Power

[Vik351]

it would depend on how big the bid is;

A long time ago, there was a bloke on Naru who had a job for life cleaning panels. - not so much now

I like to camp by a river...

bloody Pelicans...!!!

vik...

[Vik351]

So if ya have a few plops of bird poo on your panels,or A single panel, does that panel go dead as I have heard in my sheltered solar life, or is it just where the poo is that ya get that foot print bit of power less...???

or is that just house panels on ones roof at home

vik...???

It would only reduce the amount of energy coming from the panel, just like when a cloud comes over, but constantly until you clean the panel. If you use an mppt controller, they will provide much more energy on a cloudy day, than a pwm controller. Have parked under huge shade trees on really hot days at the same place many times over the years and when previously using a pwm controller got little input, but the mppt, always puts much more energy into the pack.

Down here in Tas, (before lifepo4) used to have trouble having power at night in the middle of winter as the sun is so low and the panels sit flat on the bus roof. When changed to mppt, the problem was much less and since lifepo4, don't even think about it, as we always have enough power.

Ya reckon Terry has heard of a MPPT controller...???

Best I inform him when he does my solar set up...

vik... So MPPT not PWM...!!!

[native pepper]

Ya reckon Terry has heard of a MPPT controller...???

Best I inform him when he does my solar set up...

vik... So MPPT not PWM...!!!

Could be wrong, but you may find Terry is not to keen on mppt as a choice of controller. In my opinion it all depends on how much time on the road you spend. We spent about 9 months of the year travelling round Tas and Aus, in 95% of places we camp, no access to power, so rely upon our bus system.

When on agm/gel, the change to Mppt gave us more energy input over a day under cloudy conditions, compared to pwm. On very sunny days, that may not be the case and it may also depend on how you set up your charge system. With panels flat on the top of the bus, to me, mppt will give you a better input early and late in the day, compared to pwm.

Not being technically minded, can't tell you how it all works, I went for a complicated system of relays etc to BMS, active balancers and more relay switches, to cope with the lead acid controllers. Now have simple single stage lifepo4 charge controllers and cell equalisers, which bulk charges to 14v and switches off. The equaliser keeps the cell line balanced throughout their charge discharge regime, in the last couple of years, haven't needed to touch the system, or even keep a watch over it. It just works and my cells are very happy. Life on the road and at our off grid home, is no different to those connected to the grid when it comes to energy use. We are just more frugal with what we use.

[Vik351]

It just works and my cells are very happy. Life on the road and at our off grid home, is no different to those connected to the grid when it comes to energy use. We are just more frugal with what we use.

Sounds good native pepper, the sort of set up a gumby like me needs, set and forget... I know I will have to learn the ropes to keep an eye on stuff,but the modification days for that sorta stuff aint even gunna begin...!!!

I'm sorta gettin the idea on how it all works, instead of just two 12 volt AGM's hooked up to the panels as in my old set up, the life pro is a whole heap of three volt all hooked up together(cos a whole heap of batteries is better than just two big ones...???) but you have to keep an eye on each one with all the gizmos that do that for ya ,then the all are happy...

Bit like one slack dog in a sled team,the rest have to pull it's weight and end up not happy Fido...!!!

Then it's down to Ford is better than Holden...

I'm safe,I drive a subie...!!!

vik...

[Craig]

I am having trouble getting my head around how a MPPT controller that must use some of the solar input to to activate it can out perform a PWM controller in a low light situation. The PWM would be starting sooner and working longer as all the input power is being used to charge your batteries and not being used to power the controller. Maybe your PWM wasn't set up correctly?

Vik,
don't stress it. If Terry sets your system up it will be set and forget and more than likely a PWM.

Craig

[Vik351]

I am having trouble getting my head around how a MPPT controller that must use some of the solar input to to activate it can out perform a PWM controller in a low light situation. The PWM would be starting sooner and working longer as all the input power is being used to charge your batteries and not being used to power the controller. Maybe your PWM wasn't set up correctly?

Vik,
don't stress it. If Terry sets your system up it will be set and forget and more than likely a PWM.

Craig

Now there's a reassuring tone... thanks Cragelles...

You bin round the block... and to his nest in Mannum from what I can gather...

vik... Yep, all faith in the ladd...

[native pepper]

From my understanding Craig, pwm is just a switch control which provides the batteries with full power input and has an input voltage restriction. Whilst mppt can handle voltages over 100v easily and over the day giver you the maximum energy it can, meaning you can use 24v panels on your 12v system. This means thinner wiring, longer runs and even wiring panels in series.

Mppt are much dearer and they claim have a shorter lifespan because of more electronics, but over a long period will provide a better outcome. Pwm is cheaper but restricted by voltage input and don't believe you can use 24v panels for a 12v system with pwm, but happy to be corrected. There are of course 12/24v pwm controllers, but don't know anything about them.

I go by what I have experienced over the decades. Until mppt came about, it was just pwm and as we have been off grid since the mid 1970's have a good understanding of what has provided us with the best outcome. When switching my house to mppt, from pwm on lead acid, the difference was pretty dramatic. Then we switched to lifepo4 and the outcome was spectacular compared to what we'd put up with over the years. Now with the setup we have, very happy campers and in my mind and from what have been told. Pwm is great for certain applications, but if you want a long term return and balanced charging in all weather conditions, mppt is the way to go.

Like everything, most is personal choice and am pretty sure Terry could explain it much better than I ever could