Victron MPPT EMC issues

[tanglewood]

Originally Posted by team karst

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.

OK, so unknown at this point where the noise is getting out.

[Karanga]

Just another data point...
My VHF masthead cable runs under the saloon seats, within 6 inches of a 150/85 victron controller, a victron 3000/120 inverter, a victron 100/50 controller and 2 victron 100/30 controllers.
The actual VHF and AIS (and splitter) units are approximately 10 feet away from all of these.
I have noticed no (zero, nada) difference in reception in day or night operations, bulk DC charging or bulk AC loads.
So I don't think I have any emf effects from my victron hardware.
I do notice a significant (more than 50%) decrease in VHF (AIS) performance when my anchor light is on. Unfortunately this light has an integral non-replaceable LED bulb.

[Gypsy23]

This thread prompted me to do some testing today. I have a Victron SmartSolar 100/20 regulator circa 2109.


Over the past year I have been chasing radio interference on one part of our sailing club’s radio comms which uses an old HF CB 27MHz band – AM. Old and limited but useful for the club as the VHF band is crowded but there are few users on 27MHz. I have used various spectrum analyser methods but the most useful has been a USB software controlled radio module (SDR) which has an app (Air-Spy) to display up to 2MHz bandwidth as a real-time spectrum with precise frequency markers and relative signal levels in db across a wide frequency range. I have used this in the past also to inspect the general Marine VHF band and AIS activity in particular.


My boat is a 11.3m (37ft) single mast sailboat with a 17m mast at the head of which is a 90cm VHF whip antenna shared through a B&G NSPL400 splitter. The SDR was patched to the AIS feed of the splitter in place of the AIS transceiver. The tests were done at my mooring in the upper reaches of Sydney Harbour (AU) where there is significant AIS activity from commercial and private vessels, typically more than 50 targets within range. I have a single 300W solar panel fed via 10m of cable to a Victron 100/20 which is mounted approx 50cm below the power management panel. The splitter and AIS are behind the power panel.


Test Results:

1. Most observations were focused on AIS channels 161.975 (Ch87b) and 162.025 (Ch88b).
2. AIS signals were received on both 87b and 88b at levels ranging from -35db to -50db.
3. The base noise level with fridge and VHF radio on was -62db.
4. The noise level did not change when additional nav instruments and a Zeus 2 plotter were switched on.
5. When 4 LED internal lights were added the noise level lifted by approx 1db, but no evident spikes of RF.
6. The Victron was supplying 8-9A at 12.8V.
7. When the solar panel was fully covered and the Victron supplied no charge current, there was NO change to the noise level.
8. LED Nav lights, bow x2 and stern x1, were switched on with NO addition to noise.
9. When the LED Steaming light was added it produced spikes of RF interference at -55db to -50db gradually drifting across the 400KHz displayed. Later this was also seen across 2MHz of the band when centred on 156.800MHz (Ch16). This could be heard on the SDR# app but it did not break the squelch on my VHF. No doubt I could have reduced the squelch and heard it on my VHF.
10. With the nav/steaming lights off, the LED deck light was added. It raised the base noise level from -62db to -50db across the 400kHz AIS part of the band but did not trigger the VHF squelch. AIS signals were still seen but we can expect that more distant targets could/would be swamped by this interference.
11. The Steaming/Deck light is a combined unit fitted to the face of the mast. I don’t know the brand of light, I’ll have to climb the mast to check.

Conclusion:
My Victron 100/20 is not creating interference in the VHF/AIS band...BUT...I do have a problem with the Steaming/Deck light. The Deck light is worst but I do not usually have it on when under way. The Steaming light has minor spikes which have variable effect, but it is not a blanket interference across one or more channels. The problem is how to find a replacement which doesn’t create interference? Replacing it is not a trivial exercise in either cost or practical effort.

[Karanga]

Originally Posted by Gypsy23

This thread prompted me to do some testing today. I have a Victron SmartSolar 100/20 regulator circa 2109.


Over the past year I have been chasing radio interference on one part of our sailing club’s radio comms which uses an old HF CB 27MHz band – AM. Old and limited but useful for the club as the VHF band is crowded but there are few users on 27MHz. I have used various spectrum analyser methods but the most useful has been a USB software controlled radio module (SDR) which has an app (Air-Spy) to display up to 2MHz bandwidth as a real-time spectrum with precise frequency markers and relative signal levels in db across a wide frequency range. I have used this in the past also to inspect the general Marine VHF band and AIS activity in particular.


