Kohler Batteries (10, 15, 20kw) GoodWe 7600 (ES BP) via Electriq bankruptcy 100$/kw CATL

[netpleb]

Power it down, open the lower cabinet, plug in cable, with the correct cable is just a 5 minute affair. Unplug Sierra Hub on top in battery cabinet.
High probability your system will come right up - gonna be operating in no time. good luck @netpleb , I hope it all works out for you !

Success. After using SolarGo to connect to the dongle/inverter and getting it onto my network, I am now mostly able to communicate with the inverter adequately using this python script https://gist.github.com/netpleb/724b9e23dd461310a7d8cf29b3219aec (disclaimer: provided as-is, no warranty, use at your own risk -- see comment on the gist for an example of what it can do), which uses the same underlying library (https://github.com/marcelblijleven/goodwe) that the Home-Assistant Goodwe Integrations use (https://www.home-assistant.io/integrations/goodwe/ or https://github.com/mletenay/home-assistant-goodwe-inverter).

Interestingly, despite the inverter being physically labeled as a 7600A-ES, the python script seems to detect the inverter's firmware as part of the ET family and uses the ET driver (as opposed to the ES) driver to communicate with it. The data returned by the python script using the ET driver seems to correspond to what I see in SolarGo.

Edit: in SolarGo, I was not entirely sure what to put for the battery selection settings, so I went with "default, 50A" and it seems to work. Not sure if that is the right thing to do though.

 

[wavezz2k]

Success. After using SolarGo to connect to the dongle/inverter and getting it onto my network, I am now mostly able to communicate with the inverter ...

Edit: in SolarGo, I was not entirely sure what to put for the battery selection settings, so I went with "default, 50A" and it seems to work. Not sure if that is the right thing to do though.

Glad you are rolling ! That's cool info @netpleb . Batteries selection: many (& myself) are using Oloid LBS102100a with good success. Default 50*3 for 15 kw-hr, or *4 on 20 kw-hr, also reported to work fine.

Thanks & we'll have to look at those scripts 'home-assist' likely can expand the customization...the SolarGo TOU I've been using, has been running perfect "on-grid" without separate disconnect.

 

[RonFulwider]

What firmware are you using to get the Electriq batteries and the Eletriq Bms to communicate with the Goodwe GW7600A
-ES? I have two 20kw Kohler systems up and running, but the Electriq system isn't cooperating. I've tested the com cable, and tried two different new cables, and I bought and tried a second BMS unit. Goodwe updated my firmware, but that didn't help. I think I need an older version of firmware. Not sure why the more expensive an inverter is the less user friendly it is. Thing should work using the battery voltage if necessary

 

[RonFulwider]

Another Question, can you hook up a serial cable to the serial connection and a computer and get any info off the bms? If so how

 

[RonFulwider]

Update, after upgraded firmware, it looks like my TOFU works as expected; however, the backup option still doesn't work -- that is when grid outage, the house goes dark as if there's no battery.

You do have the ES model? And you have the transformer hooked up?

 

[netpleb]

What firmware are you using to get the Electriq batteries and the Eletriq Bms to communicate with the Goodwe GW7600A
-ES? I have two 20kw Kohler systems up and running, but the Electriq system isn't cooperating. I've tested the com cable, and tried two different new cables, and I bought and tried a second BMS unit. Goodwe updated my firmware, but that didn't help. I think I need an older version of firmware. Not sure why the more expensive an inverter is the less user friendly it is. Thing should work using the battery voltage if necessary

Here is all the info I can find regarding firmware on my Goodwe GW7600A-ES (w/ 15kWh battery):
```
# reported from within the SolarGo App
DSP Information 03.335
ARM Information 14.175
BMS Information 201
AFCI Information 01
Communication Module Information 1.2.1.18
```
```
# reported by home-assistant using the goodwe integration and ET (not ES!) driver:
Firmware: 04038-03-S10 / 02041-14-S00
Hardware: AES 97600
```
I am using the goodwe integration in home-assistant (HA) to successfully control my system now. There is a built-in goodwe integration for HA here: https://www.home-assistant.io/integrations/goodwe/ but I have found that it is better to use the more advanced custom component which is available here https://github.com/mletenay/home-assistant-goodwe-inverter. When you install the custom component it will replace the built-in one.

