MPPT Controllers on E bay

gemmybob · Veteran Member

MPPT Controllers on E bay

Plendo · Guru

Bob, to date I have purchased two MPPT charge controllers from companies through the internet, and I have received a good product in both cases. One was a small (30A) unit I use with my portable panels, and I knew nothing about the company, made my decision totally on the advertised specifications of the device. The second was a large 50A unit that I run on my roof top system charging my 24V storage battery, in this case I was investing decent money, and I researched the company (MPP Solar) thoroughly first.

There are two sides to a solar charger, the input side where it controls the load on the panels to hold them at their optimum voltage, this is the key function and where the MPPT algorithms are used.

Many MPPT chargers then also control the output to the battery to be about 0.5V above the battery voltage, thus maximising the amps they can provide to the battery. They do of course still also respect the programmed maximum charging voltage.

Some of the lower spec chargers use MPPT on the input side, then use a form of buffered PWM on the output side. They are still MPPT chargers, and the loss of efficiency is typically small.

gemmybob · Veteran Member

Thanks for the heads up Plendo, seems do my research and buy reputable to avoid risky business is the way to go.
Cheers
Bobc

03_Troopy · Guru

Bob, the ones that look like this are are generally not MPPT controllers, even though they say they are.

Here's a review MPPT30 Review. There are a lot more reviews of the same controller when you get to the youtube page.

cruisaderhilton · Senior Member

smile smile smile 03 troopy ,I have one like you show in the foto ,Being non tech myself it does seem to work for me but do not know what settings to have it on &it it is still set as when I bought it .I have 2 solar panels on roof of caravan going to the controller they are 1x170 amp 1x 150 amp ,there are 2x 95 amp batteries We do not use much power in the van mostly TV and a few led lights and pump when having shower ect .When at van park use 240v,free camping use gas on the fridge .While I have your attention the tv we have uses 12v-240v ,I tried this morning to use a double cigarette lighter ,plugged it in behind tv and the other lead to a 12v adaptor for my laptop computer ,it kept on blowing fuses 10v .Why do you think that is yours JOHN. confuse confuse confuse confuse confuse

gemmybob · Veteran Member

Thanks 03_Troopy,
Seems solar is a subject that needs to be shared, no one person knows all I think. I am aware I know nothing so your advice is timely and helpful to me. thank you.

Mark Bolton · Veteran Member

I bought a "50A MPPT Solar Panel Battery Regulator Charge Controller 12/24V Auto switch BA" from bigger ant eBay for about 80 bucks and it lasted about 6 months. I am reluctant to go the chineese route again and would prefer one that is a bit better quality. I would prefer something with better monitoring because the charges can be all over the shop. I am using a cheap DVM module that reads .4 volts low. eBay 5 bucks.

I am running 400 Ah 12 volt on 600 watts in winter down south.

Researching now into what I should have bought.

Plendo · Guru

Hi Mark,

have a look at what MPP Solar offer. That is what I am using (1,200w solar into 50A MPPT, charging 200ah of Lithium Battery at 24V). I have found MPP solar nothing but professional and helpful.

Have a look at their web site, then look for their products on ebay if interested.

Jaahn · Guru

Hi smile

Crusaderhilton, if you had a laptop charger it could draw 10amps or more on its own. When first plugged in it may need even more to get started. Then you have the tv drawing a couple of amps. That is why the fuse blows. It is all to do with power drawn out of the socket. You must be aware how much all your items need and see if your socket can supply it.

Mark Bolton, If you buy an item that is only a quarter of the cost of another recognised one, you should be a bit suspicious of the performance. I would think that most of the middle priced units are made in China. Perhaps all even. I used a Tracer and found it OK. I would buy another one again. However there are plenty of overpriced ones of this brand and others available from Aussie suppliers who seem to be into gross overcharging. hmm

As Plendo suggested do your homework !! Another suggestion ! I have always found has served me well, is not to run things at their maximum specs if you want long life. Its a bit like running the engine to the red line all the time and expecting a long life from it. confuse

Jaahn

-- Edited by Jaahn on Thursday 6th of August 2015 10:00:12 PM