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AC to DC Power Supply Feeding Victron MPPT Controller

featherlite

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Question: Will feeding power to a Victron MPPT solar Charge controller from an AC to DC power supply damage either: (i) the controller or, (ii) the power supply?

My Components:
1. Meanwell AC to DC variable power supply (13.5v to 18v) maximum rated current 33.4A
2. Victron SmartSolar MPPT 100/50
3. 280A Lifepo4 12v battery

I currently shore charge my batteries by feeding power to a programable Bogart 30A PWM charge controller with the above Meanwell power supply. This saves me from having to buy a separate multi stage shore power charger when solar is not available. Bogart recommends this technique and I have been so doing for quite some time without issue.

Do you think that feeding power to the Victron MPPT solar Charge controller from the Meanwell power supply will damage either: (i) the Victron MPPT controller, or (2) the Meanwell?

If you think that either the Victron MPPT controller, or the Meanwell, will be damaged, how about if I used my 18A Victron Orion-Tr Smart DC-DC Charger (12/12/18) instead of the MPPT controller?

Thanks for your help!
 
The answer is it depends

The mppt action will attempt to load the poser supply to the Maximum current capability of the mppt , in this case 50A ( assuming the battery can accept this power ) hence this will overload the meanwell

If the meansell has current limiting option ,ie foldback or constant current setting and hence it’s drops it’s output voltage as that limit is reached then the mppt action will stop at that current limit point.

Another way to fool the mppt is to add series power resistance of a low value to the output of the meanwell. However at high currents the power dissipation in the resistor is high.

The other way is to use a power supply with greater current capability then the max input capacity of the mppt.

The other is an mppt controller with input configurable current limit The Victron has a “ battery current limit” so this can be reduced to protect the meanwell
 
Thanks Goboatingnow.

The Victron MPPT 100/50 controller manual says:
"The output current of the solar charger is current limited to its rated current."

However, I did not find anything in the manual to indicate that the current drawn by the MPPT controller can be adjusted to limit current below the stated current rating of 50A.

I ordered the Victron MPPT but have not yet received it. Consequently, my knowledge is pretty limited at this stage of my learning curve.

I also ordered a Victron Orion-Tr Smart DC-DC (12/12/18) Charger Isolated so that I can use my truck's alternator to charge my Lifepo4 battery.

Am I correct to assume that I can use the 30A Meanwell power supply to feed the 18A DC-DC charger to charge my Lifepo4 battery without damaging either: (i) the Victron DC-DC charger, or (2) the Meanwell?

Again, help is much appreciated!
 
In the manual, you can set the battery charging current, so you should set it so the MPPT will not be try to draw more than 80% of your power supply current to be safe and for long term operation, so around 25A should be good. Do you have DC Clamp on Amp meter?


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Bud,

Thank you for finding the solution in the MPPT manual, which I missed, and for the advice to set the charger at 80% of the Meanwell's rating!

Yes, I have a DC Clamp on Amp meter, and a battery monitor with a shunt, to measure Ah.

I am very grateful for your help!
 
Question: Will feeding power to a Victron MPPT solar Charge controller from an AC to DC power supply damage either: (i) the controller or, (ii) the power supply?

Do you think that feeding power to the Victron MPPT solar Charge controller from the Meanwell power supply will damage either: (i) the Victron MPPT controller, or (2) the Meanwell?

If you think that either the Victron MPPT controller, or the Meanwell, will be damaged, how about if I used my 18A Victron Orion-Tr Smart DC-DC Charger (12/12/18) instead of the MPPT controller?

Thanks for your help!
Suggest you read section 9.8 Operation Issues in your manual.....

Mine is a different model so section number may differ and your results may differ
 
Tecnodave,

Thanks for pointing that section out.

The MPPT manual says:

"9.8.2. Unable to operate as a DC to DC charger
It is not recommended to use the solar charger as a DC/DC charger, for example, to charge a 12 Volt battery from a 24V battery
bank.
Connecting a battery to the PV terminals can, under certain operational conditions, cause damage to the solar charger. This damage is not covered by warranty."


The above section from the manual is what prompted me to ask my original question. I wonder what those "certain operational conditions" are that can cause damage and why.

Also, I wonder what the difference is between using a solar array vs. using a power supply to feed the MPPT.
 
I wonder what the 'under certain operational conditions' really means.
The Solar generator such as Bluetti, Jackery, ECOFlow, etc use the same port for the PV panel or the AC to DC charger to charge the batteries, I wonder what they have done to accomplish that.
 
A power supply outputs a set voltage,
A solar array does not, the voltage / current will vary somewhat depending on solar radiation as well as load.

Some MPPT controllers will not work properly when they cannot sweep the voltage from vmax down to minimum.

Robin Gudgel , founder of Midnight Solar, has stated on this forum that they test their MPPT controllers using a bench power supply at the factory as a routine procedure.

Some users use a dropping resistor between the fixed voltage power supply and the controller, it’s not something that I would do.

Personally I do not do that as I have far more solar power available than grid power
I have Victron Stecca chargers that can be programmed to charge properly. They are AC/DC and can operate from 85 to 265 volts 45-65 hz and 90-265 volts DC I power these with either my 256 volt dc array (normally used for direct dc hot water) or my Onan NH-3 6.6 kw generator which can be set for 120 volts 60 amps or 120/240 volts split phase or euro 240 volts single phase with the ground at the correct point

Most of my systems are Midnight Solar Classic 150’s or Kid controllers but I do have a Victron 150/35 in a Ford Transit van camper conversion
 
I have explained why the mppt algorithm causes issues for power supplies

The solution is again

1. Current limit the mppt to less then the power supply max , the Victron. Can do this via “ max battery charging current setting “

2. Ensure the power supply current capacity is greater then the mppt max current

3. Get a PSU with constant current ability

4. Insert a power resistor in series with the PSU output.
 
I talked to a technical support man at the supplier of my Victron products, Bay Marine Supply, who told me that it is "not advised" and "not supported" to feed either the Victron MPPT charger or the Victron Orion TR DC-DC charger from a power supply.

Consequently, I will not use the Victron products do so.

I will continue to use my PWM charger to charge my battery from shore power.

Thank you to everybody who reached out to help me.
 
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