I have not communicated with the BMS directly, but rather only communicated with it indirectly via the inverter itself (i.e. using the SolarGo app or via python with a linux socat tunnel to the serial device).

Before I got the goodwe wifi/lan dongle hooked up, I was able to also talk to the inverter by using the RS485 cable which was originally connected to the Sierra Wireless fx30s device. So removing that device and connecting a linux box (i.e. laptop) that you control into that serial cable (you might need a usb <--> serial adaptor cable if you do not have one) gives you an RS485 connection to the inverter. Then you can use some linux tools like `socat` to bidirectionally forward traffic to/from UDP port 8899 and the serial device.

By mapping the device to the UDP port I was able to escape modbus hell and then just use the aforementioned python libraries which try to communicate with goodwe inverters via UDP. I was anxious to escape the low level modbus stuff because I have no experience whatsoever in that domain.

Once you get it working with python and/or HA directly, then it becomes relatively straight forward to switch the modes of the system. Here are the things I can change on the fly within HA:


Importantly, I was only able to get python/HA to actually change the "operating mode" of the inverter when using the 'ET' driver in the python library. So, despite my system being physically labeled as an 7600A-ES, it seems that the firmware is much closer to, and possibly nearly identical to, that of the ET family.

There is another variable here too: I am not sure whether the thing that finally gave me control was the fact that I switched to having the "official" dongle do the UDP serving rather than my linux `socat` trick or not. Using the official dongle seems to be the only way to use SolarGo to configure the inverter.

I poked around in SolarGo a bit and chose some default battery settings. But for all I know those settings did not need to be changed. So I am not currently convinced that I actually did anything in SolarGo that could not have been done directly using either python and the socat/UDP comms hack above or (in the worst case) by dropping all the way down into the land of modbus/RTU commands.

Now that I can control my system again, I am hesitant to pull the dongle and test the "is the dongle really necessary?" theory, but maybe that should be tried ...

Hope this is helpful!

 

[wavezz2k]

Here is all the info I can find regarding firmware on my Goodwe GW7600A-ES (w/ 15kWh battery):
```
# reported from within the SolarGo App
DSP Information 03.335
ARM Information 14.175
BMS Information 201
AFCI Information 01
Communication Module Information 1.2.1.18
```
```
# reported by home-assistant using the goodwe integration and ET (not ES!) driver:
Firmware: 04038-03-S10 / 02041-14-S00
Hardware: AES 97600
```
I am using the goodwe integration in home-assistant (HA) to successfully control my system now. There is a built-in goodwe integration for HA here: https://www.home-assistant.io/integrations/goodwe/ but I have found that it is better to use the more advanced custom component which is available here https://github.com/mletenay/home-assistant-goodwe-inverter. When you install the custom component it will replace the built-in one.

I have not communicated with the BMS directly, but rather only communicated with it indirectly via the inverter itself (i.e. using the SolarGo app or via python with a linux socat tunnel to the serial device).

Before I got the goodwe wifi/lan dongle hooked up, I was able to also talk to the inverter by using the RS485 cable which was originally connected to the Sierra Wireless fx30s device. So removing that device and connecting a linux box (i.e. laptop) that you control into that serial cable (you might need a usb <--> serial adaptor cable if you do not have one) gives you an RS485 connection to the inverter. Then you can use some linux tools like `socat` to bidirectionally forward traffic to/from UDP port 8899 and the serial device.

By mapping the device to the UDP port I was able to escape modbus hell and then just use the aforementioned python libraries which try to communicate with goodwe inverters via UDP. I was anxious to escape the low level modbus stuff because I have no experience whatsoever in that domain.

Once you get it working with python and/or HA directly, then it becomes relatively straight forward to switch the modes of the system. Here are the things I can change on the fly within HA:
View attachment 328427

Importantly, I was only able to get python/HA to actually change the "operating mode" of the inverter when using the 'ET' driver in the python library. So, despite my system being physically labeled as an 7600A-ES, it seems that the firmware is much closer to, and possibly nearly identical to, that of the ET family.

There is another variable here too: I am not sure whether the thing that finally gave me control was the fact that I switched to having the "official" dongle do the UDP serving rather than my linux `socat` trick or not. Using the official dongle seems to be the only way to use SolarGo to configure the inverter.

