6000W solar and inverter upgrade!

Its not like either of you did it... Both covers were fine, oddly enough. 

I have to say this is a very nice looking inverter, probably the nicest I've seen thus far! Stainless and shiny!

Finished swapping out the batteries today, but ran into trouble with the Daly Smart BMS. I must be missing a temp sensor or something, as there's a related fault code on the BMS preventing charge/discharge, and the one sensor reads -40C. I'm reaching out to Daly about it but I have my doubts as to whether they'll be responsive... So for now I'm going to charge to 54.4V, and keep an eye on the cells manually while I look for a new BMS.

Today I was able to replace the output terminals:

Getting ready to hook it up!

I did acquire some of the "new connectors" currently being used but decided against using them. They are quite a bit smaller, which is nice, but the current terminals are far beefier than anything I've had on a PJ inverter.

Finally I built some 4/0 cables to hook it all up:

The new 43kWh LFP bank is charged full:

35kWh into the bank, so SoC was around 20% on arrival.

In light of some conversations around 240V charging problems, I've decided to hook up the inverter as I had my PJ inverter- output only to a manual changeover switch, no input/ATS/charge.  ATS/charge were two of my most anticipated features- the cool as heck ones I've been waiting for. Just plug in an the inverter would switch over and charge from shore- sweet!

However,  the lack of a double-pole relay internally to disconnect L2 causes issues with my use case. My use case means I cannot avoid a ground/neutral bond upstream of the input, and I must assume ground is shared between N-input and N-output as I only have one ground available to me, I need a ground connection to chassis, etc. In retrospect I should have given 120V charge a little more consideration (for other reasons, primarily generators) but I do believe 240V input is the way to go for me. 

Every outlet in my bus is GFCI... which recently actually protected me from shock when my 10+ year old fridge developed a ground fault three weeks ago- apparently compressors can develop ground faults when they are near failure. We had a pretty big ordeal replacing it with something brand new from the store...

So... a bit disappointing. What I would like to do is install the inverter as the ATS- running only inverter output to the AC panel and the shore inlet to inverter input, so that I can take advantage of ATS/charge, and later have computer control over ATS/inverter modes. It would also render me immune to problems like open neutral at faulty pedestals. Perhaps I could buy a newer revision board with the double pole relay and retrofit it later... hopefully for the time being I don't have to plugin at all =).

<a contenteditable="false" data-ipshover="" data-ipshover-target="/profile/2-sid-genetry-solar/?do=hovercard" data-mentionid="2" href="/profile/2-sid-genetry-solar/" rel="">@Sid Genetry SolarI got it hooked up, powered on. Fans spin up hiGH then go silent. But as I was playign with the BMS (temp sensor) one of the times the inverter came back on, it came on with a red light + beeeeeeeep. I couldn't see the screen, don't remember if it was blank or what. Turned it off and waited a little while... now I hit the button, it turns green and no activity. Uh oh...

No smell or anything, just silent with a green light. No WiFi board screen.

Oh, it came on again this time after letting it sit a while. Having the BMS cut out power on it like that must have put it into a weird state.

Nope, something is wrong. After a while it has a fast blink red with the beeeeeeep. 

Will PM you.  Sounds a bit like something isn't plugged in.

I will note that the transformer is almost dead silent at idle.  If you're used to the loud buzz of a PJ...it's not going to be there.  But the LCD should be lighting up when you turn the power on.  Fans speeding up fast for a few seconds is normal startup behavior, and would normally indicate the LCD board is working.

Well, thanks to help from  <a contenteditable="false" data-ipshover="" data-ipshover-target="/profile/2-sid-genetry-solar/?do=hovercard" data-mentionid="2" href="/profile/2-sid-genetry-solar/" rel="">@Sid Genetry Solar with the inverter the past couple days, I got it running yesterday. He also resolved the charge/ATS issue for me, so I'll be gearing up to get that all installed here shortly. Since yesterday evening the inverter has been humming away in its new little home:

All looked well:

Shortly after I calibrated it, switched bus power over to the inverter and went to bed. I set it so the fans would stay on low rather than spin up every so often, made it easier to sleep. I wonder if I could get the fan speeds a little lower even for the "fan off" setting.

Today without realizing it I had kicked off a mini stress test when I went about my business and threw a pizza in the oven!

120V Ninja convection oven, pulls around 1800W-2000W.

Remote display is such a cool feature for times like these...

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Solar input jumped with the new load:

And my yield today has been a bit higher after running the AC all night! Looks like I have a solid 6-7 days of standby power for extended overcast with this new battery bank.

Overall super excited to see this all come to fruition. Its been months in the making.

Thank you Genetry Solar!

