MPPT creates RFI interference affects AIS

[Jack C]

Does anyone have a solution for RFI interference caused by MPPT controllers.

I get an AIS signal signal error whenever the MPPT controller is running.

I moved the AIS unit away from the MPPT controller but it did not help.

The AIS antenna is close to the solar panels so perhaps they are acting as a noise antenna.

I plan to test with the radio antenna at the top of the mast to eliminate the current AIS antenna and its location as the problem.

It appears that MPPT controllers are NOT required to have FCC certification. (Lobbying by the solar industry?)

[seandepagnier]

why would the mppt be required to be certified? If you dont like dont buy that one, it's wrong to require something that not everyone even cares about. Or should government require all furling gears have independent tack swivel?

Try:

* override switch (bypass) to use for dirct charge when you need ais
* beads, ferrites etc. Filter the power
* eventually, even use dc-dc isolated power supply to power ais

[Jack C]

Originally Posted by seandepagnier

why would the mppt be required to be certified? If you dont like dont buy that one, it's wrong to require something that not everyone even cares about. Or should government require all furling gears have independent tack swivel?

Try:

* override switch (bypass) to use for dirct charge when you need ais
* beads, ferrites etc. Filter the power
* eventually, even use dc-dc isolated power supply to power ais

All MPPT controllers including Victron generate RFI. FCC regulations are to protect the public from RFI interference created by electronic devices.

For instance your devices such as cell phone TV etc. Being affected by your neighbors devices.

With respect to boating, the RFI noise can affect you hearing a Mayday on VHF or SSB.

While sailing when you need solar power unless you rely on a generator or engine


So no AIS, no reliable VHF and possibly missing a distress call while the MPPT is working.

All this to help the solar industry and increase manufacturers profits.

Unfortunately your suggestions will not help.

The MPPT controller is creating airborne RFI, so a separate power supply for AIS will not help.

Perhaps a ham radio operator can make suggestions?

[noelex 77]

Originally Posted by Jack C

I get an AIS signal signal error whenever the MPPT controller is running.

What model is your controller?

[Jack C]

I have 3 boats, 3 different manufacturers. One is Renology, another is a Chinese brand , can't remember right now, the third is a small outfit in the USA.

An internal search found a Victron forum where the problem is well known.

All use MOSFETS for high speed chopping which creates the RFI.

[noelex 77]

So if understand correctly you have three boats with three different brands of controllers and in each case there is an AIS signal error when the solar controller is powered on.

Is this correct?

[GordMay]

Solar System RFI
The Problem, and the Solutions
➥ https://palomar-engineers.com/rfi-kits/solar-system-rfi

FWIW:

”... All solar components should carry a FCC certification of Part A for commercial installations or Part B for residential installations.

Note that devices certified for type A only WILL cause RFI under 30 MHz and these devices should be avoided in residential installations.

Devices without FCC certification should also be avoided – these devices are quite common on popular internet auction sites that sell goods direct from overseas locations not required [by THEIR AHJ] to have FCC certification and testing ...”

[Jammer]

Twist the wires from the MPPT to the panels if possible. 3 twists per foot. That will get rid of most of it. Most of the noise is differential mode and twisting the wire makes it ineffective as an antenna. The MPPT controller itself doesn't radiate much, it's the wires you attach to it that give it an "antenna" that make things bad.



Put ferrite beads on the wires from the MPPT to the panels.


Put ferrite beads on the wires from the MPPT to the battery bus.


Put ferrite beads on the coax to the antenna. I would start by putting them close to the antenna but you can try close to the AIS. They will have the effect of making the coax pick up less noise where it is close to the solar wiring, and will concentrate the sensitivity in the antenna itself.

[tanglewood]

There seem to be lots of assumptions about what device is generating RFI (asserted to be the MPPT controller), whether it's radiated or conducted, and whether that's the cause of AIS issues.


Is more info available on what's behind the assertions/assumptions?


It's true that any switching electronics (includes MPPT controllers) will generate RF, but it's the designers job to contain it to acceptable levels. "Acceptable" in the US is at least FCC Part 15, A or B. It's illegal to sell a device in the US that doesn't comply, but that doesn't stop a huge amount of cheap junk flooding into the US market.


I'd be very interested to hear why MPPT controllers are exempt from FCC Part 15? That would be a big surprise to me.

[Emmalina]

I found PWM controllers to cause more than mppt controllers and some of the cheap Chinese made controllers claiming to be mppt are actually pwm What make are these things ?