I poked around in SolarGo a bit and chose some default battery settings. But for all I know those settings did not need to be changed. So I am not currently convinced that I actually did anything in SolarGo that could not have been done directly using either python and the socat/UDP comms hack above or (in the worst case) by dropping all the way down into the land of modbus/RTU commands.

Now that I can control my system again, I am hesitant to pull the dongle and test the "is the dongle really necessary?" theory, but maybe that should be tried ...

Hope this is helpful!

Wow, that’s cool having another door & access SW into the inverter with controls options, and interesting finding the “ET” driver.
@netpleb , Great post, & impressive. Helpful to see other’s approaches, as there are a lot of setting variables and ops mode permutations possible.

“via python with a linux socat tunnel to the serial device”
You removed Sierra wireless hub , and go direct to inverter using the serial Db9? Is that Where you connected to serial physically, or at inverter?
The goodwe coms has 485 & serial , each 2 wire, plugs in at inverter control board if I understand that plug correctly.

Regards the VooDoo dongle- working recently with a (2nd) 7600ES, it will “go dark” if I pull the dongle to force a hard reboot of dongle when wifi is not cooperating ; all status lights go out on front display, though inverter continues to operate in it’s mode. Sometimes trying to use “wifi reset” button on Inverter as preferred approach - with reasonable success. That button has a short & long press function, with the “short” being 1/2 second, but not 1/10th - if that makes sense, finiky, but working. The 3 sec fully resets, and the WLAN bridge must be re-entered. I find router is easiest updated in SolarGo: settings, communication; to ad WLAN router back in for SEM logging & local router access. Though local router may lose connexn, once restarted, the logs from inverter stores for many hours and refreshes back up to cloud SEM, once it is reconnected.

 

[netpleb]

“via python with a linux socat tunnel to the serial device”
You removed Sierra wireless hub , and go direct to inverter using the serial Db9? Is that Where you connected to serial physically, or at inverter?
The goodwe coms has 485 & serial , each 2 wire, to inverter control board “plug in” if I understand correctly.

Yep, just to the inverter through the serial Db9. I did not touch the other end of the cable (the one connected to the inverter) but merely took the end that was connected to the fx30 and connected it to laptop via a RS485-to-usb cable.

 

[wavezz2k]

@netpleb Really appreciate your insight on direct connection, gives nice on-ramp for another coms approach.

My experience, SolarGo 15mb manual has 200 pg's info not related at all to 7600 and there's couple difference between the two apps (SolarGo / PVmaster) , but each have a pretty small set settings for the primary operating modes - TOU / Economic, Self-use, Backup, Off-Grid.

An associate wants to setup 'Net Zero' on their property, grid tie. I believe 'Net Zero' can be done, with Self use, Backup or TOU modes by setting export power to zero. Has anyone checked out this approach?

SolarGo, PV Master and operation modes 'Note' >
This is to keep it straight myself, as also to provide road map for other new users, rather than clicking around GoodWe app for hours.
I'm using a TOU this past week, which works well. However, next up, working on a strictly "off-grid" configuration & 'net zero, on-grid' setup. Hoping to get a lingering issue sorted out for a non-grid property's well pump to get a power system running there again..

Some folks state they're having better luck with the older app PVmaster, argument being most case (unless upgraded) it's few years old firmware . My experience, both similar but at times PVmaster will connect locally better (direct to inverter). IMHO, these dongles are absurdly finiky, and have tested a handful - have yet to get one stay "up" properly more than few days at a time.

PDF below,
Sort of “Quickstart to Software Modes Inverter controls” (after wiring & coms are up)

 

[wavezz2k]

@KRZ4U
Backup function-

Barn rat kitty is sitting beside portable EVcharger, connecting into backup lugs on 7600es (via 14-50 typical RV plug).

We restarted the inverter several times (power down, power up), using TOU mode, and ‘off grid’, without having Grid “up”.
Breaker for grid input on inverter is open.

Been running the “grid off” tests for about 3 -4 cycles , on and back off ; so far the backup function is working as should on this 7600es. Prior BP test also seemed good keeping backup lugs powered on.

Gonna take down this inverter- reinstall to ‘no grid’ location tomorrow, where it’s badly needed for water system. Counting on that backup function- big time.

 

[Victorg93308]

@KRZ4U
Backup function-

Barn rat kitty is sitting beside portable EVcharger, connecting into backup lugs on 7600es (via 14-50 typical RV plug).

