Interference with receiving Radio Stations

[mdtcoll]

I had a Solar System installed last May, 2012. Since then, I have not been able to receive any radio stations clearly. Has anyone else had this problem? If so, is there anything that can be done like adding a filter on the radio receiver or something?
David

[TomP]

I had a Solar System installed last May, 2012. Since then, I have not been able to receive any radio stations clearly. Has anyone else had this problem? If so, is there anything that can be done like adding a filter on the radio receiver or something?
David

Odd, what kind of lighting are you using?
I have been meaning to post on my camera forum a similar problem with my TV. I have one channel that is severally affected by electronic lights. If I want to watch channel 29, I have to turn off 2 LED lights and one Max Vision true color florescent light. My home is of an old design and we still use a few electronic 12V RV lights that use an TF8 bulb, these do not cause any problem. At times I have suspected my wireless of causing a minor flicker with the TV. The TV is a Sony XBR.

[mdtcoll]

[The lighting is standard house lighting. Ie; incandescent bulbs, and some energy saver flourescents. It doesn't matter wether they're on or off. No clear radio reception. Even the car radio goes out when I get into the driveway.
David

[Sunking]

I assume Grid Tied right? Your complaint is very common and expected. The RFI is being generated by your inverter. You need to contact your installation contractor and/or the inverter manufacutre but do not hold your breath waiting for a solution. At least your car radio works when you get away from your house, poor folks in California cannot escape as just about the whole Pacific highway is just one large RFI zone caused from Grid Tied systems.

[bcroe]

Electro Magnetic Interference

EMIfilters.jpg

I assume Grid Tied right? Your complaint is very common and expected. The RFI is being generated by your inverter. You need to contact your installation contractor and/or the inverter manufacutre but do not hold your breath waiting for a solution. At least your car radio works when you get away from your house, poor folks in California cannot escape as just about the whole Pacific highway is just one large RFI zone caused from Grid Tied systems.

There isn't much that can be done about the neighbors' interference. Micro converters would be a problem,
because there are so many & they are located outside. But a big central inverter could be toned down. The
radiation will be coming from some combination of the panel DC input wires, the body of the inverter, or the
AC output wires. A little snooping with a portable radio might indicate the worst point.

EMC filters could be simple capacitors, a simple network, or a multi stage network. These must be rated for
the voltage & current involved, like everything else. I often use off the shelf units like these. However, the
prices of the larger ones go up pretty fast. The filters will need to be in their own electrical boxes for safety,
connected by metal conduit to the inverter, to maintain a radio frequency shield. If there is still leakage (from the inverter case), it may be necessary to build a shield around it using something very well ventilated, like 1/2" grid hardware cloth. Bigger is fine, to allow plenty of airflow. Seams must be carefully sealed, and it needs to be well connected to the filter boxes where the wires enter. Bruce Roe

[FunGas]

The radiation will be coming from some combination of the panel DC input wires, the body of the inverter, or the AC output wires.

I would have said the (circuit in the) body only, maybe a little leakage into the connected cables, but then, I've never had an inverter issue.
Switch mode power supplies are my bane, building a Faraday cage around them as you describe usually dampens the noise enough for H.F. reception, together with chokes/ferrite rings on the output.
Worst case scenario is if the noise is transmitted out down the A.C. lines, but back to the panel should be blocked by diodes? no?

[Sunking]

I would have said the (circuit in the) body only, maybe a little leakage into the connected cables, but then, I've never had an inverter issue.
Switch mode power supplies are my bane, building a Faraday cage around them as you describe usually dampens the noise enough for H.F. reception, together with chokes/ferrite rings on the output.
Worst case scenario is if the noise is transmitted out down the A.C. lines, but back to the panel should be blocked by diodes? no?

Fungas got any more of that Gas you are breathing? Or is it LSD?

