PWM or MPPT.

[Cuppa]

Correct me if I'm wrong @Cuppa but basically the PWM charges are in short regulating on off switches.
They switch on at a set voltage and off at a set voltage.
Not sure if top end PWM chargers can supply a float voltage but my cheaper one doesn't. .

As for pannels, try find them without controllers.
They are usually cheaper..

PWM = Pulse Width Modulation - (https://en.wikipedia.org/wiki/Pulse-width_modulation). Not sure I fully understand it, but basically the 'on/off switches are electronic rather than mechanical (Mosfets) which do what they do constantly at very high speed. Has nothing to do with whether a regulator which uses them has a 'float' capability. This is to do with multi stage charging. However I would think it would be highly unlikely that any regulator which has no float capability was anything other than a 'dumb' charger & almost certainly not going to employ PWM technology, regardless of what it says on the regulator. If a regulator does not have a float capability it would be an ultra cheap one capable of damaging the battery & shortening it's life. They are available for a couple of bucks & are best consigned to the hard rubbish asap. ALL reasonable to top end solar regulators use PWM technology, increasingly more also use MPPT technology to optimise this. Unfortunately the acronyms have been employed by shonky manufacturers & vendors as selling points with little basis or meaning. I would be 99.9% certain that your PWM reg has about as much PWM technology in it as my big toe Kallen.

As far as panels with a regulator attached to the back of the panel, you are correct, they are not a good idea, & very few of those regulators are worth keeping. But if kept, if removed from the panel & installed close to the battery together with heavier cabl, will improve the efficiency/performance of the solar set up. I have bought portable panels with panel mounted regulators, but treated the regs & supplied wiring as throwaway items, & the panels themselves were still good value.


Of the ebay sellers I think that Low Energy developments who have a reputation for quality at low prices.Others, in my experience have low prices & low quality. Problem is that all solar panels look much the same, but looks are deceiving.