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#1
Midnite Combox / Re: Status of the MNS COMBOX P...
Last post by Barry Fields - Today at 10:23:16 AMIn the simplest of terms that an elderly Tennessee Hillbilly can understand:
What is the issue the Combox is intended to resolve?
What is the issue that MQTT is intended to resolve?
I do appreciate y'alls patience.
What is the issue the Combox is intended to resolve?
What is the issue that MQTT is intended to resolve?
I do appreciate y'alls patience.
#2
The Rosie / Re: Grid Sell Update?
Last post by Wizbandit - Today at 07:08:00 AMYesterday I successfully tested the new SELL Code, it worked great but not until I found a big problem...
I have 600Ah of EG4 Lithium batteries on a stack of Rosies, when I tried the first test.app release Rosie would not stay connected to AC IN & sell, kept ramping up and bam, drop AC in. Like most inverters I have setup to sell I want it to sell to the float setting which is 54V which is what the EG4 sheet says to use for float. I blamed Rosie and reverted back to beta.app code to run in grid-support mode for now.
Move up to yesterday, chatting with Ryan and testing it was the Lithium battery's BMS's causing the problem or just the way Lithium batteries work in general. Even though we have to use lead battery settings and terms (yes, Absorb is a lead term) you can make any charge controller charge a lithium battery.
My Barcelona and Hawkes Bay on this dual Rosie system would ramp up to the 56.4v absorb setting and BAM, when it hit the amps/watts would drop to Zero and the charge controllers would ramp back up and repeat. This drop in power also caused the SUnny Island I was using to sell to drop off.
I watched the battery voltage during charging from 70% SOC and once the voltage got to 54v it stopped and no matter how much current was going in it would not move. I had 160A going in and steady at 54v until the SOC got to like 98% then the voltage went up really fast to 56.x and that's when the Charge Controllers would stop pushing current and cause selling issues.
The fix was to set the Absorb time (another lead battery setting) to max which is 6 hrs with battery type Lithium and use ENDAMPS to go to FLOAT. The new MPPT's make good power in FLOAT and don't need to be in BULK to sell like the Classic does (engineering is working on new Classic Lithium code that will fix that). The issue was it seems the BMS's would open to stop charge current at 56v and above and this was the problem.
SO I set ABSORB = 54.5 and FLOAT = 54.1 and Rosie SELL to 54v, ENDAMPS to 10A It seems the EG4 will charge with absorb set to 54.5 and when the current drops to <10 it must be like 90% full which is fine for on grid. Yesterday was a perfect day selling power to the Grid. My RV on L1 of the stack would show only like -500w selling on that leg but -2Kw plus on L2 with Rosie-2 only selling when needed. When not selling Rosie-2 would be in standby. I think I peaked out at like 5Kw to 6Kw selling around 1PM. After a week or so testing with no issues we will move this code to BETA.APP
I have 600Ah of EG4 Lithium batteries on a stack of Rosies, when I tried the first test.app release Rosie would not stay connected to AC IN & sell, kept ramping up and bam, drop AC in. Like most inverters I have setup to sell I want it to sell to the float setting which is 54V which is what the EG4 sheet says to use for float. I blamed Rosie and reverted back to beta.app code to run in grid-support mode for now.
Move up to yesterday, chatting with Ryan and testing it was the Lithium battery's BMS's causing the problem or just the way Lithium batteries work in general. Even though we have to use lead battery settings and terms (yes, Absorb is a lead term) you can make any charge controller charge a lithium battery.
My Barcelona and Hawkes Bay on this dual Rosie system would ramp up to the 56.4v absorb setting and BAM, when it hit the amps/watts would drop to Zero and the charge controllers would ramp back up and repeat. This drop in power also caused the SUnny Island I was using to sell to drop off.
I watched the battery voltage during charging from 70% SOC and once the voltage got to 54v it stopped and no matter how much current was going in it would not move. I had 160A going in and steady at 54v until the SOC got to like 98% then the voltage went up really fast to 56.x and that's when the Charge Controllers would stop pushing current and cause selling issues.
The fix was to set the Absorb time (another lead battery setting) to max which is 6 hrs with battery type Lithium and use ENDAMPS to go to FLOAT. The new MPPT's make good power in FLOAT and don't need to be in BULK to sell like the Classic does (engineering is working on new Classic Lithium code that will fix that). The issue was it seems the BMS's would open to stop charge current at 56v and above and this was the problem.