*munches on solar cooked pizza*

Yesterday I ran the above oven for a little over two hours, no hiccups at all. Knowing virtually nothing about how the fans are programmmed, behavior seems like it could be better- I would see fans spin down when load was high (oven elements switch on/off based on internal oven temp) only to spin back up when temps rose again. Also, when the food was finished cooking the fans continually readjust while the inverter as a whole cools down. I think cooling back down to average temperature should be done more consistent and aggressively, then shut the fans down to their minimums rather then modulate down. Ultimately keeping the inverter cool is the highest priority... its just more "user friendly" if the fans adjust as infrequently and gradually as possible. Just an idea!

Anyway I knew the already warm cabinet would probably not be a great environment for the inverter, so yesterday I installed an exhaust vent in the cabinet. Air at the top of the cabinet is sucked directly outside. 

(image of cabinet with vent fan)

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Now this creates negative air pressure in the cabin, causing air from anywhere it can enter to enter (mostly at the front door), but I think this is a win compared to the alternative of much hotter air in the cabinet leaking out into our hallway. The air blowing out does feel hotter than the summer ambient air outside.

The blower fan is thermostat controlled, so it will throttle itself as needed. Its silent on the highest setting... I have another one of these fans below in the battery compartment.

During winter this vent will be capped and not operate, as will the battery box vent.

It is a fine song and dance, I must admit.  I'm open to viable suggestions and ideas; currently the fan speeds are directly controlled by the measured temperatures (as sort of detailed in the manual).  These temperatures (as you noticed) lag behind the load on the inverter, as does the generated heat.

The constant rise/fall of temperatures can be caused either directly (as a result of the increased fan speed cooling the heatsink) or indirectly (noise in the measurements and/or different thermistors switching control on the fans).  The fans add their own delay to PWM throttle control as well.

If you'd like the fans' minimum speed to be directly determined by the total load on the inverter, you can use the ProCool settings (Proactive Cooling) on the appropriate fan channels.  These will ramp the fans up directly based on the load, regardless of temperature--and if the temperature rises past the "minimum" set by ProCool, the fans will throttle past that.

You can tweak the fan settings, but please make sure you understand what they do before you adjust them.  Sean has reported several problems with customers messing with fan settings they didn't understand, resulting in the inverter overheating...or really weird fan behavior.  (One of those got all the way to me having to spend half an hour on the phone with the customer to reset the default fan settings.)  Unfortunately, this means that we will have to lock the default fan settings (which we will be tweaking a bit) unless the inverter is unlocked.  I don't like to do that, BUT...there's unfortunately a reason that lawn mowers are plastered with warnings saying, "Sharp blades, do not stick your hands under the mower deck."

Please don't lock out the fan settings just because a few people don't know what they are doing. 

Instead maybe setup the inverter so that the curve can be tuned but have a restore to factory fan curve option and possibly code in a fan settings failsafe where a locked inverter (or unlocked for that matter) will automatically detect a critical temp and crank all the fans to 100% and ignore the custom settings in that instance until it either cools back down to a safe temperature or reaches the critical overheat temperature and triggers a shutdown.  If the inverter needs to save itself like this it could advise the customer to restore the fan profile to factory settings.  Another option may be having a handful of fan curves that are based on ambient temperature, inverter load, and transformer temperature.  Having a quiet mode, normal mode, Proactive cooling (as you described above) and possibly a 100°F+ setting where the inverter sees the high ambient temp and more aggressively cranks the fans early.

All that being said I haven't adjusted the fan settings much because I have the inverter in the basement where the sound is pretty well dampened.  I may try out the proactive cooling but so far it hasn't been an issue as of yet where I currently have mine installed.

So the "lock out" would leave the settings intact, just the user would have to go through the warranty-void unlock procedure to access said settings.  I do plan to make the default settings as lot less aggressive, which should help with noise.  Ideally, most customers won't need to touch these settings...I'm not removing them by any means though.  Will try to make it so that inverters in the field that have customized fan settings will remain as such--but newer inverters going out will have the fan settings locked.

The issue with customers changing said settings is that then the inverter doesn't run right...then they end up consuming our time to fix said problem--or say that the inverter is junk, etc., etc.  One customer had the inverter go into overheat shutdown without the fans ever turning on--by setting the fan PWM option to 20Hz (but the GS fans require 20KHz in order to accept a PWM throttle).  Yes, the fans will throttle up to full speed 95%+ PWM...but with the rapid temperature rise by the time the fans finally spun up, the fans couldn't prevent the inverter from surpassing the shutdown threshold.  (Didn't damage it.)  Another turned the "off speed" up, and then couldn't figure out why the fans kept running all the time.

I set off speed to 1% to keep fans from spinning up and shutting off rapidly at night. Kinda like that, but would be nice if I could make this figure a little slower.

Other ideas for fan control.... load offset, temp control. Fan speed (percent) = Math.min(100, thermistor controlled value + (load pct - load offset) * load factor) or some fancy algorithm like one-way "inertia" (fan speed changes instantly going up but very gradually while going down). In all likelyhood just about any "algorithm" suggested, even if it sounds like it makes sense, will not in practice. 😃