My boat is a 11.3m (37ft) single mast sailboat with a 17m mast at the head of which is a 90cm VHF whip antenna shared through a B&G NSPL400 splitter. The SDR was patched to the AIS feed of the splitter in place of the AIS transceiver. The tests were done at my mooring in the upper reaches of Sydney Harbour (AU) where there is significant AIS activity from commercial and private vessels, typically more than 50 targets within range. I have a single 300W solar panel fed via 10m of cable to a Victron 100/20 which is mounted approx 50cm below the power management panel. The splitter and AIS are behind the power panel.


Test Results:

1. Most observations were focused on AIS channels 161.975 (Ch87b) and 162.025 (Ch88b).
2. AIS signals were received on both 87b and 88b at levels ranging from -35db to -50db.
3. The base noise level with fridge and VHF radio on was -62db.
4. The noise level did not change when additional nav instruments and a Zeus 2 plotter were switched on.
5. When 4 LED internal lights were added the noise level lifted by approx 1db, but no evident spikes of RF.
6. The Victron was supplying 8-9A at 12.8V.
7. When the solar panel was fully covered and the Victron supplied no charge current, there was NO change to the noise level.
8. LED Nav lights, bow x2 and stern x1, were switched on with NO addition to noise.
9. When the LED Steaming light was added it produced spikes of RF interference at -55db to -50db gradually drifting across the 400KHz displayed. Later this was also seen across 2MHz of the band when centred on 156.800MHz (Ch16). This could be heard on the SDR# app but it did not break the squelch on my VHF. No doubt I could have reduced the squelch and heard it on my VHF.
10. With the nav/steaming lights off, the LED deck light was added. It raised the base noise level from -62db to -50db across the 400kHz AIS part of the band but did not trigger the VHF squelch. AIS signals were still seen but we can expect that more distant targets could/would be swamped by this interference.
11. The Steaming/Deck light is a combined unit fitted to the face of the mast. I don’t know the brand of light, I’ll have to climb the mast to check.

Conclusion:
My Victron 100/20 is not creating interference in the VHF/AIS band...BUT...I do have a problem with the Steaming/Deck light. The Deck light is worst but I do not usually have it on when under way. The Steaming light has minor spikes which have variable effect, but it is not a blanket interference across one or more channels. The problem is how to find a replacement which doesn’t create interference? Replacing it is not a trivial exercise in either cost or practical effort.

I enjoyed your research and results.
I found it very useful to talk to the guy at
https://www.ledshoponline.com.au/shop/
He supplied me with better 12v only LED bulbs (vs 9-30v noisy LEDs)

[Gypsy23]

Thanks for your comments and the the link, Karanga. I know of them but haven't looked at their range recently. It is a wide range these days! Yes, I guess 12V specific LED's are probably better behaved without the need for DC-DC converters to handle low to high voltage boosts.
I think my biggest problem will be that the LED's in the combo Steam/Deck light are likely to be fixed rather than replaceable. But I'll take a good look when I go up the mast some time in the next few weeks.

[Karanga]

Originally Posted by Gypsy23

Thanks for your comments and the the link, Karanga. I know of them but haven't looked at their range recently. It is a wide range these days! Yes, I guess 12V specific LED's are probably better behaved without the need for DC-DC converters to handle low to high voltage boosts.
I think my biggest problem will be that the LED's in the combo Steam/Deck light are likely to be fixed rather than replaceable. But I'll take a good look when I go up the mast some time in the next few weeks.

I have downloaded the SDR app etc. Now I need to find some suitable hardware.
It all sounds so much more sophisticated than the blunt and often unproductive VSWR meter

[Gypsy23]

Oh yes, much more sophisticated and useful. It takes time to get used to but a neat gadget. Not so many years ago you have needed $50k or more for an instrument to do this.
Search on-line for RTL-SDR. Probably about $50-70.

[team karst]

Originally Posted by Gypsy23

Thanks for your comments and the the link, Karanga. I know of them but haven't looked at their range recently. It is a wide range these days! Yes, I guess 12V specific LED's are probably better behaved without the need for DC-DC converters to handle low to high voltage boosts.
I think my biggest problem will be that the LED's in the combo Steam/Deck light are likely to be fixed rather than replaceable. But I'll take a good look when I go up the mast some time in the next few weeks.