We restarted the inverter several times (power down, power up), using TOU mode, and ‘off grid’, without having Grid “up”.
Breaker for grid input on inverter is open.

Been running the “grid off” tests for about 3 -4 cycles , on and back off ; so far the backup function is working as should on this 7600es. Prior BP test also seemed good keeping backup lugs powered on.

Gonna take down this inverter- reinstall to ‘no grid’ location tomorrow, where it’s badly needed for water system. Counting on that backup function- big time.

Very nice. These systems are a god send for a lot of us tinkerers. I just got another two systems delivered on monday. You cannot beat the price of being able to put these on shipping containers, adding some panels and you got yourself a nice little setup. I will be installing them soon and will be posting pics. I want to thank all you guys who have been doing all the grunt work on the dongles and everything else needed to make them work out the box.

 

[wavezz2k]

Here’s couple recent confirmed firmware picts. My BP and ES have same firmware, and work with no changes & set to TOU, right out of box. Couple folks have upgraded firmware, with one user (Adrian) saying they then had issue with PV no longer feeding correctly on full battery & subsequently reverted back to earlier “out of the box” firmware.

The iOS SolarGo application on Params page reports firmware number, differently, than “about” detail firmware report. Kinda bizarre & don’t have that figured out.
My systems have .188 and .355 , and seem to work well (on & off grid, now) using kohler bms & batteries & sierra box unplugged. Doing more tests of my off-grid yesterday & today . That one system had a difficult gremlin & best guess was a com cable, or ATX thermal sensor 2-wire.

@RonFulwider Did you get the Electriq BMS part number to talk with a 7600es, or is the EP BMS and battery a “no go” with the plain GoodWe 7600?. You had asked what are firmware revs, they are posted here, all mine from the box are identical. Kohler to a Kohler stack looks good from my tests, bms talks to GW7600 , & have a few weeks of cycles, and couple larger drawdown to (my limit set) of 25% SOC, DOD 75%, and day to recharge. Kohler battery supplemented a evCharge cycle overnight recently as a higher stress test. Backup lugs, power, is up grid off, as should be. Can bring up from cold, off grid, using solar and battery (both aprox 100v). Have had direct 1/2 doz msgs other’s have theirs operating as well.

 

[Mr.Sunshine]

Are these solar kits still avavalable? Have ya'll worked out the issues?
Thank you.

 

[wavezz2k]

Are these solar kits still avavalable? Have ya'll worked out the issues?
Thank you.

Check eBay & local craigslist, there are several sellers. I have 3 different sets been up & running, 3rd is being relocated after it was good in test. My offgrid gave me heartburn , but seem have nailed issue being a bad temp sensor in ATX box, or perhaps wire not connected well. Now back up & running .. There are a few things to watch for, if you plow through the thread, you’ll have a high probability of success. No guarantee in life, except death and taxed to death.. . Edit above is a TOU plot of past 24 hr on grid connect, works as it should. Pretty sweet hardware, price point remarkable. Dongles are PITA, painful to get connecting right- but doable. Better connexn approach is direct serial with home automation and github driver, if you’re tech savy, and inclined. Dongle can be made to work, but can take 5-10 connect attempts, couple reboots, plus sailor language.

 

[Mr.Sunshine]

How I found this thread was research on the Kohler battery system that is being sold on Sun Hub and Ebay. The kits I saw were complete, and ununused. The price was great compared to current kits. I think this could be an option to capture excess solar that my current system produces. I did read through the posts and found a lot of great information. I am not too tech savy, but enjoy the challagnes of keeping tech out of the e-waste scrap pile. Has Goowe offered support and warranty for the inverters that are sold through other vendors? Can one get the dongles needed? Has anyone expanded the batteries beyond the 20kwh kits? I appreciate the info.

 

[milfordtrout]

How I found this thread was research on the Kohler battery system that is being sold on Sun Hub and Ebay. The kits I saw were complete, and ununused. The price was great compared to current kits. I think this could be an option to capture excess solar that my current system produces. I did read through the posts and found a lot of great information. I am not too tech savy, but enjoy the challagnes of keeping tech out of the e-waste scrap pile. Has Goowe offered support and warranty for the inverters that are sold through other vendors? Can one get the dongles needed? Has anyone expanded the batteries beyond the 20kwh kits? I appreciate the info.

