it is pretty high loss






but, envoy is showing ‘Communications from other Envoy(s) have been detected’ early morning. And it is disappearing till evening, and showing again.


I have installed GTX-2300-Y02 between Wire_from_envoy and Breaker_Load_Center


Insersion loss is around 20dB in common mode. there is no differential value.

I am expecting around 10dB minimum, but, the leakage current is 0.5mA,

Too expensive to use it,






Load center and combiner has located as below




MI - Combiner - RP230 - GTX2300 - Critical Load Center - XW 6848 - Main Load Center - Grid


Unfutunately, it can not solve the issue,

the message come again and again ~ like a die hard ....


Wait a minitue, just thinking again,


Common mode signal.JPG


New Envoy is Line-to-Line communication, so, I have to remove/block a differential mode signal,

it means, the common mode filter is not working.


  • Envoy-S    same as Common Mode Signal
  • Envoy-IQ   same as Differential Signal


If install Ferrite Core on L1/L2, yes, it should not working -.-, that is just for old Enovy ONLY. !!!!


GTX-2300, it is a typical single stage common filter, it is good on common noise, and, have some filter for differential mode noise, i feel, that is not strong enough.




and, RP230-30-10, It is double stage filter, it have 60dB insertion loss on DM at 150kHz.



Unfotunately, those filters can not block the signal and, my envoy still detect the other Envoy(s). 



BUT, I feel so strange,


(1) it is detected when early morning  - when MIs start to work

(2) it is detected when evening - when MIs stop to work

(3) sometime at evening


so, I have tried to check the noise level and filtering level using SA




it makes me so disappointed, because I can not detect any signal from outside for couple of hours.

I have checked my device again, turn-on Enovy and check the signal




My equiment can detect a communication signal which has been generating from my Envoy.

I can find a signal, and confirm the filtering even I can not find the exact level of filtering.




How my Envoy detect the other Envoy(s) signal ?

How my Envoy detect the other Envoy(s) signal after 2 filters ? there is 60dB insertion loss. Is it possible to be detected ?


ANYWAY, most power line filter is designed to minimize the power loss using small capacitor.

It means, not strong enogh on DM filtering, BUT, can not explain the the message while low power mode. Because filter will lost the performance while higher current mode,


I have ordered Q-LCF-064-1P-1 to make sure,


Because it said, IQ compatible,


75W maximum loss (via the maximum current), should be under 1/16 at my appliaction.

anyway, around ~19Wh is so high power consumption 


75W x 1/16 & 4.15h = 19Wh per day (or 7.1kWh per year)

Maybe need to try for the DM mode noise