question

schan avatar image
schan asked

reverse battery polarity connection - Smartsolar 100/30

I accidentally reversed the battery polarity connection to the SmartSolar 100/30. Now the MPPT blue light kept blinking but no charging took place. The unit can still communicate via bluetooth.

What possible went wrong? Is there an internal fuse that I can replace to recover the unit?

I appreciate any help. Thank you.


MPPT Controllersbattery charging
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4 Answers
wkirby avatar image
wkirby answered ·

There is a non-replacable fuse inside. Contact your distributor and see what they can do for you.
In reverse battery polarity conditions, the active components will short circuit long before a fuse has a chance to react. The fuse is to prevent current from flowing through damaged components and making a fire.

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schan avatar image schan commented ·

The charger was bought in July 2019. I contacted the seller but was told it's still under warranty but declines to get help. I checked Victron's warranty policy and that the reverse battery polarity would not cover. I would expect such basic protection feature should have been provided in the charger, unfortunately it's not the case. In fact, other vendors' MPPT do provide such reverse polarity protection. Now the charger becomes trash. What a waste!

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mvader (Victron Energy) avatar image mvader (Victron Energy) ♦♦ schan commented ·

Hi @SChan, sorry to hear about the broken charger!

Please ask your dealer to lodge it to us as an RMA. Indeed our formal wording denies reverse polarity claims; but where possible we are easy and helpful with warranty and/or can help with a discounted unit sometimes. Note that I cant promise whats going to happen in this case; but please do make sure the unit is lodged to repair. (RMA).

With regards to such basic protection to be in the charger or not: it can be done, but adds cost, and we believe that its better to not increase the cost of all units by adding such protection.

Ps: since the light is still blinking and such; do go through basic troubleshooting (for example fuses and pv array voltage) to make sure its really broken.

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schan avatar image schan mvader (Victron Energy) ♦♦ commented ·

Hi mvader, thanks for the suggestions. I emailed the seller again yesterday and told them to lodge it as an RMA but so far have not heard from them yet. Their response was not good at all ever since I started to contact them a week ago.

I wonder if I can lodge an RMA directly to Victron as I have the invoice and the serial number etc. to verify I'm the owner of the charger? That would be a great service to the customers if Victron can handle it directly.

I checked again today the MPPT, the solar panel and the connections to make sure all are connected probably, The MPPT could communicate with my phone via the Victron app yet no charging took place while the solar panel and others were working probably. The charger is clearly not working as it should be.

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coltarkdm avatar image
coltarkdm answered ·

I did the same thing but my controller (same as your's) is working fine. How did you determine it isn't working other than the blinking blue light? Victron Connect app?

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schan avatar image schan commented ·

The MPPT could communicate with my phone via the Victron app yet no charging took place while the solar panel and others were working probably. The charger is clearly not working as it should be.

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Justin Cook avatar image
Justin Cook answered ·

@SChan, have you checked all the associated fuses/breakers on the system? Outside of the charger itself, I mean. Reversing polarity at the charger could have easily blown the fuse on the line between the charger and battery, or the charger and PV panels either one... worth an inspection if you haven't already, particularly if your dealer is being difficult.

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schan avatar image schan commented ·

Fortunately both the 400W solar panels and the LiFePO4 cells can survive the stock, except my 1500W pure sine wave inverter and the Victron MPPT. Luckily enough, the inverter can be recovered by replacing the blown out fuses. Now I'm running on an 20A MPPT solar charger of other brand which has the reverse battery polarity protection.

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Justin Cook avatar image Justin Cook ♦♦ schan commented ·

@SChan, I was more wondering if -assuming that you have the line from the charge controller to the battery fused- the fuse between charge controller and battery had popped, thus why your charge controller isn't charging.

You mentioned that the charger is still communicating with VC, which means (to my mind) that the internal fuse hasn't blown, which indicates to me that perhaps the controller is still okay, it's just not charging because the fuse at the battery that protects the controller to battery wiring is blown.

Again, that's assuming that you have a fuse at the battery that's protecting that wiring - it should be a ~40A fuse or circuit breaker on the POS lead from the "battery" output of the controller, and likely located very near the battery.

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zorbakalimero avatar image
zorbakalimero answered ·

I did the same thing. and after at the Victron Connect app always float . i am very unhappy and afraid about broken the my smartsolar and mine is 100 / 20, because i buyed only 3 day ago and firts time i make a connections .


and than i chechked the fuse and yeahh fuse is damaged. when i change 25 amper fuse it is working great again.

everything happened today before check the fuse, i finded this conversation.and when i find the solution i want to share with everybody. sorry about my less english.


and if you want, you can follow me on youtube, i will show everything about this

https://youtu.be/4gaCqaKAnmM with the video.

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