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Hi
I'm looking for a MPPT controller to run a resistive load of 48V and 1500W. Which the Smartsolar 150/35 seems perfect for. IF it can run without a battery.
According to Victrons own FAQ page (https://www.victronenergy.com/live/drafts:mppt_faq Q4) it seems like it can be done if I understand it correctly.
But I've also looked at this forum and most seems to say no. Has anyone actually tried it?
Best regards Casper
It is highly undesirable to operate an mppt solar charger under load without a battery connection. Although it has a protection circuit, the result after a short time will be a lot of smoke and damage to the device.
Yes, it should work if the load is purely resistive and static. If the load is more complex, all bets are off.
Hi all,
Does it really work with resistive load? Does anybody have any experience with usage of MPPT 150/70 (or similar) for 24V DC heating element but without battery?
Thanks for sharing experiences in advance ...
Ji
I mistakenly had a RS450/100 connected to a Quattro with no battery. When there was enough sunlight, it ran the load. When a cloud came over it dropped out with a low battery alarm. Based on that I would expect it to run a resistive load quite happily, but it's an assumption.
Cmon folks... Its down to the load...
I expect the MPPT charger will protect itself but when h load esceds the input the voltage will drop, because thysics.
Best case the load shuts down the voltage rises and the load strts up, thid could happen quickly and repeetedly and that is likely not good.
A batery, even a small one, damps this oscillation and the load will cycle on and off at a rate determined by the available solar charge, the battery capacity abd he viltage setpoints.
This may be OK, it depends on the load and the frequency. There are few loads that will tlolerate undervoltage for long even if rgw charge contrller is capable of working in CC mode. Battery chargers are one of the few... Need I say more!
Hi all, is it working with a resistive load? What if I use a Victron 100/20 before the Mppt of a Power station to limit voltage/current. I have got solar for 90vdc open circuit, 75vdc at max power, 11adc at max power. Could I use a Victron 100/20, without battery, connected to the Mppt of the power station? Power station input is 60vdc max, 13adc max, 650wdc max. To hit max power the Victron output could be set to 54vdc, 12adc? Thank you.
@Michele Chiesa Hi all, is it working with a resistive load?
The Victron mppt is a battery charger.
It is not a power supply to feed another mppt (or load).
To do such will result in bad performance, or damaged mppt(s).