This thread is the best support you'll find; broken Goodwe hardware is not going to be the issue--they are high quality with a good deal of protections, the main chore as @wavezz2k says is getting the comms right and ironing out the wrinkles. I know of dongles forsale on Ebay and in Germany--a shop that comes up via GPT; someone may be selling them on this thread. In theory one could parallel out beyond 20kwh systems, but why do that when you can just add another inverter and BMS?

 

[wavezz2k]

This thread is the best support you'll find; broken ... could parallel out beyond 20kwh systems, but why do that .. just add another inverter and BMS?

WIFI DONGLE US SOURCE - JohnT on SFBay Craigslist, 4yourBusiness (Than) on eBay, compuHans (DM, here DIYsolar)
Agree w/ milford, gang more 20kw-hr is way more work than marry another inverter. Frolich guy was using GW7600 output to generator "in" on existing Solark setup as a range extender - an interesting idea.

 

[FrolichInstitute]

I'm currently re-wiring 3 of the batteries into a single 48V, 75A cell to add capacity to my 48V battery bank. Using a JK 24cell, 200A BMS and feeding its wires thru the COM port of the battery boxes. If this works I have 45 more to combine.

 

[wavezz2k]

Good luck @FrolichInstitute . Be sure & catch the note of bypass the breaker in configuration if using a BMS spans across boxes- note by Hodges in the DIY battery build thread (FETguy) . I’m hoping Fet gets master BMS board resistor voltage divider modification working- save lots of wiring & keep all original coms, and power amphenol mates for batteries.. need just add couple 3-way screw lugs for parallel connects.

Completing dongle model saga, @SHADOW54 , - sent to me older 2022 “Wi-Fi Box” dongles to test. Thanks.
I sent back latest new WiFi Lan- for him to compare.

Cliff notes -> these three models all seem about equal, with a possible quicker connect time for the gen 1 "WiFi Box".

On the latest Wi-Fi + Lan, we poked around using PC and normal RJ 45 ( & try next crossover cable), in attempt to see traffic, but have not yet had success using direct Ethernet connection to bypass Wi-Fi. Similar to the home automation and github driver using the DB 9 serial port , a direct would likely provide better coms stability, fewer dropouts and required reboots. I've not seen bluetooth on any these three options, WiFi Box, Later WiFi dongle, nor WiFi + LAN.

Findings: these earlier dongle 'WiFi Box' have “ less “, both hardware and software. The hardware package is minimalistic .. & fairly certain its firmware is smaller code than later generation. .. maybe less is more.
The “ Wi-Fi boxes”, GoodWe named, no joking, came with nice quality OEM 5pin ribbon cable. In a couple short connexn tests on 7600ES on-grid, it connects WiFi tad more quickly direct to the SSID SerialNumber dongle address. Using SolarGo latest iOS App, under the settings 'communication' tab setup, the WLAN bridge setup works same as later dongles, and connects via local router - identical as prior. I don’t yet see an advantage to later dongles models; but have not found source to buy these earlier ones, either.
I’d hoped to see fully generic WiFi internals, but no luck there. Chipsets a standard hardware/firmware gizmo - maybe sourceable..
https://docs.gizwits.com/en-us/module_source/HF/HF-LPB100.html

( EU top solar info, in case anyone looking has no luck stateside. )

 

[wavezz2k]

User Shadow, recently "added on " 35kw Tesla packs to Kohler-GoodWe 20kw-h system setup. Crazy impressive. Hoping he posts info after detail works out. Guessing that's roughly 55 kw-h total pack, ~85% useable for long term cycles. With high round trip efficiencies, using TOU game against very high Calif PGNE rate, that works out for quick return on investment. Especially if the initial system costs are low, like these Kohler-GoodWe sets from auction.

 

[RonFulwider]

 

[RonFulwider]

So with 4 batteries I get a nice clean gradual even discharge. I go to 6 batteries and it drains the first four, leaving the last two untrained. Yes I have a kohler bms
Yes I have the communication cable and extensions. Yes I've swapped batteries and communication cables swapping batteries gets different drain time but essentially goes from 30% usage to 0 and o to 30% charge to 100%.. Are some of the bms only programmed for 4 batteries? My first system works perfect on 8 batteries, the next 3 systems have been answered problem. These are in series.

