smueff1970 avatar image
smueff1970 asked

MPPT RS 450/100 Error 201 each morning (FzSonick)


each morning my 3 MPPT RS shows in the display



I switching the power switch on the 3 mppt rs off and on and it will be working. on the next moring the same problem.

the resistors R207, R208 looks good.


1 MegOhms, 1%, Metalfilm

At the moment the voltage on my salt batteries (FZsonick) are low and all devices are off in the night.

Please help.



mppt rs
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1 Answer
Thiemo van Engelen (Victron Energy staff) avatar image
Thiemo van Engelen (Victron Energy staff) answered ·


What are the firmware versions of the MPPTs?

Did you connect with the latest VictronConnect and update the firmware to the latest version? Or perhaps update to the latest version via VRM when it is connected to the VRM website?

Kind regards,

Thiemo van Engelen

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smueff1970 avatar image smueff1970 commented ·

Hi Thiemo,

thanks for your answer.

MPPT RS have also the latest version 1.05 and Venus 2.73.

VRM is not possible, i have no internet connection and no electrical connection to the public powerhouse. its an island solution.

it seems the problem is on the 48V DC site, not on the PV site.

i found when the batteries are in "warm up mode" only the problem exists. if the batteries are warm and charged on the next moring i have ~ 51 V DC on the 48 V DC Site and no error comes up.

if the batteries are discharged and and the power is less to keep them warm up on the next morning the 48 V DC Bus is "off". Then the error appears again.

On Morning one of the 3 MPPT RS had no error. i switched off and on the other 2 with the 201 error and they are woring. but some seconds later the on who had no error on this moring got than the 201 error and i had also off/on the device.

My idea:

When the 48V DC Bus is "off", also the Venus is off. Than on the moring the power from the solar panels comes up. The trackers start to work, but the VE.Bus is off because the Venus is now starting booting (they is connected also to the 48V DC Bus for the power input). Than the MPPT RS will not speak to each other and i had the DC Voltage Error 201.

Perhaps in can be es solution only one MPPT RS switch to on. and the others switch on if the venus is up and VE.Can is working. I don't know if that would help.


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mvader (Victron Energy) avatar image mvader (Victron Energy) ♦♦ smueff1970 commented ·
Hello @smueff1970 , we looked at this, and its related to the FzSonick Salt batteries having an internal DCDC converter, in between the Salt cells and the battery terminals.

We're working on a fix; it can take a few more weeks.

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