Search results

Good advice. For exposed connections, they are great.

Interesting. I know grounding and bonding can sometimes be a bit of a rabbit hole. I had gone with the practical "why bring any potential problems back into the house to run them through system ground."; BUT...I know the mantra "one ground in the system to avoid ground differntial problems" so...

Question #4: Regarding running the ground - I had thought the whole ground array was to be attached to a grounding rod set near the array. No?

So if I used a plug combiner to combine the "2P" part of each array, I could then run 10awg off that back to the house in pvc, and then to a disconenct, and then to 10awg on the inside?

If I parallel them at the array with a combiner (or a plug connector) then 10AWG is OK for each 4s2p bank, yes?

You are 100% right. Got focused on the current and wattage and forgot about the voltage.

Inverter info: Growatt 12kw Inverter - 2x60A 250V MPPT’s (Split phase 120/240) 100A Max Charging Current 7000W max per MPPT If I ran 8S2P, that would be 312 Volts, 19 amps, and about 4640 Watts. That's an idea, but I don't think the 12awg will take that. I broke it up because the array will...

I have questions...:unsure: 1) By "just combine them at the disconnect box" could I just put a ring terminal on each string and put them on the same lug of the disconnect. (Assuming the disconnect is rated for the combined ampacity.) 2) Maybe (assuming I had plenty of 12AWG) might pay to run...

Thanks for the advice (and sanity check). I would consider running 8, but 12 is more "available" at work. I was considering doubling up 12's, but that seemed overly ghetto.

I've reached that point in the project where I'm second guessing everything and running out of money. I could use some help with the thinking part. My ground mount array will be 4640w, 16x290w, Two banks of 4S2P feeding two separate PV inputs on a Growatt 12k. I plan to mount the disconnect...

I opted to go with a Sunmodo Ground mount system. Price was reasonable and seems fairly robust. Plan to install it when the ground thaws

I have a 48v 100ah LiFePO4 battery on a portable setup. I charged it to 100% and then put it in a non-climate controlled shed where temps can occasionally drop to 0C and below. I know not to charge below 0C and I believe I can dicharge down to -20C. My question: any harm in letting the...

I thought it was a bad idea, and had serious doubts about it holding up the load - until I got the two pieces on the wall. Then there was that "Oh...this is gonna work" moment.

and same for batteries

Signature Solar

I had cinder block. It tends to crumble with many fasteners. Red heads would blow it apart I think. I have used those bolts to install server racks. Not my favorite since I'm not super careful and if you wiggle the bit too much in the hole, those won't grab. I've seen other installers use...

That's a thought.

Update: I ended up going with a Growatt 12kw. It's a transformer based low freq inverter. Heavy as hell, but it can take a big surge. Probably overkill. Priced well, but to do again, not sure if I'd go Growatt. I tried to register the unit,and ran into so much trouble just doing that; so...

I ended up attaching two pieces of unistrut to the cinderblock wall with 6 beefy Hilti toggles (it's hollow block). Then I used 1/4-20 bolts to secure the inverter to the unistrut. On the plus side there is room behind for air to circulate. It was a heavy SOB and took some creative rigging to...

Update: Ended up going with a Growatt 12000T DVM-MPV. It is rated for 250VDC Max ocv. I ended up with Q PEAK BLK-G4 290 watt panels that are 39.19 ocv. So...into each PV input (the Growatt has two rated at 7kw each) I plan to run a 4s2p. That would give me 156.76 ocv and when it gets really...

Update: I ended up using busbars, drilling them and using a bolt and nut to hold on the terminals. They are four 48 volt batteries, and 4/0 runs from the busbars to the inverter. Here's a pic of the busbars and the temporary setup used to put some charge into the batteries (they had been...

Update: I had ordered the batteries back in late october of 2021. They arrived in January and I put them in my basement with the breakers turned off (how they had shipped). Thikngs took longer than I thought, and I started getting spooked they were slowly dropping charge. They were turned...

Ended up letting the rack dictate where I put the batteries. I will put some hardware cloth between the batteries (and on top of the inverter) to let the mice know they are not welcome there.

Been following Engineer775 for a while. I looked into Sinclair but it's a bit pricey (steel has gone up a lot and delivery to east cost is almost the same cost as the materials). I don't have the "luxury" of Carolina clay - loads of rock mixed in with my soil - so driving posts is not an...

Ended up using an old small server rack. It was a mistake since it slowed me down a lot getting parts for it (copper bus bars and insulators, and the rack width was not a standard and batteries would not fit in easily - thus the weird spacing) - would have been better off just buying the rack...

It *looks* like everything charged fine. I had a "BMS Communications error" about 15 minutes in on the charging, and the unit stopped charging. Shut off everythign and put everything back on, and it was all good after that. Eggo, thanks for the advice. Made the process MUCH smoother. Got...

Seemed to be communicating fine, then for no reason threw an error code 20 (lossof BMS communication) and stopped charging. This was early in the process. I shut everything down (inverter/ac in at breaker on both sides and the breakers on all the batteries). Then I turned everything back on...

It tracked the battery status, so there's that.

Connected up growatt 12k to four EG4 lifep4 batteries. Set dips, ran data cables, chose lithium in option 5 and in 51 chose L01 (per signature solar). Growatt tells me batteries are at 49% and charging. Can I assume it is talking properly to batteries if it is able to grab this info?

Cool. I have limited time at the site, and would like to be able to "charge them all at once" - I know it doesn;t change the overall time, but I can walk away and not chewck on them for a while and know they are ALL charging up.

It would be a good amount easier to just connect all teh communicaiton cables and then go for it. BUT...I thought they needed to be balanced to start?

True (I try not to think about it - seems like a big waste). I want to try the standby mode - says it needs a 500W load to wake up, and I'm not sure my sump pump will pull that. I have to test. As for charging, I thought I had to top/bottom balance them.

Finally wiring in my Growatt12k to my four paralleled EG4 LIFEPO4's. I have no load on anything yet. To bring the batteries up to charge, my plan was to conenct the BMS cable from the Growatt to ONE of the batteries, set the battery to master, and then charge it with the Growatt. Then power...

busbars were 1/4" and actually tougher to drill through than the cabinet behind them. It was probably thick enough that the threading would have worked. But...drilling a hole and using a bolt went wayy faster.

Ended up just going with stainless short bolts and nylock nuts.