Mix 61 ferrite placed on the cable close to the lamp should have a positive effect.
Also, breaking squelch is not a reliable indicator for interference. Better to listen to a weak signal for any effect.

[Gypsy23]

Originally Posted by team karst

Mix 61 ferrite placed on the cable close to the lamp should have a positive effect.
Also, breaking squelch is not a reliable indicator for interference. Better to listen to a weak signal for any effect.

Tks Karst. I may try a ferrite but access is tricky. Hopefully I can replace the lamps so stop the problem at the source.


I agree that squelch is not a good indicator/test. It was just a comment that the interference I could see on the spectrum screen was not so strong as to interfere with how I usually had my squelch set. It also tells me that any valid/weak signal of that level would not have broken my squelch either.


BTW, the signal levels I used in my test notes are db relative to full scale on the analyser screen, not absolute dbm. The internal gain I was using for those measurements was 20db so the actual floor level of noise was more like -82dbm. It is not a calibrated instrument so I am cautious of stating absolutes but it is a wonderful tool for visualising what we may hear on the radios.

[team karst]

I do need to invest in a small portable spectrum analyzer with some close field probes. Part of my conversion from corporate stiff to independent. [emoji106]

[Gypsy23]

Originally Posted by team karst

I do need to invest in a small portable spectrum analyzer with some close field probes. Part of my conversion from corporate stiff to independent. [emoji106]

I have used close field probes with the SDR, cheap ones from China. I don't have a good way of calibrating the results but they are yet another 'tool' to help understand what is really happening on a PCB or other electronic device.

[K1MGY]

I plan to drag my spectrum analyzer aboard and do some testing, as I have various LED lights. Especially troubling is the Vesper Cortex (AIS and a bunch of other neat features), where the Cortex VHF sensitivity is far below (subjective measurement) of the attached Icom marine VHF (same antenna - the Cortex supports a second radio). Wondering now if this sensitivity difference is inherent in the Cortex front end or caused by interference that doesn't bother the Icom radio...

Regarding the LED's, has anyone tried ferrite cores at the LED end?

[Kolchac]

Simple physics:
100/30 is designed for a series connection of panels. Using it for one panel is a mistake (if you use 18 V for 12V).
Connecting panels in series increases the voltage (like 18V + 18 V = 36 V), but the amount of current would be the same as from one panel.
To convert extra voltage to extra current they use an electrical transformer (it is not innovation!). The transformers work only with AC. So they convert high voltage DC(36V) to high voltage AC(36V), then, using the electrical transformer, they transform high voltage AC(36) to low voltage AC(12V), then convert AC(12) to DC(12V).
Using these three transforms they lose ~30% of power theoretically, and practically more. The size of the electrical transformer depends on AC frequency - higher frequency - smaller size. So they use probably approximately 100 KHz transformer.
So why do you see 100-200 MHz? Because instead of generating sinusoidal AC, they use square pulses, which have a lot of high-frequency harmonics.
As an emc engineer, you should understand, that this HF emission 90% goes through the wire, not by air through the box. So even the battery cannot suppress it. You cannot do anything with that.
The solution is simple:
Use parallel connection of the panels, and use a $20 controller (which has the same Taiwan microchips as a $300 one), which does not have any transformers.
If you have a sun shade problem (for what Vicron offers this design), much better to use several small panels instead of a big one.

[stgermain45]

Quick data point: We have 3x 100/30 Victron controllers. No issues observed on VHF/AIS (that I know of), but our HF SSB is essentially unusable during daytime hours if we don't turn off the solar controllers. This is with multiple Ferrite chokes and a single core 1:1 isolation Balun (1.5-54 Mhz, 3kW) installed on the feedline.

[team karst]

Originally Posted by stgermain45

Quick data point: We have 3x 100/30 Victron controllers. No issues observed on VHF/AIS (that I know of), but our HF SSB is essentially unusable during daytime hours if we don't turn off the solar controllers. This is with multiple Ferrite chokes and a single core 1:1 isolation Balun (1.5-54 Mhz, 3kW) installed on the feedline.

Interesting. Is the AIS/VHF at masthead? I see more of the hf issue at 10M. 40M no effect, although the atmospheric qrm has been bad lately.