[bcroe]

Filter

I would have said the (circuit in the) body only, maybe a little leakage into the connected cables, but then, I've never had an inverter issue.
Switch mode power supplies are my bane, building a Faraday cage around them as you describe usually dampens the noise enough for H.F. reception, together with chokes/ferrite rings on the output.
Worst case scenario is if the noise is transmitted out down the A.C. lines, but back to the panel should be blocked by diodes? no?

My experience is, an inductor alone won't do a lot. Properly rated bypass capacitors can make a big difference. Putting
them together does more. But at that point, instead of reinventing the wheel, I look for a ready made filter. An old 1KW
supply I "modernized" with a switching prereg, needed 2 stages of filters & shielding to be pretty clean.

A conducting diode won't help you at all. Cut off it might stop RF, except you can't do any power that way. Bruce Roe

[DanKegel]

I was happy to see my installer put in chokes on the DC input and AC output lines from my Solar Edge inverter without even being asked to
See pic: https://goo.gl/photos/7UTkPWcLgc252aHq5
I just checked for RF interference and didn't notice much more when the inverter was switched on vs. switched off... it was about 10% more hiss when receiving WWV with the receiver right next to the inverter. But I don't use AM or shortwave radio much, and maybe the results would be worse out in the sticks where the air is much quieter.

[DaveDE2]

I was happy to see my installer put in chokes on the DC input and AC output lines from my Solar Edge inverter without even being asked to
See pic: https://goo.gl/photos/7UTkPWcLgc252aHq5
I just checked for RF interference and didn't notice much more when the inverter was switched on vs. switched off... it was about 10% more hiss when receiving WWV with the receiver right next to the inverter. But I don't use AM or shortwave radio much, and maybe the results would be worse out in the sticks where the air is much quieter.

Did your installer put those in or did they come preinstalled with the inverter?

[sensij]

Did your installer put those in or did they come preinstalled with the inverter?

I have a SolarEdge 3000 W inverter, and it didn't come with anything like that. Looks to me like the installer put them in.... used black (probably UV rated) zipties that would typically be used on the external wiring, not the basic nylon zip ties that were clearly factory installed elsewhere inside the inverter.

[DanKegel]

I checked, and Solar Edge's doc and install video don't show the chokes. Also, they are on the leads attached to the final I/O terminals, so they couldn't have come preinstalled.

Edit: the installer says the chokes are indeed from SolarEdge. (They're in the final I/O terminals... of the top unit, which evidently comes preassembled along with the bottom unit.)

The chokes are pretty massive, too. And I verified that the case of the upper unit is metallic, the door is much heavier than plastic. (The lower unit's case is plastic, but there are no electronics in it.)

[Sunking]

I was happy to see my installer put in chokes on the DC input and AC output lines from my Solar Edge inverter without even being asked to
See pic: [COLOR=#212121][FONT=Roboto][SIZE=14px]https://goo.gl/photos/7UTkPWcLgc252aHq5]

Will not do much of anything to stop RFI as you noted. AM radio and all low frequencies are pretty much history in CA in cities.

Ham radio operators are raising hell with the FCC about Solar wiping out HF bands all up and down the coast. FCC has been told to ignore the complaints by you know who.

--Mod Note: Remember that there are limits on the discussion of politics and, of course, civil discourse, even here in the General Discussion topic.

[bcroe]

As I said, those chokes are only good for several db, not very useful when you need 10 or 20. Fortunately my own
inverters came with pretty good filters, because the radio tower is out in the same area as the panels. Bruce Roe

[inetdog]

As I said, those chokes are only good for several db, not very useful when you need 10 or 20. Fortunately my own
inverters came with pretty good filters, because the radio tower is out in the same area as the panels. Bruce Roe

+1
An interference filter designed for RF and containing a shielded combination of inductors and capacitors will do a much better job. (See Post #5)
You can also tune a filter to do its best job at one particular RF station or band.

Going back to the OP's original question about adding a filter to the radio receiver, that will be useful only if high levels of RF outside the tuned frequency band of the receiver are coming in through the antenna and overloading the input stages. That can happen with a transmitter from another band, but much less likely with broad band interference such as that produced by power electronics.