 

[wavezz2k]

So with 4 batteries I get a nice clean gradual even discharge. .. These are in series.

"the next 3 systems have been answered problem. These are in series." Not sure what that means, hmm. 3 systems w/ 15kw, do not charge discharge correctly? Do You have multiple Kohler battery cabinets chained in series, a la' , 3S 150v?
Do you have spare BMS you can swap? - sounds like behavior repeats with battery & com cable reconfiguration tests, but do not see that you swapped the problem system's BMS . Can you "swap in" that known good 8 (20kw) battery BMS setup into your 6 (15kw) battery stack, and then see the charge / discharge - is that the same or no? If behavior changes with BMS, that would make 'BMS of 6' pack suspect. I'm currently swapping BMS, & stacks around, different configurations as on going tests - & using EVcharger to pull down controlled load - both an ongrid, and an offgrid 7600ES. At moment ongrid is 10kw setups, and offgrid is 15kw,. Previously, the offgrid had a problem with the side 5kw cabinet getting unbalanced (discharged, but did not charge) & had a weird failure to startup , which just got up running correct again (secondly, 4 days ago, remarried up side 5kw cabinet to 15kw). I'm watching this offgrid 7600ES system closely for unbalance to re-occur, plan to make it 20kw within the week.

 

[RonFulwider]

"the next 3 systems have been answered problem. These are in series." Not sure what that means, hmm. 3 systems w/ 15kw, do not charge discharge correctly? Do You have multiple Kohler battery cabinets chained in series, a la' , 3S 150v?
Do you have spare BMS you can swap? - sounds like behavior repeats with battery & com cable reconfiguration tests, but do not see that you swapped the problem system's BMS . Can you "swap in" that known good 8 (20kw) battery BMS setup into your 6 (15kw) battery stack, and then see the charge / discharge - is that the same or no? If behavior changes with BMS, that would make 'BMS of 6' pack suspect. I'm currently swapping BMS, & stacks around, different configurations as on going tests - & using EVcharger to pull down controlled load - both an ongrid, and an offgrid 7600ES. At moment ongrid is 10kw setups, and offgrid is 15kw,. Previously, the offgrid had a problem with the side 5kw cabinet getting unbalanced (discharged, but did not charge) & had a weird failure to startup , which just got up running correct again (secondly, 4 days ago, remarried up side 5kw cabinet to 15kw). I'm watching this offgrid 7600ES system closely for unbalance to re-occur, plan to make it 20kw within the week.

Yes I have 4 7600es systems with kohler cabinets and 8 batteries for each inverter, so 4 20 kw systems. 1st one works perfect and I'm not using it for testing, it runs most of my house so I'm leaving it alone. I'm off grid on all units. Suspected a balancing problem. Have swapped bms units, actually bought extra, have swapped batteries and communication cables. Just bought a capacity tester so I'm testing the output of each battery but this takes like 10 hours a battery. If they test out I will charge all 6 batteries to exactly the same voltage and see what happens. Sound like you had same issue when you went from 4 to 6 batteries, except mine don't discharge
Have 23V in main box and 26.5V in side box when system shuts down

 

[RonFulwider]

"the next 3 systems have been answered problem. These are in series." Not sure what that means, hmm. 3 systems w/ 15kw, do not charge discharge correctly? Do You have multiple Kohler battery cabinets chained in series, a la' , 3S 150v?
Do you have spare BMS you can swap? - sounds like behavior repeats with battery & com cable reconfiguration tests, but do not see that you swapped the problem system's BMS . Can you "swap in" that known good 8 (20kw) battery BMS setup into your 6 (15kw) battery stack, and then see the charge / discharge - is that the same or no? If behavior changes with BMS, that would make 'BMS of 6' pack suspect. I'm currently swapping BMS, & stacks around, different configurations as on going tests - & using EVcharger to pull down controlled load - both an ongrid, and an offgrid 7600ES. At moment ongrid is 10kw setups, and offgrid is 15kw,. Previously, the offgrid had a problem with the side 5kw cabinet getting unbalanced (discharged, but did not charge) & had a weird failure to startup , which just got up running correct again (secondly, 4 days ago, remarried up side 5kw cabinet to 15kw). I'm watching this offgrid 7600ES system closely for unbalance to re-occur, plan to make it 20kw within the week.