Victron MPPT EMC issues

[team karst]

I have a couple of the 100/30 units aboard. When active with solar, each unit creates significant rf noise in the 100 to 200 MHz area. This is affecting AIS, reducing receive range from near 20 miles to around 4nm. Also, an airband radio requires almost full squelch to silence.
I will do vhf marine Comm channel testing next. Very likely there will be some impact.
Victron claims emc compliance to a R10 emission spec, which i find odd, since that is a wheeled vehicle standard. In any case, Victron does not want to share the emc test report and said to return the units if not satisfied. Being a retired emc engineer, my plan is to design a solution. Parts are on the way

In the meantime, I would like to know if others also experience this issue and want to trade notes.

[tanglewood]

Originally Posted by team karst

I have a couple of the 100/30 units aboard. When active with solar, each unit creates significant rf noise in the 100 to 200 MHz area. This is affecting AIS, reducing receive range from near 20 miles to around 4nm. Also, an airband radio requires almost full squelch to silence.
I will do vhf marine Comm channel testing next. Very likely there will be some impact.
Victron claims emc compliance to a R10 emission spec, which i find odd, since that is a wheeled vehicle standard. In any case, Victron does not want to share the emc test report and said to return the units if not satisfied. Being a retired emc engineer, my plan is to design a solution. Parts are on the way

In the meantime, I would like to know if others also experience this issue and want to trade notes.

I'm not sure I have anything to contribute, but I'm very interested to follow along with what you find and how you mitigate it.


How did you measure the noise? Is it radiated directly from the MPPT, or conducted? I have the 100/20 model - 4 of them, one per panel. I have noticed that this boat doesn't have as good AIS or VHF reception as my last boat, and perhaps this is why?


Is there anything I can measure with a scope? I happen to have one on board. Or do you think the best testing is to just turn them off and see what happens.


Thanks for bringing this up.

[rslifkin]

I've never noticed anything obvious from my pair of 100/30s, but they're 10+ feet from the nearest VHF or antenna, with the MPPTs being mounted lower in the boat and further forward. I do occasionally question if my VHF reception is as good as it should be (weak signals easily become unreadable static), but I can't say it's bad.

I do remember turning them off at one point (at night, so no input to the panels) and not noticing a difference in where I could have the VHF squelch set. I also took a handheld away from the boat, set the squelch just above the noise threshold and then brought it back onboars. I got it right next to the MPPTs without breaking squelch while they were under some load. But that's not a definitive test.

[team karst]

The AIS test is pretty easy. Kill solar with a blanket or disconnect switches. Find a target reporting 15 to 20 mile range. Reactivate solar charging. Say, 5 Amps minimum. Study the long range target; does it refresh or does it drop out in a couple minutes? Mine will vanish in a few minutes.

VHF comm test: Kill solar. Find a weak NOAA broadcaster. Reactivate solar. Is NOAA still there?
The vhf fm squelch test is not as effective. On channel noise tends to keep fm squelch active.

[Wotname]

Also, an airband radio requires almost full squelch to silence.

Was this with a hand held tx/rx or with an fixed antenna?
At what distance from the MPPT?

Have you noticed any RFI on HF?

[team karst]

Originally Posted by Wotname

Was this with a hand held tx/rx or with an fixed antenna?

At what distance from the MPPT?



Have you noticed any RFI on HF?

No rfi on hf, but i have not looked on 10 meters. Something to do for tomorrow. Icom IC-A110 on the airband. It has a calibrated squelch. Being AM, its squelch design is much different than a fm radio. 10’ approx distance antennas to mppt.
There is one person, on the victron community page that took a spectrum analyzer scan of these mppt’s. Very strong 30MHz fundamental emission. But scan stopped there. But signals at 60, 90, 120, 150 +\- likely.

[SailingHarmonie]

An MPPT 100/50 has no noticable effect at all on our comms. Since we are a MarineTraffic reporting station we have a LOT of statistics about our AIS message traffic that most people do not see. There is no consistent diurnal variation in the AIS reporting range or number of contacts that could be explained by activity in the solar panels.

The only change is that we very occasionally get an extreme range message (100+ NM) in the early morning hours that we have never seen during daylight.

Just another data point...

[Wotname]

Originally Posted by team karst

No rfi on hf, but i have not looked on 10 meters. Something to do for tomorrow. Icom IC-A110 on the airband. It has a calibrated squelch. Being AM, its squelch design is much different than a fm radio. 10’ approx distance antennas to mppt.
There is one person, on the victron community page that took a spectrum analyzer scan of these mppt’s. Very strong 30MHz fundamental emission. But scan stopped there. But signals at 60, 90, 120, 150 +\- likely.

Thanks for the info.
The IC-A110 makes a for great shade tree RFI detector, at least within it's band

[team karst]

Originally Posted by SailingHarmonie

An MPPT 100/50 has no noticable effect at all on our comms. ….
Just another data point...

Good input. About how much distance from mppt and ais antenna?

Using a splitter and masthead antenna?

[GILow]

I've got two of the Victron 100/30s and I installed them in part because they produce so little RF noise.

I think there's something amiss with your AIS installation.

[tanglewood]

So you believe this is all radiated from the device, rather than conducted out through the various wires connected to the device?

[Opie91]

The Victron MMPT controllers do put out a bit of RFI and will kill the VHF reception. Went through that about 5 years back. The Victron tech guy denied it but then did admit it can cause problems.


Put some chokes on it and it did get better but there is always a hit to the VHF and AIS with solar going.

[team karst]

Originally Posted by tanglewood

So you believe this is all radiated from the device, rather than conducted out through the various wires connected to the device?

A lab will test conducted emissions to 30MHz. And then scan radiated emissions starting at 30MHz ending at 2.7 or even 6GHz. So a VHF problem should be caught in the radiated chamber. A good tester will include a length of typical wires to make some attempt at real world conditions. My plan of attack here is to use some 30 A rated external line filters.
The noise is reduced by several ferrite filters, but not enough.
Fixing direct pcb radiation is difficult for a non-owner of the design. It is certainly possible that a good solution would be invasive.

[donradcliffe]

From the design guide of the TIDA 010042 MPPT controller.

Usage of small sized components is made possible by the high operating frequency (up to 200kHz per stage) of the buck converter

[team karst]

Originally Posted by donradcliffe

From the design guide of the TIDA 010042 MPPT controller.

Usage of small sized components is made possible by the high operating frequency (up to 200kHz per stage) of the buck converter

Yes. It makes the flyback inductor and filter caps much smaller. But, it also puts higher freq emissions out there without careful design.