SO I set ABSORB = 54.5 and FLOAT = 54.1 and Rosie SELL to 54v, ENDAMPS to 10A It seems the EG4 will charge with absorb set to 54.5 and when the current drops to <10 it must be like 90% full which is fine for on grid. Yesterday was a perfect day selling power to the Grid. My RV on L1 of the stack would show only like -500w selling on that leg but -2Kw plus on L2 with Rosie-2 only selling when needed. When not selling Rosie-2 would be in standby. I think I peaked out at like 5Kw to 6Kw selling around 1PM. After a week or so testing with no issues we will move this code to BETA.APP
#3
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by Barry Fields - May 22, 2024, 06:40:44 PMQuote from: boB on May 22, 2024, 04:05:25 PMBarry, let's see your idea of a phone app and how it would show data
Can a person connect to the Classic or Hawkes with a android cellphone? I think yes.
Any data in the BBMT should be available over the modbus/canbus thru the Classic/Hawkes.
#4
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by boB - May 22, 2024, 04:05:25 PMQuote from: Barry Fields on May 22, 2024, 12:38:11 PMPause for reflection:
Is there anything I have suggested that:
1) "could not work"?
2) That would require any modification to existing MidNite charge controllers except maybe a firmware upgrade?
3) That would not add to or improve the capabilities of MidNite charge controllers?
Any positive or negative feedback would be appreciated.
Barry
Barry, let's see your idea of a phone app and how it would show data
That's what people want
#5
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by Barry Fields - May 22, 2024, 12:38:11 PMPause for reflection:
Is there anything I have suggested that:
1) "could not work"?
2) That would require any modification to existing MidNite charge controllers except maybe a firmware upgrade?
3) That would not add to or improve the capabilities of MidNite charge controllers?
Any positive or negative feedback would be appreciated.
Barry
Is there anything I have suggested that:
1) "could not work"?
2) That would require any modification to existing MidNite charge controllers except maybe a firmware upgrade?
3) That would not add to or improve the capabilities of MidNite charge controllers?
Any positive or negative feedback would be appreciated.
Barry
#6
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by ClassicCrazy - May 21, 2024, 11:07:21 PMI have a friend who uses PLC to do things like you have drawn up. It can read modbus and sensors and has built in relays and logic , etc.
I don't know PLC's but have messed around with Node Red a little bit which can do all by running on a Raspberry Pi or PC . There is no end to the coms , inputs , outputs, of any type with Node Red. But I am no expert in that - just know the basics .
Larry
I don't know PLC's but have messed around with Node Red a little bit which can do all by running on a Raspberry Pi or PC . There is no end to the coms , inputs , outputs, of any type with Node Red. But I am no expert in that - just know the basics .
Larry
#7
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by Barry Fields - May 21, 2024, 08:48:06 PMIt is best that I drag this all together in an illustrative format. Most all the proposals have been discussed in detail in a myriad of posts over the last year or so.
I am indeed open to answer any questions?
I want to express my thanks to many of you for your patience and cooperation.
I am indeed open to answer any questions?
I want to express my thanks to many of you for your patience and cooperation.
#8
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by Barry Fields - May 21, 2024, 05:46:11 PMQuote from: boB on May 21, 2024, 03:51:56 PMThey are ARM Cortex-M3 parts from NXP.
Am I correct in that mcu is limited to 8adc channels (4 differential)?
In which case maybe STM32F030 might be better suited with "The 12-bit analog to digital converter has up to 16 external and two internal (temperature sensor, voltage reference measurement) channels and performs conversions in single-shot or scan modes. In scan mode, automatic conversion is performed on a selected group of
analog inputs.
That would allow for 4bank monitoring (uses 8 channels) plus Remote Battery Sensing (1 input).
Quote from: Barry Fields on May 21, 2024, 12:22:34 PMIn general if you wanted an MCU to be able to communicate with either modbus or canbus, can that be done with one bridge and one r485 connector or would you need two?
I am still learning.
#9
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by boB - May 21, 2024, 03:53:26 PMQuote from: Barry Fields on May 21, 2024, 12:22:34 PMMore stuff I do not know:
In the Classic is the battery voltage stored in a registry as a 10bit value?
Could a more accurate 12 bit value be stored and processed?
In general if you wanted an MCU to be able to communicate with either modbus or canbus, can that be done with one bridge and one r485 connector or would you need two?
Most values are stored as 16 bit words.
Not sure of the A/D word size. Either 10 or 12 bits.
boB
#10
New Product Ideas and Discussion / Re: A CLASSIC PRODUCT ADDITION...
Last post by boB - May 21, 2024, 03:51:56 PMQuote from: Barry Fields on May 20, 2024, 02:37:21 PMIs my security clearance high enough to ask what MCU is used in the Hawkesbay and Barcelona ( I presume they are the same)?
They are ARM Cortex-M3 parts from NXP.
boB