Why is mppt better than pwm?

Don B. Cilly said:

Also MOSFETs will not arrow reverse current.
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All do indeed !
Every FET has a built-in protection diode that will feed reverse current into the panel without an extra blocking circuitry.

For low cost you put a N FET on the low side. I'd agonize for a couple days to save a 1/3 cent resistor.

efficientPV said:

For low cost you put a N FET on the low side. I'd agonize for a couple days to save a 1/3 cent resistor.

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No. That were the usual circuit to switch forward currents (to switch a load) not for reverse current protection (to switch a power source).
Electronic switching is a bit more tricky than dumb relays.
The state-of-the-art ideal diode for solar reverse current protection switches high side.

I don't think anyone is going to take an ohm meter to their Midnight or other expensive controller to see if it is real. So, the discussion is about the moderate price stuff. Sure, I'd like to see it on the high side for the things I'd like to do. But I have three different make charge controllers and reverse current protection is on the low side. I looked out my kitchen window one night and the power shed was bathed in blue. An inadvertent connection was made connecting low side panel to battery. I would never say it is absolute, but sensing a low ohm connection from the + panel to the + battery is probably a good indication it is PWM.

I get tired about hearing ideal diode on this board. Its just a switch.

efficientPV said:

I don't think anyone is going to take an ohm meter to their Midnight or other expensive controller to see if it is real.

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What is your opinion of these lighter MPP CCs based on PWM (not the scam ones that have no mpp tracking)?

An insight into the technology now being used may explain the increase in overvoltage issues now being seen by users of these 'lighter' MPP CCs
that seem to parallel the use of simple PWM CCs.