sunset1

Pretty much! how are your fans doing? Mine go 24/7 like jet engines lol. looking at swapping them out for quieter ones. btw, did you top balance your cells?

Hi Coulomb, Thanks for the link. Seems like it can be quite a complex issue. I shall let you know how it goes. Not sure if this is feeable, but can one phsycally adjust the tachometer inside the fan? I did this on my ebike to increase speed, one simply moved the sensor on the wheel further out. Not sure if the fans have a similar setup though.

They are 80mm. I saw the noctua and was very tempted to get them until I saw the delivery fee and delivery time. Ive just bought these https://pclinkshop.co.za/components/cases-fans-leds/chassis-fans/antec-tricool-80mm-ddb-fan/ Hoping they are a bit quieter than the stock ones in the MECER. BTW how come you changed out your growatt fans? Were they a straight swap?

Yes thank you. Getting a grasp on solar and electricity. Only gripe right now is the MECER ivr 1200mppt inverter has both fans going full tilt 24/7 regardless of temp. And they ain't quiet that's for sure. Guess since it's a cheap inverter they cut back on costs such as temp sensor for fans. Am going to swap out the fans for some good silent ones I found on Amazon. In the meantime until they arrive I'm going to attach a resistor to the fans to lower their speed slightly, stepping them down from 12v to 8 v. We barely draw more than 250w and it's butt cold in our kitchen so I doubt those fans need to be on full blast all the time.

TX, sorry i miswrote earlier. The 17v was the reading from the solar panel. The voltage going to the battery however never really goes over 13.9 as of yet. I’ve only had this setup for a few days. we would like to recharge the battery in 3 to 4 hours. I’ve set the discharge levels to 20%, and full charge to 90%

Hi thanks that explains a lot. We have the mecer ivr1200mppt. Has a 55 amp limit on the mppt and 100 max v for dc. With regards to the 400w etc panel and the conversion to 32A at 14V roughly, would the mppt be responsible for the conversion? we have 2.5 mm2 wire apparently goods for 20amps from panel to inverter/ mppt and don’t want to burn our house down. hope this makes sense.

Hi thanks the max charge is 0.5C so guessing 50 amps. For instance would the battery charge faster at 15v and 50amps or 80v at 6 amps?

My brain gets all fuzzy with numbers. I currently have a 12v lifepo4 100ah battery. it’s connects to a 100 watt panel that produces 18 v dc at roughly 5 amps. it seems to take forever to charge my battery. So.. If I connect say a 400w panel that gives 45v dc with 10 amps make a big difference? Is it amps that speed up the charging? I mean will my mppt step down the 45 v from the panel to say 14 for charging the battery then convert the leftover volts into amps? Thus increasing the amps. trying to figure how to best charge the battery quick from solar. The mppt handles 55 amps

Image of the fan

Tue, 22 Jun 2021, 18:34.pdfHi all, so I’ve discovered that the Mecer Ivr1200mppt has its fans going full tilt 24/7 no matter the load. Don’t mind that but it sounds like jet engines in my kitchen. is there anyway it swap the fans out for quieter ones or perhaps install a temp sensor so they only turn on when needed. Right now These things spin even when ice cold. attached are a few pics of the fans and their 3 pin connections.

Good people Is this connection ok? It is connect the inverter negative to the BMS negative. They both have round crips. I've covered the connection with electrical tape. 12v LFP battery to Mecer IVR 1200mppt

2.5mm2 or 2mm2 Doesnt say on the cable but the electrician says it would handle 20 amps.

80% rule it is. Don’t want to start a fire!

But of course!

One of these guys?

From the newbie to hoohoc I thank you for the advice and the new name

hmmm... I thoight it was 100v. manual says Max PV array open circuit voltage = 100v what is the difference between operating and open circuit?

This is the one right now. See attached but I am thinking of swapping it out and doing 2x 450 watt Canadian etc in series which puts me at roughly twelve amps and about 90 dc. the 450 watt panel are roughly 12 amps each and 40 odd dc.

Hi tetra. Thanks very much. In terms of efficiency how much would I be loosing doing roughly 90v? trying to keep costs down hence series and 20 amp cable.

TX but confused. Better to put them in parallel for some days or buy a bench dc charger? I did see on my bms daly that it balances above 3.5 or something

Hi, Newbie here, We have purchased the Mecer ivr 1200mppt. it is recommended quite a low dc and that we put the pvs in parallel. See attached. My question is why would it want such a low dc when the mppt has quite a high range? was liking the idea of having the panels in series, running higher dc , amps low (around 6 amps) and not having to buy 20m of 8 gauge wire. is there something I’m missing here. we have a 100ah 12v lfp battery

Hi tx. what is wrong with slow current?

How so?

Tx. That thirty dollar shipping fee yewww

got this bms from lbsa Any ideas what these values mean? How does it exactly balance the batteries? found little explanation on lbsa website.