PART 2:Connecting a 24v Battery Bank to a 12v 1200w Power Jack GT Inverter

[pro311031]

12v computer fans that can run as long as the inverter is running

[pro311031]

get some 12v fan to keep your inverters cool, on each inverter, and shorten your cables

[MINIMAKERSHEAD]

1200 watts is its peek power

[built2bfree]

Its like the old cheap car amps vs. old Punch car amps theory a better product makes more power.

[pro311031]

what is your current reading?

[SquirrelFromGradLife]

24 volt in a 12 volt inverter? it might say up to 28 volt but you will merely turn electricity into heat that the inverter have to dissipate..you're ruining both the inverter and your batteries. Put two batteries in series to get your 12 volt and then run those in parallel increasing your amps. You want high amps when using an inverter not high volts.

[rboos]

Do the batteries have a discharge rate? Maybe they give a initial peak and then stall at a low discharge rate? I noticed those GT have a small fan to exit the air, but no air entrance? Many ppl install them with the fan upwards, heat tends to go up... My bet is the batteries are not keeping up with the energy drain... or indeed heat is keeping you from obtaining the output you want... BTW 24v is excelent for the 14-28v input. I have the same GTI but in the 28v-55v, operating with 40v in.

[BullittMcQueen1]

Have you tried connecting the grid-tie inverter from your solar panels to the home electrical plug? How does that work?

[Alchaeon1]

....I bet the other 600W is heat - you seem to be runnign at 50% efficiency

[bigjon1359]

I have the same inverter and found out that the ground lug was not a good ground. I put the ground from my 120 ele box right to one of the screws that hold the end plate on and over doubled my output. I was getting 400+ watts directly from 3 - 200 watt panels on a partly cloudy day after changing the ground.

[geocha1962]

I had a small explosion inside the powerjack it burned out several power mosfet's

If your is still ok I recommend to glue some extra heatsink's on the side where the flat surface is in between the fins and an external fan

Good luck

[solarwannabe]

Maybe a clue for you??!! I have the 600W 22V-60V Grid Ties with the Purple Lables, "Sun" I think...... with 2 fully charged 12V batt's in series, or 24V, I could only get around 200-225 Watts off of them........just for the heck of it, and because the DC Voltage range allows on these inverters, I hooked a third 12V, in series, to make it 36Volts. Now I'm it's easily generating 525-550Watts until the battery starts draining. Regards to heat....units going in heat protection, use a fan for that

[Alastor1978]

Power Jack inverter could blow up lol don't buy Chinese grid tie inverters :)

[marzero0]

Maybe its cos the battery system. This inverters with MPPT algorithm puts a voltage to the INPUT and then youve got a current, I dont know how does it work with batteries, but i suppose it have a max limit current to give to the inverter. Sorry for my bad inglish.

[geocha1962]

Quick update

Today I left my to run for a few hours and it did axactly the same thing

And as the time went by the capacity was droping and ended doing around 500W I think that the more it heat up the less time it runs

I wish I had seen your video b4 I ordered my :(

[geocha1962]

My did go up to 980W

It was drawing almost 60 Amps from my battery bank and my wiring started to overheat.

Make sure you don't have other inverters connected to the same circuit

[KusuriRX]

the 1200 watt should as i recall be the total peak wattage. if you check the manual it should tell you what the sustained wattage range is. It may be overheating, does it feel hot to the touch?

[nrodge1]

Well, at least you have a 600W inverter. If I was you I would take it to at least 27V before returning it, just to be sure, you will still be within spec. If you are returning it that is, otherwise just use it for what it will give you I guess. Just remember you will need a actual 800W (not the retail listing, the actual output) from your panels to get that 600W out.

[dalamar437]

I'll see what i can do if I get some time. I only have 2 12v 85w panels. So in full sun I only put about 100w into the inverter. It never gets too hot at the 100w in fact the little fan inside never even turns on.

[nrodge1]

It's intended for 12V solar panels. Which go to 20V open. Try it with your panels and see how it goes first since you probably won't have 1200W of panels right away anyway. And it does have a temp sensor inside and it will shut down if it gets too hot, check for obstructions inside maybe? Open vent holes a little bit more? 600W you would think it could handle without getting overheated. Give us a look inside maybe?

[nrodge1]

But you didn't get 1200W yet, 600W is only 25A and the GTI is 78% so really 800W in is what you would need on th input for 600W out (sorry) so 33A. And those breakers are for DC? Most like that are AC so don't depend on that to give you a amp reading. But you did confirm that if it's 24V in then your wire size isn't an issue but 24V is possibly too low for full output, like right now my 300W is at full out and the input is at 26V, so maybe put two car chargers on them? Or connect your solar!

[dalamar437]

@nrodge1 Yeah I'm using 8 gauge wire so I think that's okay. Hmm yes these are probably AC breakers, any recommendations where I can find some DC breakers? So technically this inverter is intended for a 12v system even though it's range is 14 - 28v. I'm scared to put anything more than 24 in it so I don't damage it. Sounds like I need to find a way to keep it cool too. I still would have thought if it's not operating at full capacity that it wouldn't get so hot.

[islaguy100]

shutting down is a sign your inverter can't take the constant power. you will probably blow out sometime soon. it would last longer if you can find a way to keep it cooler like putting some spacers between the inverter and the board for more air flow. you can even get another small computer fan and attach it to the inverter housing to force air over the cooling channels.

[nrodge1]

Show the voltage at the GTI input terminals and I want my 4 minutes back :) The 300W GTI will put out 240 to 250W with 24V, so if it's about the same ratio then the 1200W one should be near 1000W, but you are assuming a lot without measuring things, it would also be nice to know the input current but you would need to use a shunt, most meters won't go above 10A and you would be in the 45A range. These GTIs are about 78% efficient so expect that. Visit the forums at techluck.com for more circuits